Species Richness Index Research Articles

Composition of the sputum bacterial microbiome of patients with different pathomorphological forms of non-small-cell lung cancer.

Recent studies have shown that the bacterial microbiome of the respiratory tract influences the development of lung cancer. Changes in the composition of the microbiome are observed in patients with chronic inflammatory processes. Such microbiome changes may include the occurrence of bacteria that cause oxidative stress and that are capable of causing genome damage in the cells of the host organism directly and indirectly. To date, the composition of the respiratory microbiome in patients with various histological variants of lung cancer has not been studied. In the present study, we determined the taxonomic composition of the sputum microbiome of 52 patients with squamous cell carcinoma of the lung, 52 patients with lung adenocarcinoma and 52 healthy control donors, using next-generation sequencing (NGS) on the V3-V4 region of the bacterial gene encoding 16S rRNA. The sputum microbiomes of patients with different histological types of lung cancer and controls did not show significant differences in terms of the species richness index (Shannon); however, the patients differed from the controls in terms of evenness index (Pielou). The structures of bacterial communities (beta diversity) in the adenocarcinoma and squamous cell carcinoma groups were also similar; however, when analyzed according to the matrix constructed by the Bray-Curtis method, there were differences between patients with squamous cell carcinoma and healthy subjects, but not between those with adenocarcinoma and controls. Using the LEFse method it was possible to identify an increase in the content of Bacillota (Streptococcus and Bacillus) and Actinomycetota (Rothia) in the sputum of patients with squamous cell carcinoma when compared with samples from patients with adenocarcinoma. There were no differences in the content of bacteria between the samples of patients with adenocarcinoma and the control ones. The content of representatives of the genera Streptococcus, Bacillus, Peptostreptococcus (phylum Bacillota), Prevotella, Macellibacteroides (phylum Bacteroidota), Rothia (phylum Actinomycetota) and Actinobacillus (phylum Pseudomonadota) was increased in the microbiome of sputum samples from patients with squamous cell carcinoma, compared with the control. Thus, the sputum bacterial microbiome of patients with different histological types of non-small-cell lung cancer has significant differences. Further research should be devoted to the search for microbiome biomarkers of lung cancer at the level of bacterial species using whole-genome sequencing.

Species Diversity and Crop Stage in Relation to Predatory Potential of Spiders on Rice Brown Plant Hopper <i>Nilaparvata lugens</i> (Stal)

This study investigated the spider diversity, species, and predatory efficiency of various spider species predating on the rice brown plant hopper Nilaparvata lugens (Stål). The experimental period was divided into three phenological stages viz., active tillering, panicle bearing-grain filling and grain maturity. Diversity indices such as Shannon-Wiener diversity index, Simpson diversity indices, species richness and species evenness index were calculated. Twelve predatory spider species from nine families were recorded and their population was observed to increased with growth stages. Adjusted mortality rates were calculated and predatory potential was observed to follow the order as Plexippus paykulli ˃Pardosa pseudoannulata ˃Oxyopes hindostanicus˃ Neoscona theisi ˃ Thomisius ˃Atypena formosona ˃Tetragnatha nitens ˃ Bianor angulosus ˃ Araneus sp. ˃ Clubiona sp. ˃ Theridion sp.˃ Ostearius melanopygius.

Yak and Tibetan sheep dung increase the proportional biomass of grasses and alleviate soil nitrogen limitation in degraded Tibetan alpine grassland

The dung of Tibetan livestock serves as a natural fertilizer that plays a crucial role in maintaining plant productivity and restoration of degraded alpine grasslands. However, research on how livestock dung affects vegetation composition and soil quality in Tibetan alpine grassland on the time scale remains uncertain. We established three types of nutrients (yak dung, Tibetan sheep dung and urea) and control on a Tibetan alpine grassland in 2017, and measured the vegetation (species composition, aboveground biomass, composition of functional group biomass, and species diversity) and soil characteristics (soil organic carbon (SOC), total nitrogen (TN) and total phosphorus (TP)), and calculated the SOC/TN, SOC/TP and TN/TP ratios) at the end of August 2017, 2018, and 2019. The study aimed to compare the effect organic fertilizers (two Tibetan livestock dungs) and inorganic nitrogen fertilizer (urea) on vegetation characteristics and soil chemical properties, and to assess whether the livestock dung can improve soil nutrient availability level in degraded Tibetan alpine grassland. Our results showed that: (1) Tibetan sheep dung delayed the increase of aboveground biomass, and urea increased the aboveground biomass in 2017 and 2018; (2) yak and Tibetan sheep dungs and urea increased proportional biomass of aboveground grasses and plant species richness index in the three years; and (3) livestock dungs increased SOC, TN, the ratios of SOC/TP and TN/TP in 2018. Our study implies that yak and Tibetan sheep dung stimulated plant growth and altered soil nutrients, while alleviating soil nitrogen limitation in degraded alpine grasslands. The return of livestock dung to soil may be a sustainable alternative to chemical fertilizers in near-natural recovery of degraded Tibetan alpine grasslands.

Nutrient enrichment decreased the Cross-Taxon congruence across bacteria, fungi, and zoobenthos in sediment

Eutrophication is a major problem currently affecting sediment biodiversity in different kingdoms. Surveys at different spatial scales have suggested that nutrient enrichment drove the congruence in biodiversity across different kingdoms. In this study, we examined the diversity indexes of bacteria, fungi, and zoobenthos in Dongting Lake, which is undergoing different trophic levels. The species richness and Shannon index of bacteria, fungi, and zoobenthos were all consistent with the intermediate disturbance hypothesis along the content of TN and TP, with the hysteresis of fungal group. Significant cross-taxon congruence was found in species richness between bacteria and zoobenthos, and Shannon index between bacteria and fungi. Also, the strength of congruence in biodiversity among bacteria, fungi and zoobenthos would decrease along nutrient enrichment. Multi- and single-kingdom networks found that bacterial group contained more nodes and edges compared to fungal and zoobenthos groups, and bacterial removal led to the lowest natural connectivity. And highest positive interaction proportion and lowest absolute value of natural connectivity slope were observed in zoobenthos group. These results highlighted the importance of bacteria as stabilizer in sediment ecosystem, and the most sensitive feature of zoobenthos to nutrient enrichment. Taken together, our results confirmed the cross-taxon congruence between multi-kingdoms, and the effectiveness of bacteria as a potential bioindicator of ecological change.

Diversity of Grasshopper (Hexapoda: Orthoptera) in the Conservation Area of Kerandangan Natur Park, Senggigi, West Lombok

The Kerandangan TWA conservation area has high biodiversity, but much of it is unknown, including grasshoppers. This research aims to analyze the diversity of grasshoppers in the area. Grasshopper samples were collected on two transects determined purposively. This collection was carried out over two months, namely October to November 2022. Data on species and numbers were analyzed descriptively. This analysis includes abundance, richness index, diversity index, and species evenness index. Our findings show that there are 8 species of grasshoppers from the families Acrididae, Pyrgomorphidae, Catantopidae, and Tettigoniidae. The most abundant species was Stenocatantops splendens, whose proportion was 66.67%. The species richness, diversity, and evenness indexes were 2.06, 1.27, and 0.61, respectively. This shows that grasshopper biodiversity in Kerandangan TWA is relatively low. However, it must be conserved because of its essential role in maintaining regional ecological processes.

Diversity of Water Insects in Colo Dam, Sukoharjo Regency

Aquatic insects are among the most successful groups of macroinvertebrates in freshwater habitats. This condition is indicated by the composition, presence and wide distribution as well as the ability of insects to adapt to various types of freshwater habitats which are components of bottom water communities. The aim of this research was to determine the diversity index, species richness index and dominance index of aquatic insects in Colo Dam, Nguter District, Sukoharjo Regency. This research method is quantitative descriptive. Quantitative analysis includes measuring the Diversity Index (H'), Species Richness Index (R1) and Dominance Index (D). The results of research on water insects at Colo Dam found 27 species. The highest number of individuals is the Water Strider with 75 species, while the fewest species are Rhinocypha perforata with 16 species. The conclusion of this research is that the Diversity Index of 3.23 is considered moderate. The type of Wealth Index obtained at 3.67 is considered medium and the Dominance Index at 0.0416 is considered low. Recommendations for further research include adding a Biotic Index to see the quality of the waters in the Colo Dam. It is hoped that the results of this research can become a reference or further research.

Infectious Keratitis: Characterization of Microbial Diversity through Species Richness and Shannon Diversity Index.

Purpose: To characterize microbial keratitis diversity utilizing species richness and Shannon Diversity Index. Methods: Corneal impression membrane was used to collect samples. All swabs were processed and analyzed by Biolab Laboratory (level V-SSN Excellence: ISO 9001:2015), Biolab Srl (Ascoli Piceno, Italy). DNA extraction, library preparation, and sequencing were performed in all samples. After sequencing, low-quality and polyclonal sequences were filtered out by the Ion software. At this point, we employed Kraken2 for microbial community analysis in keratitis samples. Nuclease-free water and all the reagents included in the experiment were used as a negative control. The primary outcome was the reduction in bacterial DNA (microbial load) at T1, expressed as a percentage of the baseline value (T0). Richness and Shannon alpha diversity metrics, along with Bray-Curtis beta diversity values, were calculated using the phyloseq package in R. Principal coordinate analysis was also conducted to interpret these metrics. Results: 19 samples were included in the study. The results exhibited a motley species richness, with the highest recorded value surpassing 800 species. Most of the samples displayed richness values ranging broadly from under 200 to around 600, indicating considerable variability in species count among the keratitis samples. Conclusions: A significant presence of both typical and atypical bacterial phyla in keratitis infections, underlining the complexity of the disease's microbial etiology.

Microenvironment created by Plantago lagopus L. may affect cover and diversity of coexisting species in urban vegetation

Some plant species may exhibit new microenvironments which lead to significant changes in the cover and diversity of the coexisting species. In this investigation, we evaluated the effects of Plantago lagopus L. on the cover and diversity of the associated plant species in the urban vegetation. A total of 70 plots were conducted in sites with- and without this species in urban gardens. Cover of the associated species and different diversity indices including species richness, Shannon-Wiener, evenness, and Simpson indices were measured. The allelopathic potential of P. lagopus was verified using its rhizosphere and non-rhizosphere soils on two target species existing within the same environment. Some soil criteria and seed sizes of the associated species were also determined. Most of the coexisting weeds were reduced in terms of their cover in plots with Plantago. The reduction of plant diversity depended on its cover. Besides, the aboveground biomass was reduced in sites comprising Plantago. The degree of inhibition was not related to the seed size of the species found. This species reduced the incident solar radiation and the local temperature over the soil surface. The locations exhibiting such species contained lower contents of available potassium and zinc. Rhizosphere soil of P. lagopus substantially inhibited germination and growth of Amaranthus viridis, but it didn't do so for Medicago lupulina. Reduction in cover, diversity, and biomass of the urban weeds associated with P. lagopus may be related to the reduction of received solar radiation, soil temperature, and nutrient availability. The allelopathic potential of P. lagopus may have a partial role in this reduction. These results suggest that P. lagopus may create a microenvironment of new conditions not favorable for most of the coexisting species.

Grazing alters the soil nematode communities in grasslands: A meta-analysis

Grazing causes great disturbances in grassland ecosystems and may change the abundance, diversity, and ecological function of soil biota. Because of their important role in nutrient cycling and as good environmental indicators, nematodes are very representative soil organisms. However, the mechanisms by which grazing intensity, livestock type, duration, and environmental factors (e.g., climate and edaphic factors) affect soil nematodes remain poorly understood. In this study, we collected 1964 paired observations all over the world from 53 studies to clarify the grazing response patterns of soil nematodes and their potential mechanisms. Overall, grazing significantly decreased the abundance of bacterial-feeding (BF) nematodes (−16.54%) and omnivorous-predatory (OP) nematodes (−36.81%), and decreased nematode community diversity indices (Shannon–Weiner index: −4.33%, evenness index: −9.22%, species richness: −5.35%), but had no effect on ecological indices under a global regional scale. The response of soil nematodes to grazing varied by grazing intensity, animals, and duration. Heavy grazing decreased OP nematode abundance, but had no effect on the abundance of other trophic groups, or on diversity or ecological indices. Grazing by small animals had stronger effects than that by large animals and mixed-size animals on BF, fungal-feeding (FF), plant-feeding (PF) and OP nematodes, the Shannon–Wiener index, and the species richness index. The abundance of FF and OP nematodes influenced significantly under short-term grazing. The evenness index decreased significantly under long-term grazing (>10 years). Climate and edaphic factors impacted the effects of grazing on nematode abundance, diversity, and ecological indices. When resources (i.e., rain, heat, and soil nutrients) were abundant, the negative effects of grazing on nematodes were reduced; under sufficiently abundant resources, grazing even had positive effects on soil nematode communities. Thus, the influence of grazing on soil nematode communities is resource-dependent. Our study provides decision makers with grazing strategies based on the resource abundance. Resource-poor areas should have less grazing, while resource-rich areas should have more grazing to conserve soil biodiversity and maintain soil health.

Species Compotition of Fruit Bats (Pteropodidae) in Institut Teknologi Sumatera, Lampung

Fruit bats (family Pteropodidae) pollinate around 300 species of tropical plants of high economic value over a wide range of areas. This large role does not match the status of their population, which continues to decline due to habitat loss, particularly in urban areas. The Sumatra Institute of Technology (ITERA) campus, which is currently under development, may result in habitat changes that may affect bats. These concerns have led to the need for research into bat diversity on the ITERA campus. The result could be utilised to monitor and develop the environmental management of the campus. The research was conducted from May to September 2023 in five different habitat types. Data were collected using 3 mistnets and 3 night repetition each habitat. The data were analysed using indices of diversity, evenness and species richness. The study recorded 143 individuals of 7 species. The highest number of species and diversity was observed in the sengon and rubber habitat (6 species). The lowest number of species and diversity was found in the botanical garden (2 species).

Acute emergence of the intestinal pathobiome after postinjury pneumonia.

Previous preclinical studies have demonstrated sex-specific alterations in the gut microbiome following traumatic injury or sepsis alone; however, the impact of host sex on dysbiosis in the setting of postinjury sepsis acutely is unknown. We hypothesized that multicompartmental injury with subsequent pneumonia would result in host sex-specific dysbiosis. Male and proestrus female Sprague-Dawley rats (n = 8/group) were subjected to either multicompartmental trauma (PT) (lung contusion, hemorrhagic shock, cecectomy, bifemoral pseudofracture), PT plus 2-hour daily restraint stress (PT/RS), PT with postinjury day 1 Pseudomonas aeruginosa pneumonia (PT-PNA), PT/RS with pneumonia (PT/RS-PNA), or naive controls. Fecal microbiome was measured on days 0 and 2 using high-throughput 16S rRNA sequencing and Quantitative Insights Into Microbial Ecology 2 bioinformatics analyses. Microbial α-diversity was assessed using Chao1 (number of different unique species) and Shannon (species richness and evenness) indices. β-diversity was assessed using principal coordinate analysis. Significance was defined as p < 0.05. All groups had drastic declines in the Chao1 (α-diversity) index compared with naive controls ( p < 0.05). Groups PT-PNA and PT/RS-PNA resulted in different β-diversity arrays compared with uninfected counterparts (PT, PT/RS) ( p = 0.001). Postinjury sepsis cohorts showed a loss of commensal bacteria along with emergence of pathogenic bacteria, with blooms of Proteus in PT-PNA and Escherichia-Shigella group in PT/RS-PNA compared with other cohorts. At day 2, PT-PNA resulted in β-diversity, which was unique between males and females ( p = 0.004). Microbiome composition in PT-PNA males was dominated by Anaerostipes and Parasuterella , whereas females had increased Barnesiella and Oscillibacter . The PT/RS males had an abundance of Gastranaerophilales and Muribaculaceae . Multicompartmental trauma complicated by sepsis significantly diminishes diversity and alters microbial composition toward a severely dysbiotic state early after injury, which varies between males and females. These findings highlight the role of sex in postinjury sepsis and the pathobiome, which may influence outcomes after severe trauma and sepsis.

Altitudinal pattern of Odonata diversity in Kabylia (Algeria): a contrasting pattern in lotic and lentic habitats

Environmental conditions change rapidly across altitude, shaping diversity and structure of communities. Because lotic and lentic communities are often distinct and experience different environmental and anthropogenic conditions, understanding whether the diversity of these communities changes similarly across altitude is fundamental to determine how biota responds to ecological gradients in a human-dominated landscape. In this study, we carried out a comparative analysis of the altitudinal pattern of the diversity of odonates in lotic and lentic ecosystems in Kabylia (north-central Algeria) across 16 sites (eight lotic and eight lentic sites). We estimated species richness, abundance, and Shannon index as well as three environmental factors (water temperature, pH, and human disturbance) in each site. We recorded a total of 33 species (10 Zygoptera and 23 Anisoptera) with 20 species in lotic sites and 28 species in lentic sites. We recorded a similar decreasing altitudinal pattern of water temperature and human influence, but no pattern in pH. Interestingly, species richness, abundance, and Shannon index increased with altitude in lotic sites, but showed a weak negative correlation in lentic sites. These contracting patterns could be due to the interplay of a geographic gradient in anthropogenic pressure and habitat-specific species sensitivity to anthropogenic stress.

Comparison of macrozoobenthic communities and environmental variables in the subtidal zones between a nearly closed bay and an open bay

To compare the impact of human activities and geographical environment on macrozoobenthic communities in bays, four season surveys of macrozoobenthos and environmental variables in Kaozhou Bay (a nearly closed bay) and Honghai Bay (an open bay) were conducted. CLUSTER, non-metric multi-dimensional scaling (NMDS) and the relative importance index (IRI) showed that the macrozoobenthic communities were different between Kaozhou Bay and Honghai Bay. The top three dominant species in Kaozhou Bay are brackish species, including Dendronereis pinnaticirris, Euclymene annandalei and Neanthes glandicincta, while the top three dominant species in Honghai Bay are hyperhaline species, including Paraprionospio pinnata, Amphioplus laevis and Aglaophamus dibranchis. Two-way Analysis of Variance (ANOVA) showed that the species number, Shannon-Wiener diversity index, evenness index, richness index, AMBI, M-AMBI, water depth, salinity, and dissolved oxygen in Kaozhou Bay were significantly lower than those in Honghai Bay, while the concentrations of total nitrogen, total phosphorus, silicate, and mercury in Kaozhou Bay were significantly higher than those in Honghai Bay. Principal components analysis (PCA) showed that Kaozhou Bay was associated with higher concentration of total nitrogen, total phosphorus, and silicate, and Honghai Bay was characterized by deeper water, higher salinity, and higher concentration of dissolved oxygen. BIO-ENV analysis showed that water depth was the most important environmental factor affecting macrozoobenthic community in two bays. The above results showed that the species diversity index and richness index of Kaozhou Bay were lower than those of Honghai Bay because of the geographical environment difference between the two bays.

Elevation gradients alter vegetation attributes in mountain ecosystems of eastern Himalaya, India

The present study describes how vegetation (the tree layer) is shaped along the elevation gradients in the eastern part of the Indian Himalayan Region. Various vegetation attributes, distribution, population structure, and regeneration patterns of 75 tree species belonging to 31 families were studied. Tree species richness shows a low plateau (peaked between 1,300–1,500 m) with a linearly decreasing pattern above 1,500 m asl. Ericaceae was found as the dominant family, followed by Lauraceae and Rosaceae. The distributional pattern of species-to-genera ratio (S/G) did not follow any particular trends, while β-diversity increased along the elevation gradient. The Margalef index of species richness, the Menheink index of species richness, and the Fisher alpha were found to be highest at lower altitudes (1,000–1,500 m), while the Simpson index was highest at middle altitudes (2,600–3,000 m). Random distribution was shown by maximum tree species (47.3%), followed by a contagious distribution (42.9%), and regular distribution (10.8%). The regeneration of tree species was found to be good with a healthier number of seedlings (10.2%), fair (43.5%), poor (30.3%), while 16% were observed not regenerating. Acer laevigatum (1,500 m), Prunus nepalensis (3,300 m), Viburnum sympodiale (3,400 m) were among the new regenerating species at the respective altitudes. The population structure of tree species in terms of proportion of individuals in seedlings, saplings, and the adult class varied in all the elevation transects. Species with better regeneration on upper distribution limits have been recognized as probable for upward movement.

Assessment of Woody Plants Species and Ground Cover Status of Mandara Hills as Major Determinants of Wildlife Conservation

The study assessed the woody plants species and ground cover status of Mandara hills to seek necessary information for its sustenance. Information on woody plants resources and ground cover will help in the design of management strategies for wildlife conservation and biodiversity preservation. The investigation involved the identification and inventory of woody plant species, assessment of crown area and the ground cover of the Mandara hills. Woody plants’ species status was presented using species richness, frequency, species richness index and Simpson’s diversity index. Girth and height classes, ground cover and crown area were presented using percentages. 40 species of woody plants belonging to 21 families were inventoried. The species richness was highest in Kwalkuga (24) while the lowest was in Kuthu with 18. Among the woody plant’s species identified; Acacia kirkii (224) had the highest frequency, followed by Anogeissus leiocarpus (211). The highest diversity index was recorded in Kwalkuga (0.09) while Fafuma and Makwan with 0.02 each were the lowest. The majority of the trees and shrubs were recorded in the girth classes of 1.0-1.99 and 2.0-2.99 and that of height in 1.1-3.0, 3.1-5.0 and 5.1-7.0 respectively. Results of crown area showed highest value in Kwalkuga (20.92%) and Fafuma had the highest ground cover of grass (34.02%). This study recommends establishment of buffer zones where partial human activity can take place and the improvement of the livelihood of the residents to reduce human pressure on the resources of the hills.

Identifikasi Keanekaragaman Jenis Burung di Kawasan Kampus UIN Sultan Aji Muhammad Idris Samarinda Kalimantan Timur

The State Islamic University of Sultan Aji Muhammad Idris (UINSI) Samarinda is a state Islamic campus in East Kalimantan that has good vegetation conditions so there are various types of birds in the area. This research aims to know the different kinds of bird that exist in the region of UINSI Samarinda Campus so as to be a first step towards conservation efforts. The method used in this study is Point Count by observing birds at a specified location. The bird identification was done with the help of MacKinnon's books. The data obtained was analyzed by the diversity index (H’), the relative abundance index (IKR), the redness index (E), the richness index of the species and its conservation status. The results of the study obtained 16 species of birds that are known to have one species endemic to Kalimantan, namely Lonchura fuscans. The analysis of the bird's H’ value of 2.19, the highest IKR is Passer montanus of 25.89%, the E value of 0.76, and the species richness index of 3.22. In addition, the conservation status of the birds found is 14 species of birds with Least Concern status (LC), one Vulnerable status (VU) and one Endangered status. (EN).

Productivity and Species Diversity of Plant Communities Are Higher inside than outside the West Ordos National Nature Reserve, Northern China.

Nature reserves play an important role in the protection of biological habitats and the maintenance of biodiversity, but the performance and mechanisms of desert steppe nature reserves in improving plant community productivity, biodiversity and soil nutrient content are still largely unknown. To investigate the conservation effects of desert steppe nature reserve management on plant productivity and biodiversity, we compared the plant biomass, diversity and soil nutrient content inside and outside the West Ordos National Nature Reserve through sample survey, biomass determination, diversity index calculation and soil nutrient content determination. We found the following: (1) The aboveground biomass and belowground biomass of plant communities in the nature reserve were significantly larger than those outside the reserve; and the aboveground biomass of plant communities in shrub-steppe was significantly larger than that of herb grassland in both the nature reserve and the outside of the reserve. (2) The Margalef richness index, Shannon-Wiener index and Simpson index were significantly greater in the reserve than outside the nature reserve. In the desert steppe, the establishment of the nature reserve increased the α-diversity of the plant community. (3) The soil organic carbon (SOC) and soil total nitrogen (STN) were greater in the nature reserve than outside the reserve, and for the 10-20 cm and 20-40 cm soil layers, the SOC and STN were significantly greater in the core protected zone of the reserve than outside the reserve. The reserve significantly increased the nutrient content of the deeper soil layers. (4) The aboveground biomass of the plant community had a significant positive linear relationship with the species richness index, the Shannon index, and the Simpson index. There was a positive correlation between the diversity of the plant community and the soil nutrients. In summary, the nature reserve improved local plant productivity, biodiversity and the soil nutrient content, and the soil nutrient content in deeper soil layers may be the driving factor for the increase in productivity and biodiversity, which deepens our understanding of the conservation effectiveness of the nature reserve and its mechanisms.

Short-term effects of substrate surface structure on macroinvertebrates community structure and functional characteristics

Stones are one of the important natural materials in soil bioengineering and are widely used in river ecosystem restoration projects. After stones are introduced into the river channel, they become a crucial component of the riverbed substrate. Substrate is a crucial habitat for macroinvertebrates. The surface structure of substrate plays a vital role in providing habitat for a greater diversity of macroinvertebrates, thus contributing significantly to the enhancement of riverine biodiversity. This study was conducted in the headwater streams of Changbai Mountain. Complexity was introduced to the substrate surface by adding rough treatments on concrete blocks, as well as different sizes of grooves and holes. The study found that the control substrate (GK0/GT0) took the shortest time (7 d) to establish a relatively stable macroinvertebrate community. In contrast, other treated substrates required a longer time to form relatively stable communities due to the increased available living space on the substrate surface. Overall, various diversity indices were relatively higher on rough substrates compared to smooth substrates. Specifically, at 28 d, the groove-treated substrate MT1 had the highest species richness (18.67) and Shannon-Wiener diversity index (H′, 2.85), which were 2.68 times and 1.54 times higher than the control, respectively. Similarly, at 28 d, the hole-treated substrate MK1 exhibited the highest species richness (20.35) and H′ (2.84), which were 2.90 times and 1.53 times higher than the control, respectively. With the gradient changes in groove and hole sizes, macroinvertebrate species richness, density, H′, Margalef richness index (dM), and Simpson dominance index (D) on different substrates showed an initial increase followed by a decrease trend. Additionally, attached organisms were the dominant taxa on all treated substrates, with higher densities of burrowers in hole-treated substrates and more swimmers in groove-treated substrates. Substrates with larger holes favored the settlement of larger-bodied macroinvertebrates, while substrates with small grooves had higher abundances of various-sized macroinvertebrate groups. It is evident that differences in substrate surface structure have a significant impact on macroinvertebrate diversity and functional characteristics. Therefore, in river ecosystem restoration projects, adding necessary textural structures to the substrate surface can enhance the effectiveness of river ecosystem restoration.

Characterization of carbon fluxes, stock and nutrients in the sacred forest groves and invasive vegetation stands within the human dominated landscapes of a tropical semi-arid region

In the semi-arid plains of Southern India, outside the protected area network, sacred groves forests and the barren lands invaded by Prosopis juliflora are reckoned to be the major greenery, but have homogenous and heterogeneous vegetation respectively. This study attempted to compare 50 Sacred Groves Stands (SGS) and 50 monodominant Prosopis juliflora Stands (PJS) for the functional diversity, evenness, floral diversity, carbon stock and dynamics, carbon-fixing traits, dendrochronology of trees, soil nutrient profiles, and soil erosion. Quadrat sample survey was adopted to record stand density, species richness, abundance, basal area and leaf area index; composite soil samples were collected at depths 0–30 cm for nutrient profiling (N, P, K, and OC). Photosynthesis rate (µmole co2 m2/sec), air temperature (°c), leaf intracellular co2 concentration (ppm), ambient photosynthetic active radiation (µmole m2/sec), transpiration rate (m. mole H2O m2/sec) were determined for the 51 tree species existed in SGS and PJS using Plant Photosynthesis system. Structural Equation Model (SEM) was applied to derive the carbon sequestering potential and photosynthetic efficiency of eight dominant tree species using vital input parameters, including eco-physiological, morphological, and biochemical characterization. The Revised Universal Soil Loss Equation (RUSLE) model, in conjunction with ArcGIS Pro and ArcGIS 10.3, was adopted to map soil loss. Carbon source/sink determinations inferred through Net Ecosystem Productivity (NEP) assessments showed that mature SGS potentially acted as a carbon sink (0.06 ± 0.01 g C/m2/day), while matured PJS acted as a carbon source (−0.34 ± 0.12 g C/m2/day). Soil erosion rates were significantly greater (29.5 ± 13.4 ton/ha/year) in SGS compared to PJS (7.52 ± 2.55 ton/ha/year). Of the eight selected tree species, SEM revealed that trees belonging to the family Fabaceae [Wrightia tinctoria (estimated coefficient: 1.28, p = 0.02) > Prosopis juliflora (1.22, p = 0.01) > Acacia nilotica (1.21, p = 0.03) > Albizia lebbeck (0.97, p = 0.01)] showed comparatively high carbon sequestering ability.

Interactive effects of grassland utilization and climatic factors govern the plant diversity-soil C relationship in steppe of North China

The relationship between plant diversity and the ecosystem carbon pool is important for understanding the role of biodiversity in regulating ecosystem functions. However, it is not clear how the relationship between plant diversity and soil carbon content changes under different grassland use patterns. In a 3-year study from 2013 to 2015, we investigated plant diversity and soil total carbon (TC) content of grasslands in northern China under different grassland utilization methods (grazing, mowing, and enclosure) and climatic conditions. Shannon-Wiener and Species richness index of grassland were significantly decreased by grazing and mowing. Plant diversity was positively correlated with annual precipitation (AP) and negatively correlated with annual mean temperature (AMT). AP was the primary regulator of plant diversity. Grazing and mowing decreased TC levels in grasslands compared with enclosures, especially in topsoil (0–20 cm). The average TC content was decreased by 58 % and 36 % in the 0–10 cm soil layer, while it was decreased by 68 % and 39 % in 10–20 cm soil layer. TC was positively correlated with AP and negatively correlated with AMT. Principal component analysis (PCA) showed that plant diversity was positively correlated with soil TC, and the correlation decreased with an increase in the soil depth. Overall, this study provides a theoretical basis for predicting soil carbon storage in grasslands under human disturbances and climate change impacts.