Maintenance Of Biodiversity Research Articles

A saproxylic weevil acts as an ecosystem engineer: Impacts across multiple trophic levels

Although the degradation of dead trees plays an important role in biodiversity maintenance, only a few species of pioneer saproxylic beetles trigger their early degradation, thus acting as ecosystem engineers. Pioneer saproxylic beetles may be functionally more important when the properties of dead wood hinder its decay. In Patagonian rainforests, recently dead evergreen trees are massively colonized by a unique pit weevil species (Psepholax dentipes), while Nothofagus tree species host several pioneer beetle species. We evaluated if P. dentipes acts as an ecosystem engineer in evergreen trees only, positively affecting saproxylophagous beetles and Magellanic woodpeckers. We compared P. dentipes abundance between dead trees of evergreen and Nothofagus species. A causal model was used to test P. dentipes facilitation on woodpeckers and saproxylophagous beetles, while the foraging preferences of woodpeckers for trees colonized by P. dentipes were evaluated with zero-inflated models. Psepholax dentipes were more abundant in evergreen trees than in Nothofagus trees, in both cases affecting positively foraging woodpeckers. However, the positive P. dentipes effect on woodpeckers was stronger in evergreen trees than in Nothofagus trees, while a positive P. dentipes effect on saproxylophagous beetles was found only in evergreen trees. Woodpeckers selected trees with more holes of P. dentipes, but this effect weakened as trees became more decayed. Our results support the role of P. dentipes as ecosystem engineers in dead evergreen trees as they improve microhabitat conditions for saproxylophagous beetles and foraging woodpeckers, while serving as prey for woodpeckers.

Mathematical modeling of the population dynamics of a distinct interactions type system with local dispersal

Distinct biotic interactions in multi-species communities are a ubiquitous force in the natural ecosystem, and this force is an essential determinant of community stability and species coexistence outcomes. We conduct numerical simulations and bifurcation analysis of partial differential equations to gain better understanding and ecological insights into how predation (a), predator handling time (h), and local dispersal affect multi-species community dynamics. This system consists of resource-mutualist-exploiter-competitor interactions and local dispersal. From the inspection of our numerical simulations and co-dimension one bifurcation analysis findings, we discover several critical values that correspond to transcritical bifurcation, subcritical and supercritical Hopf bifurcations. This occurs as we vary the bifurcation parameters a and h in this complex ecological system under symmetric and asymmetric dispersal scenarios. Furthermore, the interplay between these local bifurcation points results in an exciting co-dimension two bifurcations, i.e., Bogdanov-Takens and cusp bifurcation points, respectively, which act as the synchronization points in this complex ecological system. From an ecological viewpoint, we find that (i) the effect of the no-dispersal scenario supports the maintenance of species biodiversity when the predation strength is moderate; (ii) symmetric dispersal induces both subcritical and supercritical Hopf bifurcation and support species diversity for moderate predation strength; and (iii) asymmetric dispersal promotes species diversity as it simplifies the bifurcation changes in dynamics by eliminating the subcritical bifurcations that trigger uncertainty, and this dispersal mechanism mediates species coexistence outcomes. Fundamentally, stable limit cycles have been reported as predator handling time varies in some ecological models; however, we observed in our bifurcation analysis the emergence of the unstable limit cycle as predator handling time changes. We discover that intense predator handling time destabilizes this complex ecological community. In general, our results demonstrate the influential roles of predation, predator handling time, and local dispersal in determining this system’s coexistence dynamics. This knowledge provides a better understanding of species conservation and biological control management.

Temporal change in floral availability leads to periods of resource limitation and affects diet specificity in a generalist pollinator.

Generalist species are core components of ecological networks and crucial for the maintenance of biodiversity. Generalist species and networks are expected to be more resilient, and therefore understanding the dynamics of specialization and generalization in ecological networks is a key focus in a time of rapid global change. Whilst diet generalization is frequently studied, our understanding of how it changes over time is limited. Here we explore temporal variation in diet specificity in the honeybee (Apis mellifera), using pollen DNA metabarcoding of honey samples, through the foraging season, over two years. We find that, overall, honeybees are generalists that visit a wide range of plants, but there is temporal variation in the degree of specialization. Temporal specialization of honeybee colonies corresponds to periods of resource limitation, identified as a lack of honey stores. Honeybees experience a lack of preferred resources in June when switching from flowering trees in spring to shrubs and herbs in summer. Investigating temporal patterns in specialization can identify periods of resource limitation that may lead to species and network vulnerability. Diet specificity must therefore be explored at different temporal scales in order to fully understand species and network stability in the face of ecological change.

Multifunctionality and diversity of livestock grazing systems for sustainable food systems throughout the world: Are there learning opportunities for Europe?

AbstractThroughout the world, livestock grazing systems (LGS) include, and provide livelihoods for, many rural populations. These LGS are represented in a wide variety of agroecological contexts and offer a huge variety of system organization. They contribute to sustainable food systems by providing multiple products including low‐cost edible proteins and energy, draft power, outputs (carbon and soil nutrient regulation, landscape and biodiversity maintenance), roles (local development support in harsh environments, contribution to the circular economy) and benefits to populations (revenue, employment, and cultural assets). These multiple functions can be described through a multifunctional conceptual model specified for LGS. Applied to cases in Africa, Asia, Latin America and Europe, the framework enables the assessment of these systems in a holistic manner that includes four dimensions: production, social, environmental and local development. These dimensions and associated local indicators demonstrate the potential important contribution that LGS may deliver to sustainable food systems. Management of interactions and trade‐offs between these functions may be improved using such a model in a multi‐stakeholder approach. Some of the functions and balance between them might have been overlooked in the consideration of European food systems.

Geology‐based and ecological processes of divergence between and within species of wingless darkling beetles

AbstractAimDiscerning the relative role of geographical and ecological factors in promoting diversification is central to our understanding of the origin and maintenance of biodiversity. We explore the roles of geology and ecological tolerance in the diversification of a group of wingless beetles with low dispersal potential.LocationWestern Mediterranean (Iberian Peninsula and North Africa).TaxonDarkling beetles (Tenebrionidae: Misolampus).MethodsWe sequenced nine gene fragments from the mitochondrial and nuclear genomes in all extant Misolampus species to reconstruct their phylogeny, evaluate species boundaries and potential contact zones and estimate divergence times. We modelled species distributions for different time periods to infer ecological preferences and assess the effects of climatic changes since the last interglacial. We used a time‐stratified process‐based biogeographical model to estimate ancestral areas of origin and the evolution of geographical ranges.ResultsThe palaeoclimatic model projections show contractions of favourable areas during the last interglacial period and mid‐Holocene, and wide stretches of suitable areas during the last glacial maximum. Analyses of ancestral bioclimatic preferences reveal ecological adaptations in isolated lineages within three species. The phylogeny of Misolampus is strongly supported and unveils deep divergences within the six species. Two well‐supported clades were recovered, one distributed in North Africa‐Balearic Islands and another in the Iberian Peninsula. The divergence between the North African and Iberian clades occurred during the early Miocene. Biogeographical analyses infer an ancestral range including the Iberian, Betic and Rifean Plates, with subsequent splits followed by dispersal events.Main conclusionsOur results favour a dual role of vicariance and dispersal in driving the historical biogeography and diversification of Misolampus since the early Miocene. We also found evidence for incipient speciation events, underscoring the role of tectonic events and adaptation to local climatic conditions in the diversification of the group.

Interconnected marine habitats form a single continental-scale reef system in South America

Large gaps in reef distribution may hinder the dispersal of marine organisms, interrupting processes vital to the maintenance of biodiversity. Here we show the presence and location of extensive reef habitats on the continental shelf between the Amazon Reef System (ARS) and the Eastern Brazilian Reef System (ERS), two reef complexes off eastern South America. Formations located 20–50 m deep include both biogenic and geogenic structures. The presence of diverse reef assemblages suggests the widespread occurrence of rocky substrates below 50 m. These habitats represent an expansion of both the ARS and ERS and the closure of the only remaining large-scale gap (~ 1000 km) among West Atlantic reef environments. This indicates that the SW Atlantic harbors a single, yet heterogeneous, reef system that stretches for about 4000 km, and thus, represents one of the largest semi-continuous tropical marine ecosystems in the world.

Earthworms regulate the nematode community by directly enhancing the bacterial-based energy channel rather than through the effect of casts

Earthworms and their casts act as biocatalysts and regulators of the biotic and abiotic processes in soil ecosystems. However, the relative importance of the presence of earthworms and earthworm casts in affecting other soil biota remains underexplored. In this study, we conducted a manipulative mesocosm experiment in a 30-year-old subtropical broadleaved plantation forest to determine how epi-endogeic earthworms (Amynthas corticis) and their casts affect soil nematode communities individually and additively. We found that the addition of the epi-endogeic earthworms significantly increased the proportion of the Ba1 guild nematodes and enhanced the enrichment index of the soil nematode community, but decreased the channel index. These results indicate that the soils become enriched in nutrients with a higher activity in bacterial-based decomposition pathways in the presence of earthworms. However, cast addition alone had a minor effect on soil nematodes. Results of a redundancy analysis suggest that elevated contents of soil ammonium and available phosphorous were the major influencing factors on soil nematode abundances in the presence of epi-endogeic earthworms. Our results indicate that epi-endogeic earthworms rather than through their casts contributed to the structuring of the nematode communities and enhancing of the bacterial-based energy channel. This finding contributes to our understanding of soil biodiversity maintenance mechanisms and how the relationship of the soil biota affects their functions in soil food webs.

Improvement of ecosystem quality in National Key Ecological Function Zones in China during 2000–2015

Improving ecosystem quality is the ultimate goal of ecological restoration projects and sustainable ecosystem management. However, previous results of ecosystem quality lack comparability among different regions when assessing the effectiveness of ecological restoration projects on the regional or national scales, due to the influence of geographical and climatic background conditions. Here we proposed a new index, ecosystem quality ratio (EQR), by integrating the status of landscape structure, ecosystem services, ecosystem stability, and human disturbance relative to their reference conditions, and assessed the EQR changes in China's counties and National Key Ecological Function Zones (NKEFZs) from 1990 to 2015. The results showed that the average ecosystem quality of China's counties deviated from the reference condition by 28%. EQR decreased by 1.2% during 1990–2000 but increased by 3.7% during 2000–2015. Those counties with increasing EQR in 2000–2015 occupy 64.7%, with obviously increasing counties mainly located in the water conservation, biodiversity maintenance, and water and soil conservation types of NKEFZs. The EQR increase in counties within NKEFZs was 3.65 times that outside of NKEFZs. Remarkable improvement of ecosystem quality occurred in the forest region in Changbai Mountain, biodiversity and soil conservation region in Wuling Mountains, and hilly and gully region of Loess Plateau, where EQR increases mainly resulted from the conversion of farmland to forest or grassland and consequent increases in ecosystem services and stability. The magnitude of EQR enhancement showed a positive relationship with the increase in forest and grassland coverage in NKEFZs. Our results highlight the important role of ecological restoration projects in improving ecosystem quality in China, and demonstrate the feasibility of the new index (EQR) for the assessment of ecosystem quality in terms of ecosystem management and restoration.

Assessing habitat connectivity in environmental impact assessment: a case-study in the UK context

ABSTRACT Ecological connectivity across landscapes is vital for the maintenance of biodiversity and the processes that enable life on earth. Despite this, environmental planning decisions are usually made at the scale of individual projects, failing to account for landscape-scale impacts. Incorporating habitat connectivity analysis in Environmental Impact Assessments (EIAs) could provide an opportunity to address this gap. We present a novel approach to model habitat connectivity in an EIA undertaken for the Heathrow Third Runway Expansion Project, a proposed development in south-east England. Drawing on field data, remote sensing, and species-specific literature reviews, a circuit theory approach was used to assess functional connectivity across the project landscape for grass snakes Natrix helvetica and soprano pipistrelles Pipistrellus pygmaeus. Results indicated key areas for species movement and potential ‘pinch-points’ vulnerable to development impacts. We discuss lessons learnt, potential applications to inform impact assessment, mitigation design, and biodiversity net gain approaches, and further work required to mainstream connectivity analyses in EIA and decision-making.

Oppressed species can form a winning pair in a multi-species ecosystem

The self-protection of alliances against external invaders is a key concept behind the maintenance of biodiversity in the face of natural selection. But since these alliances, which can be formed by different numbers of competitors, can also compete against each other, it is important to identify their strengths and weaknesses. Here, we therefore compare the vitalities of two two-species alliances whose members either beat each other mutually via a bidirectional invasion or they exchange their positions during an inner dynamics. The resulting four-species model shows rich behavior in dependence on the model parameter p, which characterizes the inner invasions, and β, which determines the intensity of site exchanges. In the low p and the large p limit, when the inner invasion becomes biased, three-member rock-scissors-paper-type solutions emerge, where one of the members is oppressed by having the smallest average concentration due to heterogeneous inner invasion rates. Interestingly, however, if we allow a more intensive site exchange between the oppressed species, they can morph into a winning pair and dominate the full parameter plane. We show that their victory utilizes the vulnerability of the rival alliance based on cyclic dominance, where a species can easily fixate a limited-size domain.

Soil salinity, not plant genotype or geographical distance, shapes soil microbial community of a reed wetland at a fine scale in the Yellow River Delta

Soil salinization is one of the most severe environmental problems restricting biodiversity maintenance and ecosystem functioning in a coastal wetland. Recent studies have well documented how salinization affects soil microbial communities along vegetation succession of coastal wetlands. However, the salinity effect is rarely assessed in the context of plant intraspecific variation. Here, we analyzed the soil bacterial and fungal communities of Phragmites australis wetland using amplicon high-throughput sequencing at a fine scale (within 1000 m) in the Yellow River Delta. Our results revealed that microbial diversity is significantly correlated to soil salinity (assessed as electrical conductivity, EC) but not to soil nutrients (N and P content) or plant intraspecific traits (leaf length, shoot height, and neutral genetic variation). Specifically, the microbial diversity tended to decrease with increased EC, and the bacterial community was more sensitive to EC change than the fungal community. The dominant bacterial phyla were Proteobacteria, Actinobacteria, and Chloroflexi, and the dominant fungal phyla were Ascomycota, Basidiomycota, and Mortierellomycota. The relative abundance of Actinobacteria was significantly negatively correlated to EC, while Proteobacteria were positively correlated to EC. In high salinity (> 1 mS/cm), the role of the stochastic processes became more important in community assembly according to habitat niche breadth estimation, neutral community model, C-score metric, and normalized stochasticity ratio. Additional common garden and microcosm experiments provided evidence that the genotype effect of P. australis on soil microbiome might only occur between lineages from different regions but not from the same region like the Yellow River Delta. Our findings provide new insights into soil microbial community assembly processes with the intraspecific variation of host plants in the wetland ecosystem and offer a scientific reference for salinity mitigation and vegetation management of coastal wetlands under future global changes.

Distribution of Breeding Population and Predicting Future Habitat under Climate Change of Black-Necked Crane (Grus nigricollis Przevalski, 1876) in Shaluli Mountains.

Simple SummaryThe black-necked crane is the only crane species that breeds on the Qinghai–Tibetan plateau, and habitat destruction and loss are the major threats to it. The Shaluli Mountains, located in a biological hotspot, is an important breeding site for the central population of the black-necked crane, but its population size and distribution, as well as shifts in distribution under climatic change, remain unknown. Therefore, we conducted a field survey and modeled the breeding black-necked crane habitat with a species distribution model in the region. The results showed that the number of breeding black-necked cranes in the area was about 200, and they were mainly distributed in a gentle meadow and wetland along the lake. Climate change will increase the potentially suitable habitat area, with a trend of northwestward expansion and upward migration, as well as an increase in habitat suitability and connectivity. In addition, more conservation gaps will arise, but the conservation role of existing protected areas will not decline. Therefore, we suggest strengthening the long-term monitoring of black-necked cranes and wetland resources in this area.Climate change is affecting biodiversity by altering the geographical distribution range of species, and this effect is amplified in climate-sensitive areas. Studying the geographic distribution of flagship species in response to climate change is important for the long-term conservation of species and the maintenance of regional biodiversity. Therefore, we collected field survey records from 2016 to 2020 and conducted field surveys of black-necked cranes in the Shaluli Mountains (SLLMs) in May–June and August–October 2021; 103 breeding records were acquired totally, and the geographical distribution range under the current and four future climate scenarios was modeled with the MaxEnt model to predict the impact of climate change on its distribution and habitat quality. The results showed that 152 black-necked cranes were surveyed in seven counties of SLLMs in total; the estimated number of black-necked cranes in the entire SLLMs was about 200. The currently suitable habitat area is 27,122 km2, mainly distributed in gentle meadows and wetland habitats along the lake where the Annual Mean Temperature is −1 °C and the Mean Diurnal Range (16 °C) and Precipitation Seasonality (105) are comparatively large. Furthermore, the breeding range would expand to varying degrees under future climate scenarios and showed a migration trend toward the northwest and higher elevation. Besides, as time goes by, the habitat for black-necked cranes in SLLMs would become more homogeneous and more suitable. The conservation effectiveness of the existing reserve network would keep stable with climate change, although there are large conservation gaps between protected areas, and these gaps will gradually expand over time. Overall, this study provides a preliminary understanding of the population and distribution and predicts the future distribution of black-necked cranes in the SLLMs. It also demonstrates the importance of SLLMs for protecting the central population of black-necked cranes and maintaining regional biodiversity. Therefore, we recommend long-term monitoring and conservation of the black-necked crane population and wetland resources in the region.

Community Assembly of Fungi and Bacteria along Soil-Plant Continuum Differs in a Zoige Wetland.

ABSTRACTDistinct plant associated microbiomes live in rhizosphere soil, roots, and leaves. However, the differences in community assembly of fungi and bacteria along soil-plant continuum are less documented in ecosystems. We examined fungal and bacterial communities associated with leaves, roots, and rhizosphere soil of the dominant arbuscular mycorrhizal (AM) plants Taraxacum mongolicum and Elymus nutans and non-AM plant Carex enervis in the Zoige Wetland by using high throughput sequencing techniques. The operational taxonomic unit (OTU) richness of fungi and bacteria was significantly higher in rhizosphere soil than in roots and leaves, and their community compositions were significantly different in the rhizosphere soil, roots, and leaves in each plant species. The co-occurrence network analysis revealed that the sensitive fungal and bacterial OTUs with various taxonomic positions were mainly clustered into different modules according to rhizosphere soil, roots, and leaves in each plant species. Along the soil-plant continuum, the rhizosphere soil pool contributed more source on bacterial than on fungal communities in roots and leaves of the three plant species, and more source on bacterial and fungal communities in leaves of T. mongolicum and E. nutans compared with C. enervis. Furthermore, the root pool contributed more source on bacterial than on fungal communities in leaves of T. mongolicum and E. nutans but not that of C. enervis. This study highlights that the host plant selection intensity is higher in fungal than in bacterial communities in roots and leaves from rhizosphere soil in each plant species, and differs in fungal and bacterial communities along the soil-plant continuum in AM plants T. mongolicum and E. nutans and non-AM plant C. enervis in the Zoige Wetland.IMPORTANCE Elucidating the community microbiome assemblage alone the soil-plant continuum will help to better understand the biodiversity maintenance and ecosystem functioning. Here, we examined the fungal and bacterial communities in rhizosphere soil, roots, and leaves of two dominant AM plants and a non-AM plant in Zoige Wetland. We found that along the soil – plant continuum, host plant selection intensity is higher in fungal than in bacterial communities in roots and leaves from rhizosphere soil in each plant species, and differs in fungal and bacterial communities in the AM- and non-AM plants. This is the first report provides evidence of different assembly patterns of fungal and bacterial communities along the soil-plant continuum in the AM- and non-AM plants in the Zoige Wetland.

PSXIII-13 Effect of Dietary Supplementation of Crushed Sasa Quelpaertensis Nakai on Growth Performance, Carcass Characteristics and Meat Quality in Landrace Pigs

Abstract This study was conducted to investigate the characteristics and physiological changes of growth performance by adding crushed Sasa quelpaertensis Nakai(SQN) to pig feed. The reason for using SQN is that SQN grows naturally under trees or at the foot of mountains and inhibits the growth of other plants, thereby preventing biodiversity maintenance. A total of 48 Landrace pigs with an average body weight of 45.11±6.16kg were assigned to four treatments with different levels of crushed SQN addition. The treatments were basal diet (control), basal diet supplemented with 2% SQN(T1), 4% SQN(T2) and 4% SQN(T2). The compound feeds were given ad libitum for 100 days. During the finishing period, the weight gain values in the four treatment groups were 111.37±3.66 kg, 109.40±3.27 kg, 106.10±3.28 kg and 103.50±3.27 kg, respectively. There was no significant difference in end-stage body weight, but the daily weight gain was 0.66±0.02kg, 0.64±0.02kg, 0.61±0.02kg, and 0.58±0.02kg, indicating that T1 was significantly (p< 0.05) greater than that of other treatment groups. Carcass characteristics were tested at 180 days of age, and the thickness of back fat in each treatment group was 21.75±1.48mm, 20.40±1.32mm, 18.60±1.32mm, and 19.20±1.32mm. The SQN-added group showed a tendency to thin back fat. In the physicochemical analysis of pig sirloin, the fat content was also significantly decreased in the SQN-added group to 3.76±0.38%, 3.52±0.39%, 2.44±0.39% and 2.79±0.39% by treatment group. In the fatty acid composition, there was a difference in linolenic acid (C18:3n3), but there was no significant difference overall. According to the results of this study, it was difficult to observe anti-obesity effect of crushd SQN because it was not digested in pigs, a unit animal. However, if the SQN extract is used, the possibility of using it as a pig feed has been confirmed, and it is judged that it can be used as a reference for the development of feed additives.

The dark side of the Common Agricultural Policy

The dark side of the Common Agricultural Policy

Disturbance–recovery dynamics inform seafloor management for recovery

Over most of the world’s estuaries, coasts, and continental shelves, key indicators of seafloor biodiversity, anthropogenic stress, and ecological sustainability emphasize the need to shift habitat management and conservation from prevention of degradation to actions focused on ecological recovery. Here we discuss the role of ecological disturbance–recovery dynamics in devising and prioritizing effective management interventions. Understanding disturbance–recovery dynamics enables assessment of possible recovery outcomes and where these may be achieved. Ecosystem networks, biodiversity landscapes, species‐specific biological traits, and location‐specific contexts provide managers with information from which likely temporal and spatial scales of recovery can be determined. On the basis of ecological theory and empirical evidence, we emphasize the potential for key species to drive the recovery or maintenance of biodiversity in marine soft‐sediment ecosystems.

Climate- and fire-smart landscape scenarios call for redesigning protection regimes to achieve multiple management goals

Integrated management of biodiversity and ecosystem services (ES) in heterogeneous landscapes requires considering the potential trade-offs between conflicting objectives. The UNESCO's Biosphere Reserve zoning scheme is a suitable context to address these trade-offs by considering multiple management zones that aim to minimise conflicts between management objectives. Moreover, in Mediterranean ecosystems, management and planning also needs to consider drivers of landscape dynamics such as wildfires and traditional farming and forestry practices that have historically shaped landscapes and the biodiversity they host. In this study, we applied a conservation planning approach to prioritise the allocation of management zones under future landscape and climate scenarios. We tested different landscape management scenarios reflecting the outcomes of climate-smart and fire-smart policies. We projected the expected landscape dynamics and associated changes on the distribution of 207 vertebrate species, 4 ES and fire hazard under each scenario. We used Marxan with Zones to allocate three management zones, replicating the Biosphere Reserves zoning scheme (“Core area”, “Buffer zone” and “Transition area”) to address the various management objectives within the Biosphere Reserve. Our results show that to promote ES supply and biodiversity conservation, while also minimising fire hazard, the reserve will need to: i) Redefine its zoning, especially regarding Core Areas, which need a considerable expansion to help mitigate changes in biodiversity and accommodate ES supply under expected changes in climate and species distribution. ii) Revisit current management policies that will result in encroached landscapes prone to high intensity, uncontrollable wildfires with the potential to heavily damage ecosystems and compromise the supply of ES. Our results support that both climate- and fire-smart policies in the Meseta Ibérica can help develop multifunctional landscapes that help mitigate and adapt to climate change and ensure the best possible maintenance of biodiversity and ES supply under uncertain future climate conditions.

Seasonal variation of vegetative stages and cysts of planktonic ciliates in a temperate coastal bay

Abstract Marine planktonic ciliates serve as a key component of the plankton food web. Their vegetative stages have frequently been studied, whereas their cyst stages have largely been ignored. Seasonal encystment and excystment of ciliates has great implications for population persistence, maintenance of biodiversity and stability of ecosystem processes. Here, we investigated seasonal variation of planktonic ciliate cysts in surface sediments of Bohai Bay, and explore the relationships between cysts and environmental factors. Eight types of aloricate ciliate cysts were identified and only two species of tintinnid cysts were recognized, namely, Favella sp. and Helicostomella longa. Abundance of ciliate cysts was lowest in winter, and highest in summer. There was a significant positive correlation between abundance of ciliate cysts and vegetative cells, which supported the viewpoint that encystment could be induced by high population density. The species composition of ciliate cysts exhibited obvious seasonal variation, and water temperature was the key driving factor. The natural encystment event of ciliates may be triggered, enhanced and terminated by a rapid variation of temperature. Our study exhibited that ciliate cysts—served as a “seed bank” for vegetative populations—were common in temperate coastal waters, and seasonal changes of ciliate cysts are crucial to vegetative population dynamics.

Assessment of Ecological Cumulative Effect due to Mining Disturbance Using Google Earth Engine

Open-pit mining and reclamation damage the land, resulting in unknown and significant changes to the regional ecology and ecosystem services. Surface mining restoration procedures necessitate a significant amount of money, typically at an unclear cost. Due to temporal and regional variability, few studies have focused on the cumulative impacts of mining activities. To investigate the ecological cumulative effects (ECE) of past mining and reclamation activities, this study continuously tracked land cover changes spatially and temporally based on phenological indices and focuses on the spatial and temporal evolution of past mining and reclamation areas using the LandTrendr algorithm. The cumulative trends of ecosystem services in the Pingshuo mining area from 1986 to 2021 were revealed using a uniform standard value equivalent coefficient. Meanwhile, the cumulative ecological effects due to essential ecosystem service functions were analyzed, including soil formation and protection, water containment, biodiversity maintenance, climate regulation, and food production. The synergistic effects and trade-offs among the functions were also explored using Spearman’s correlation coefficient. The results showed that (1) open-pit mining resulted in 93.51 km2 of natural land, 39.60 km2 of disturbed land, and 44.58 km2 of reclaimed land in the Pingshuo mine; (2) open-pit mining in the mine mainly resulted in the loss of 122.18 km2 (80.91%) of native grassland, but, through reclamation into grassland (31.30 km2), cropland (72.95 km2), and forest land (10.62 km2), the damaged area caused by mining only slightly increased; (3) the cumulative ecological value of the mining area declined by 128.78 million RMB; however, the real cumulative value per unit area was lower in the disturbance area (1483.47 million RMB) and the reclamation area (1297.00 million RMB) than in the natural area (2120.98 million RMB); (4) the cumulative value of the food production function in the study area increased, although the values of all individual functions in the study area decreased. Most of the cumulative values of services had a strong synergistic relationship. However, in the natural area, food production (FP) showed a trade-off relationship with the cumulative value of biodiversity maintenance (BM), soil formation and protection (SP), and water conservation (WC) service functions, respectively. This study constructed a methodology for analyzing mining-impacted ecosystem services using time-series processes, reproducing historically complete information for policymakers and environmental regulators.

Mitochondrial DNA cytochrome-b assisted DNA barcoding for the exploration of spatio-genetic variation among the population of Labeo rohita from different parts of India

Labeo rohita, of the Cyprinidae family, is one of the most important fish species in any aquaculture system, with immense potential in terms of both commercial production and biodiversity maintenance. Accordingly, in order to find out the spatio-genetic variation and uncover any divergence in the population structure among the Labeo rohita population, partial sequencing of the 425 bp cytochrome b (mt Cytb ) gene was carried out. The study revealed the presence of eleven haplotypes with nine polymorphic sites, of which 2 are singleton sites and six parsimony informative sites. It was observed that the haplotypes obtained from the same water system clustered separately, which suggests the variability due to the spatial distribution of the population in different environmental conditions. These detected high phenotypic differences between the rivers lead us to think and investigate that the divergent populations may have evolved over time and have been undergoing mutation. They may undergo micro-evolutionary processes and differentiate into genetically distinct sub-populations or stocks over time if reproductively and geographically isolated. Thus, the study signifies the presence of the huge biodiversity of Labeo rohita in the Indian River systems, which helps the species to adapt to the environmental changes and will also prove helpful for the breeding of new and better adaptable strains suitable for the climate change scenario.