Variation In Species Diversity Research Articles

Altitudinal Variation in Species Diversity, Distribution, and Regeneration Status of a Secondary Picea Forest in Guandi Mountain, Northern China

Altitude plays a crucial role in shaping the diversity and distribution of species in forest landscapes in mountainous regions. However, existing studies often lack comprehensive analysis of the intricate relationships among environmental factors, disturbances, and species diversity. This study aims to address this gap by thoroughly analyzing major species’ diversity, distribution, and regeneration status, along with their influencing factors, across different altitudinal gradients (1850 to 2350 m). Field surveys were conducted to examine the major species in different vegetation layers of the secondary Picea forest in Guandi Mountain. The key findings from the study include the following: (1) the study area recorded a total of nine species of adult trees, belonging to eight genera in five families, fourteen species of shrubs from eight genera in five families, and fifty-two herb species representing forty-eight genera in twenty-six families. Dominant species varied across layers, with Picea asperata Mast. and Larix principis-rupprechtii Mayr. dominating the arborous layer, Lonicera ferdinandii Franch. and Cotoneaster acutifolius Turcz. in the shrub layer, and Poa pratensis L. and Duchesnea indica (Andrews.) Focke in the herb layer. (2) Altitude significantly influenced species diversity, with the most pronounced effects observed in the shrub and herb layers. (3) Tree species regeneration varied with altitude, with Picea asperata exhibiting the highest regeneration performance, particularly in the high-altitude zone (2250–2350 m). Regeneration parameters were significantly correlated with species diversity indices in both tree and shrub layers. (4) Redundancy analysis revealed that, apart from altitude, cutting (p = 0.015) influenced the species diversity of the tree layer, while annual precipitation (p = 0.006) and temperature (p = 0.01) determined the diversity of the shrub layer. Grazing (p = 0.042) was identified as a determining factor for species diversity in the herb layer. Overall, these findings provide valuable insights into the sustainable management of forest ecosystems in the study area and offer practical guidance for forest management in similar mountainous landscapes worldwide.

Evolutionary causes of global patterns of species richness in regional fern floras across the world

AbstractAimGlobally, biodiversity is unevenly distributed, as a result of varying environmental conditions and regionally different historical processes. The influence of the latter on current diversity patterns is poorly understood. We explore geographic patterns of matches and mismatches between phylogenetic relatedness metrics measuring different depths of evolutionary history and investigate the effects of evolutionary legacy at different evolutionary depths on species density of ferns.MethodsWe divided the globe into 392 geographic regions on land, and collated species lists of ferns for each geographic region. We related species richness to phylogenetic metrics reflecting different depths of evolutionary history (standardized effect sizes of mean nearest taxon distance and mean pairwise distance, MNTDses and MPDses, respectively) for ferns in regional floras across the world.LocationGlobal.Time PeriodCurrent.TaxonFerns.ResultsWe show that different centers of fern diversity have strikingly different phylogenetic composition. We find that overall fern species diversity is negatively correlated with both MNTDses and MPDses, so that regions with high species diversity tend to have clustered species assemblages, whereas species‐poor regions tend to have overdispersed species assemblages. At the global extent, MNTDses and MPDses together explained 62.2%, 19.3%, and 65.7% of the variation in species diversity for all ferns as a whole, non‐polypod ferns, and polypods, respectively.Main ConclusionsOur study suggests that current geographic patterns of fern species richness are driven, at least in part, by evolutionary history of ferns, which varies among biogeographic regions.

Height-diameter model of broad-leaved mixed forest based on species classification in Maoershan, Northeast China.

The complex stand structure and high species diversity of natural forests pose great challenges for analyzing stand growth and formulating reasonable plans for forest management. The height-diameter relationship is of great significance for predicting stand growth and formulating forest management measures. Based on survey data of 48 broad-leaved mixed forest plots in Maoershan, we classified 23 tree species into four groups based on species structure, growth characteristics and bionomics. We established a generalized model including stand, tree competition, species mixing and species diversity variables by reparameterization method, and a two-level mixed effect model of plot and tree species group. We tested the prediction ability of the model by leave-one-out cross-validation method. The results showed that the Ratkowsky (1990) model was the optimal basic model. The introduction of dominant height, basal area of trees larger than the object tree, basal area proportion of each species, and Shannon index could better explain the height-diameter relationship of broad-leaved mixed forest in Maoershan. The introduction of the mixed effect model of plot and tree species group could significantly improve the prediction accuracy of the model, with a Ra2 of 0.83. Under the same gradient of environmental factors, intolerant tree species exhibited higher tree heights than shade-tolerant tree species. In this study, we used the constructed tree height-diameter model to analyze the effects of species mixing and tree functional traits on tree height, which provided a theoretical basis for accurately predicting height of different tree species and analyzing the growth relationships in broadleaved mixed forests.

Diversity and botanical composition of native species in the Pampa biome in vineyards cultivated on soils with high levels of copper, zinc and manganese and phytoremediation potential

Viticulture allows the preservation of native species inside vineyards in the Pampa biome. However, phytosanitary treatments in these areas can increase the levels of Cu, Zn and Mn. The study aimed to (i) verify the influence of Cu, Zn and Mn contents in Pampa biome soils; (ii) identify variables related to Cu, Zn and Mn that most contribute to the variation in richness, diversity, and dry matter production of native vegetation, (iii) investigate the phytoremediation potential of species present in vineyards. Botanical composition, Cu, Zn, Mn available in the soil, and plant nutritional composition in two vineyards (V1 and V2) and native field (NF) were evaluated. Vineyards showed higher Cu, Zn and Mn contents in the soil, resulting in the lowest biomass, richness, and diversity of native species. Mn in tissue was the most important variable in explaining the variation in dry matter. Zn in the soil helped to explain the difference in species richness and diversity. P concentration in tissue was important in elucidating the variation in species diversity. Paspalum plicatulum and Paspalum notatum have potential for phytostabilization of metals in vineyards.

Spatio-temporal variation of species richness and phylogenetic diversity patterns for spring ephemeral plants in northern China

Understanding the spatiotemporal distribution of species diversity in response to climatic change is essential for the conservation and management of species resources. Spring ephemeral plants (SEs) have played a crucial role in sustaining the desert and woodland ecosystems of northern China. However, our knowledge regarding the spatiotemporal variation of species diversity in SEs is limited. In this study, we employed occurrence and phylogenetic data for 200 SEs, alongside 19 environmental variables, to model their geographical distribution during the Last Glacial Maximum (LGM), Current, and the year 2070 (considering two representative concentration pathway scenarios, SSP2–4.5 and SSP5–8.5). We also visualized the phylogenetic diversity patterns in the Current. Our findings revealed that more than half of the SEs notably expanded their range and continuously shifted northeastward from LGM to 2070. From LGM to Current and from Current to SSP2–4.5_2070, 64% and 54% of SEs shifted from higher to lower elevations, and 53% of them will slightly shift to higher elevations from Current to SSP5–8.5_2070. We identified three distinct bioregions corresponding to the core ranges of desert SEs and understory SE ecotypes. The Ili Valley, Tacheng Basin, northern and southern Junggar Basin, and Changbai Mountains were identified as hotspots for species richness, phylogenetic diversity, and endemism for the two SE ecotypes. Notably, these hotspots had limited overlap with existing nature reserves. Additionally, the suitable habitat of desert SEs was primarily determined by precipitation seasonality and precipitation of driest month, whereas the distribution of forest understory SEs was mainly influenced by annual precipitation and temperature seasonality. This study significantly contributes to a comprehensive understanding of the modern diversity distribution patterns and conservation priorities for SEs within a species distribution and phylogenetic framework.

Flies in the high for floral hike? Altitudinal variation in species diversity and composition of Diptera (Insecta) in the eastern Himalaya, India

Species diversity and composition enable us to understand the conservation and management of an ecosystem. There is scarcity of knowledge in understanding the diversity change across the gradients of elevation, especially in the Himalaya. Here, we focused in the eastern Himalaya to investigate the patterns of taxonomic and functional diversity of true flies with relation to variation in altitude. The study was conducted in protected area (Neora Valley National Park) in the eastern Himalaya, India and the survey was conducted at five altitudinal zones (from 500 to 3,000 m). A total of 201 species of Diptera, with 105 genera and 33 families were recorded, of which 25 species are new to the state of West Bengal and eight species are new to India. The species diversity increased with elevation (maximum was near 2,500 m) and most of the flies preferred to be close to bushes with flowers, with a substantial percentage of them being pollinator species. Flies adapt to the various vegetation and climate patterns, which was evident by the abundance of fly species at high altitudes (1,500–2,500 m). Hence, it is very important to implement appropriate actions to protect the diversity of true flies in this Himalayan landscape.

Variations in species diversity and the role of butterflies in oil palm agroecosystems at PT BSM South Sumatra

Reducing the use of chemical fertilizers and controlling pests/chemical diseases is one of the prerequisites for the realization of sustainable oil palm plantation management. In line with that, the paradigm of green economic development requires optimizing the utilization of biodiversity in various aspects of managing oil palm plantations in Indonesia. Therefore, research is needed that can describe the variation and role of biodiversity (one of which is butterfly taxa) in the agro-ecosystem of oil palm plantations. This study aims to identify variations in species diversity and the role of butterflies in the agro-ecosystem of oil palm plantations. Observation of butterfly species diversity was carried out on seven types of oil palm plantation land cover at PT BSM. The method used is pollard transect (2 km with a width of 10 m) and trapping. The role of various types of butterflies is carried out through a literature search. The results showed that there were 163 individuals from 30 species and consisted of 4 families namely Papilionidae, Pieridae and Lycaenidae. The highest diversity and richness index values were found in smallholder plantations 1 (H′=2.42) and (Dmg=4.01), while the lowest were found in young oil palm areas (H′=0.87) and (Dmg=0. 99). The highest evenness index value was found in shrubs (E=1) while the lowest was in young oil palm land cover (E=0.54). Butterfly species that have potential as environmental bioindicators are Tanaecia pelea, Neptis hylas, Cupha erymantis, Neptis ida, Danaus affinis, Junonia atlites, Leptosia nina, Catopsilia pyranthe, Rapala iarbus, Papilio memnon, Losaria coon, Papilio polytes, Spindiasis lohita and Eurema hecabe. While the pollinators are Ypthima baldus, Catopsilia pyranthe, Hypolimnas bolina, Papilio polytes, and Neptis hylas.

Elevation patterns of tree diversity, composition and stand structure in Mahendragiri Hill Forest, Eastern Ghats of Odisha, India

Tropical mountain forests in Eastern Ghats provide a unique opportunity to relate environmental drivers to plant community structure along elevation gradient. We aimed to investigate the tree diversity, composition and stand structure along elevation gradient and drivers facilitating species distribution across Mahendragiri Hill Forest (MHF) in Eastern Ghats of Odisha, India. Altogether 120 plots of 0.05 ha were established and stems ≥10 cm diameter at breast height were measured. We compared species composition and stand structure among elevation zones. Ordination analysis was used to quantify how community structure was related to topographic, climatic and onsite conditions. In total 189 species representing 131 genera and 51 families were recorded ranging from 64 (MHF6) to 106 species (MHF4). Fabaceae representing 23 species, followed by Phyllanthaceae was dominant families. Maximum tree density and basal area were enumerated in high elevation MHF6 and least disturbed MHF5, respectively. Canonical Correspondence Analysis (CCA) interpreted 58.59% of variation and depicted the role of elevation followed by disturbance and precipitation in species distribution patterns. Variance partitioning analysis shows that topography and disturbance strongly partitioned the dissemination of tree species. Variations in species diversity reflects a direct coupling or interaction of several factors together, making it a complex phenomenon.

Comparison of the nutrient value, nonspecific immunity, and intestinal microflora of red swamp crayfish (Procambarus clarkii) in different culture modes

This study aimed to compare the nutritional composition, digestive enzyme activity, nonspecific immunity, and intestinal microflora of Procambarus clarkii under different culture modes: crayfish and crab coculture, pond intensive farmed culture (PF), rice and crayfish coculture (RC), cement pond culture (CP), and wild-caught. The muscle, hepatopancreas, and intestine of crayfish with a mean weight of 25.35 ± 4.23 g were collected and examined. The results showed that the nutritive value of amino acids and fatty acids in the muscle was higher in the RC group than in the other groups. Moreover, muscle crude protein contents were the highest in the CP group. Trypsin activities in the intestines were significantly higher in the PF and CP groups than in the other groups (P < 0.05). The alkaline phosphatase (AKP) and acid phosphatase (ACP) activities of the PF group were the lowest, whereas the CP group showed high AKP and ACP activities and low malondialdehyde levels. The dominant bacterial communities in the intestine of P. clarkii included Proteobacteria, Bacteroidetes, Firmicutes, RsaHF231, Tenericutes, and Planctomycetes at the phylum level and ZOR0006, Candidatus Bacilloplasma, and Aeromonas at the genus level. These results suggested that the dominant bacterial community phyla and genera in the intestine varied greatly between the culture modes. The results of principal coordinate analysis based on the operational taxonomic unit level showed that the bacterial community distribution in the CP group was quite different from that in the other groups, indicating dramatic variations in species diversity. Our current findings will provide a theoretical foundation for understanding the association between the culture modes of P. clarkii and nutrition, immunity, and intestinal microflora.

Community structure and species diversity dynamics of a subtropical evergreen broad-leaved forest in China: 2005 to 2020

Here, we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in China. We found that community structure in this forest changed over a 15-year period. Specifically, renewal and death of common species was large, with the renewal of individuals mainly concentrated within a few populations, especially those of Aidia canthioides and Cryptocarya concinna. The numbers of individual deaths for common species were concentrated in the small and mid-diameter level. The spatial distribution of community species diversity fluctuated in each monitoring period, showing a more dispersed diversity after the 15-year study period, and the coefficient of variation on quadrats increased. In 2010, the death and renewal of the community and the spatial variation of species diversity were different compared to other survey years. Extreme weather may have affected species regeneration and community stability in our subtropical monsoon evergreen broad-leaved forests. Our findings suggest that strengthening the monitoring and management of the forest community will help better understand the long- and short-term causes of dynamic fluctuations of community structure and species diversity, and reveal the factors that drive changes in community structure.

Responses of diversity and morphometric traits of ground beetles to soil chemical properties in industrial city of China

Industrial and agricultural activities result in the direct release of contaminants into soil, which alters and destructs the habitats of soil biota. Clarifying the effects of soil contamination on soil organisms can provide a theoretical basis for the conservation of soil organisms. In this study, 3 nonmetal elements (total C, total N, total P), 5 light metal elements (total K, Ca, Mg, Al, Na), 5 heavy metal elements (Fe, Hg, Pb, Mn, Zn) and soil pH, and 18 morphological traits of carabid species were analysed to explore the responses of spatial variation of species diversity, community composition and morphometric traits to differences of soil chemical properties in four sites (Cement Plant, Coal Coking Plant, Village and Nature Reserve) in Gujiao City, the largest coking coal production city of China. In total, 1095 carabid beetles representing 59 species were recorded, with the greatest richness and activity abundance of ground beetles were found in Cement Plant and the largest species diversity was found in Coal Coking Plant, Nature Reserve contained carabid assemblages distinct from the other three sites. As for species distribution, 14 soil chemical properties could be associated with 43.2% of the observed variation, with soil Zn, N, Ca and Mn being the most important in explaining the spatial variation of the species. Changes in the type of economic activity had a significant influence on the 18 morphometric traits of carabid species, species of Coal Coking Plant and Nature Reserve had larger morphological traits than the other two sites. Variations in morphometric traits showed a significant correlation with soil chemical properties, especially body wide and profemora length, with 14 soil factors explaining more than 60% of their variance. Soil Mg, Mn, total N and pH value contributed the most in explaining morphometric traits variability of ground beetles. In summary, changes in soil chemical properties due to industrial and agricultural activities have led to carabid species diversity, community and morphometric traits changes. Soil health management is prerequisites that contribute to conserve soil biodiversity and function in industrial areas.

Seasonal and Periodical Assessment of the Abundance and Diversity of Epigaeic Invertebrates in an Urban Forest Remnant, Dar es Salaam, Tanzania

Urban Forest (UF) refers to a complex human-environment system encompassing urban and peri-urban vegetation such as gardens, rivers and coastal corridors, and uninhabited yards. Human beings benefit from a healthy UF in a variety of ways such as recreation, disasters management, and the lessening of the effects of environmental deterioration (caused by the ongoing anthropogenic activities) like air pollution and ozone concentration affecting many epigaeic fauna. Epigaeic Invertebrates (EIs) are above ground foraging or litter dwelling invertebrates carrying important roles in UFs ecosystems such as ecosystem engineers and pests’ natural enemies. The present study assessed the influence of dry and wet seasons and different periods of a day (morning, afternoon, and evening hours) towards the abundance and diversity of ground dwelling invertebrates around urban forest remnant in Dar es salaam city, Tanzania. Data collection used pitfall trap, baited traps, and dry leaf litter sifting methods. A total of 10,363 EIs individuals were collected with 133 morpho species, 87 families and 18 orders (Hymenoptera dominated by 71.4%). Wet season had significantly higher abundance (6,360 individuals with 121 morpho species) than dry season (4,003 individuals and 88 morpho species), possibly due to the higher availability of food resources during rainy times. However, quite unexpectedly dry season had higher species diversity, probably due to the over dominance of a very aggressive Formicidae species in wet season that displaced some intolerable species. Also, the overall variations of species diversity and abundance between morning, afternoon, and evening hours were significantly different but higher in the morning. This suggested that EIs were active at different times of the day but were more attracted to the morning sunshine and decreased as the land became hotter. This study depicts urban forests to be among world ecosystems with relatively high levels of EIs biodiversity and hence an urgent call for their conservation efforts before it is too late.

Gut Microbiota and Behavioural Issues in Production, Performance, and Companion Animals: A Systematic Review.

The literature has identified poor nutrition as the leading factor in the manifestation of many behavioural issues in animals, including aggression, hyperalertness, and stereotypies. Literature focused on all species of interest consistently reported that although there were no significant differences in the richness of specific bacterial taxa in the microbiota of individual subjects with abnormal behaviour (termed alpha diversity), there was variability in species diversity between these subjects compared to controls (termed beta diversity). As seen in humans with mental disorders, animals exhibiting abnormal behaviour often have an enrichment of pro-inflammatory and lactic acid-producing bacteria and a reduction in butyrate-producing bacteria. It is evident from the literature that an association exists between gut microbiota diversity (and by extension, the concurrent production of microbial metabolites) and abnormal behavioural phenotypes across various species, including pigs, dogs, and horses. Similar microbiota population changes are also evident in human mental health patients. However, there are insufficient data to identify this association as a cause or effect. This review provides testable hypotheses for future research to establish causal relationships between gut microbiota and behavioural issues in animals, offering promising potential for the development of novel therapeutic and/or preventative interventions aimed at restoring a healthy gut-brain-immune axis to mitigate behavioural issues and, in turn, improve health, performance, and production in animals.

Ammonia Influences the Zooplankton Assemblage and Beta Diversity Patterns in Complicated Urban River Ecosystems

Beta diversity represents the spatial or temporal variation of species diversity among sampling sites and may be composed of two elements: turnover (Brepl, replacement of species assemblages) and nestedness (Brich, loss or gain of species assemblages). Knowledge of the mechanisms driving beta diversity contributes to an understanding of the variation in aquatic ecosystem community structures. We sampled zooplankton assemblages at 24 sites in 11 rivers in Shanghai City and conducted a nutrient addition experiment to elucidate the effects of various environmental variables on the community structure and beta diversity patterns of the zooplankton. The zooplankton assemblages in the rivers differed significantly at ammonia nitrogen (NH3-N) concentrations below (Group I) and above (Group II) 1.03 mg·L−1. The nutrient addition experiment further demonstrated that the composition of the zooplankton assemblages changed markedly along an ammonia concentration gradient (0.2 to 5.0 mg N·L−1). The total beta diversity of Group I was considerably higher than that of Group II, indicating that high nutrient (ammonia) pollution led to biotic homogeneity. Overall, turnover was the key factor determining the total beta diversity of the two groups, suggesting the key importance of replacement of zooplankton assemblages. Furthermore, we found a correlation between environmental factors (mainly nitrogen content) and the beta diversity of zooplankton, and beta diversity (Brepl and Btotal) decreased with increasing trophic state. These findings provide further insight into the changing characteristics of the beta diversity patterns of zooplankton in river networks and may help to guide managers dealing with conservation strategies for aquatic biodiversity preservation in urban river ecosystems.

Application and Comparison of Different Models for Quantifying the Aquatic Community in a Dam-Controlled River.

In order to develop a better model for quantifying aquatic community using environmental factors that are easy to get, we construct quantitative aquatic community models that utilize the different relationships between water environmental impact factors and aquatic biodiversity as follows: a multi-factor linear-based (MLE) model and a black box-based 'Genetic algorithm-BP artificial neural networks' (GA-BP) model. A comparison of the model efficiency and their outputs is conducted by applying the models to real-life cases, referring to the 49 groups of seasonal data observed over seven field sampling campaigns in Shaying River, China, and then performing model to reproduce the seasonal and inter-annual variation of the water ecological characteristics in the Huaidian (HD) site over 10 years. The results show that (1) the MLE and GA-BP models constructed in this paper are effective in quantifying aquatic communities in dam-controlled rivers; and (2) the performance of GA-BP models based on black-box relationships in predicting the aquatic community is better, more stable, and reliable; (3) reproducing the seasonal and inter-annual aquatic biodiversity in the HD site of Shaying River shows that the seasonal variation of species diversity for phytoplankton, zooplankton, and zoobenthos are inconsistent, and the inter-annual levels of diversity are low due to the negative impact of dam control. Our models can be used as a tool for aquatic community prediction and can become a contribution to showing how quantitative models in other dam-controlled rivers to assisting in dam management strategies.

Global patterns of taxonomic and phylogenetic diversity of flowering plants: Biodiversity hotspots and coldspots

Species diversity of angiosperms (flowering plants) varies greatly among regions. Geographic patterns of variation in species diversity are shaped by the interplay of ecological and evolutionary processes. Here, using a comprehensive data set for regional angiosperm floras across the world, we show geographic patterns of taxonomic (species) diversity, phylogenetic diversity, phylogenetic dispersion, and phylogenetic deviation (i.e., phylogenetic diversity after accounting for taxonomic diversity) across the world. Phylogenetic diversity is strongly and positively correlated with taxonomic diversity; as a result, geographic patterns of taxonomic and phylogenetic diversity across the world are highly similar. Areas with high taxonomic and phylogenetic diversity are located in tropical regions whereas areas with low taxonomic and phylogenetic diversity are located in temperate regions, particularly in Eurasia and North America, and in northern Africa. Similarly, phylogenetic dispersion is, in general, higher in tropical regions and lower in temperate regions. However, the geographic pattern of phylogenetic deviation differs substantially from those of taxonomic and phylogenetic diversity and phylogenetic dispersion. As a result, hotspots and coldspots of angiosperm diversity identified based on taxonomic and phylogenetic diversity and phylogenetic dispersion are incongruent with those identified based on phylogenetic deviations. Each of these metrics may be considered when selecting areas to be protected for their biodiversity.

Bird diversity-environment relationships in urban parks and cemeteries of the Neotropics during breeding and non-breeding seasons

BackgroundUrbanization will increase in the next decades, causing the loss of green areas and bird diversity within cities. There is a lack of studies at a continental scale analyzing the relationship between urban green areas, such as parks and cemeteries, and bird species richness in the Neotropical region. Bird diversity-environment relationships in urban parks and cemeteries may be influenced by latitudinal gradients or species-area relationships. However, the seasonal variation of species diversity- environment has not been analyzed at a continental scale in the Neotropics.MethodsBird surveys were conducted in 36 cemeteries and 37 parks within 18 Neotropical cities during non-breeding and breeding seasons. Bird diversity was assessed through Hill numbers, focusing on species richness, the effective number of species derived from Shannon index and the Simpson index. Environmental variables included latitude, altitude, and local scale variables such as area size, habitat diversity and pedestrian traffic.ResultsSpecies richness and Shannon diversity were higher during the breeding season, whereas Simpson diversity did not vary between seasons. During both seasons, species richness increased with area size, was negatively related to altitude, and was the highest at 20° latitude. Species richness was also positively related to habitat diversity, pedestrian traffic, and was highest in suburban areas during the non-breeding season. Shannon and Simpson diversity showed significant relationships with habitat diversity and area size during the breeding season. Bird diversity was similar between parks and cemeteries.DiscussionOur results showed that urban parks and cemeteries have similar roles in conserving urban bird diversity in Neotropical cities. However, species diversity-environment relations at the continental scale varied between seasons, highlighting the importance of conducting annual studies.

Precipitation amount and event intervals interact to change plant diversity during dry years in a desert shrubland

Variations in species diversity and soil properties in response to future climate change is a key focus area in ecological research. The influence of precipitation amount on plant community diversity and soil properties, in sandy desert ecosystems, is poorly studied. We chose the Artemisia ordosica community to examine how diversity, and the physical and chemical properties of soil vary in response to changes in precipitation. An in situ experimental platform was used to simulate total monthly precipitation at specific intervals in a desert-grassland region of northern China. The influence of precipitation on the community was investigated using three precipitation amount levels and two intervals. The relative density, coverage, and frequency of species in each experimental quadrat was analyzed for evaluating the community structure. Results showed that variability in precipitation amounts and intervals altered the species diversity in the A. ordosica communities. Increased precipitation amount enhanced whole community’s species diversity via improving the richness of perennial forbs. Lengthening the precipitation intervals enhanced whole community’s species diversity in the context of low precipitation amount but reduced species diversity in high precipitation amount condition. The precipitation patterns affected community species composition and diversity mainly by controlling soil moisture, secondly by changing the nitrogen and organic matter content of the surficial soils. This study revealed that effects of precipitation interval on the species diversity depended on annual precipitation amount and offer an innovative insight to evaluating the succession of desert ecosystems in the context of precipitation change in the future.

Long-term monitoring dataset of fish assemblages in rocky tidepools on the southern coast of Taiwan

Long-term data of fish assemblages collected in the rocky intertidal zone provides a valuable resource for elucidating the temporal variations in species diversity and intertidal ecosystems. In this study, we describe a long-term time-series dataset of fish collected by counting the number of anesthetized fish at sampling stations in the rocky tidepools on the southern coast of Taiwan. The species assemblages were monitored seasonally at the two stations for 16 y (2000–2008 and 2012–2018). In total, 86 samples containing 5137 individuals belonging to 82 species were recorded. Our data can be used for elucidating the temporal variations in fish assemblages and intertidal ecosystems and as background information for the resilience of the fish community conservation in coastal areas. The current study presents valuable data for researchers to understand the temporal and spatial variations in species abundance, richness, diversity, and composition in relation to climate change, environmental factors, and human activities.

Variation model of north-south plant species diversity in the Qinling-Daba Mountains in China

Understanding the variation patterns of mountain plant species diversity is becoming increasingly important in forest ecosystem management and protection. However, the research on plant species diversity has mainly focused on changes in whole plant species. Therefore, an in-depth study of the change mode of plant species via different classification methods and its impact on the overall change in plant diversity is very important for forestland restoration and biodiversity protection. In this study, the Qinling-Daba Mountains, a major feature of China's north–south transitional zone, were selected as the study area. Based on the floristic data of 58 nature reserves in the Qinling-Daba Mountains and its adjacent areas, the north–south change patterns of plant orders, families, genera and species diversity were first analyzed. Second, plant species were divided into different groups according to taxonomic group (orders, families and genera), life form (trees, shrubs and herbs) and endemism (species endemic and nonendemic to China). The change patterns of each group in the north–south direction were analyzed. Finally, the effects of different groups on the north–south change patterns of whole species are discussed. The species diversity of orders, genera and species exhibited a typical latitudinal gradient pattern, specifically, it gradually decreases from south to north, but the species diversity is relatively scattered. According to the north–south variation in species diversity in each order, families and genus, 5% of the orders, 2% of the families and 6% of the genera were positively correlated with latitude, and the rest were negatively correlated or uncorrelated. According to the north–south variation patterns of different life forms, the diversity of trees and shrubs showed a bimodal Gaussian distribution with latitude. According to the north–south variation patterns of plant endemism, the diversity of endemic species showed a Gaussian distribution with latitude, but the diversity of nonendemic species was negatively correlated with latitude. The dispersion of whole species diversity is caused by species in a few orders, families and genera, trees and shrubs, and endemic species. They may be more strongly affected by the vertical zonality of the mountains, which is inconsistent with the typical latitude gradient model. Our research will provide a basis for forestland management, nature reserve establishment and biodiversity conservation. • We examined a latitudinal gradient model of plant diversity in the Qinling-Daba Mountains. • The latitudinal gradient patterns of a few taxa are inconsistent with the typical patterns. • The relationships between tree and shrub diversity and latitude have Gaussian distributions. • Qinling-Daba Mountains is one of distribution areas of species endemic to China.