Effective Number Of Species Research Articles

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.

Back to the Future: Agricultural Booms, Busts, and Diversification in Maine, USA, 1840–2017

In temperate forested regions, historical agricultural production and value have been characterized by booms and busts. Agricultural diversification can encourage more stable agricultural development in the future. Agricultural Census and Survey data from 1840 to 2017 were used to estimate crop and livestock species’ product production and value for Maine, USA. These data were also used to calculate agricultural diversity indicators over time such as species richness, relative abundance, effective number of species, species diversification index, evenness, Shannon-Weiner index, and composite entropy index. Maine’s historical grass-based livestock systems included crops raised to feed livestock from the state’s establishment until the 1950’s. Since the 1950’s, production and value of livestock commodity products (e.g., meat chicken, eggs) have busted after initial booms. Three categories where diversity indicators have become more favorable since the 1950’s in Maine include livestock, livestock forage/feed, and potatoes and potato rotation crops. Mixed vegetables, fruits, nuts, and specialty crops as a category have had diversity increases during the 1970’s back-to-the-land movement and over the past two decades. Floriculture, propagation, and X-Mas trees as a category have witnessed volatile diversity indicator changes over time. Past diversification strategies can inspire farmers to go “back to the future” to improve sustainability.

Understandable multifunctionality measures using Hill numbers

In ecology, multifunctionality metrics measure the simultaneous performance of multiple ecosystem functions. If species diversity describes the variety of species that together build the ecosystem, multifunctionality attempts to describe the variety of functions these species perform. A range of methods have been proposed to quantify multifunctionality, successively attempting to alleviate problems that have been identified with the previous methods. This has led to a proliferation of more‐or‐less closely related metrics which, however, lack an overarching theoretical framework. Here we borrow from the comprehensive framework of species diversity to derive a new metric of multifunctionality. Analogously to the effective number of species used to quantify species diversity, the metric we propose is influenced both by the number of functions as well as, crucially, the evenness of performance levels across functions. In addition, the effective multifunctionality also considers the average level at which the functions are performed. The result is a measure of the cumulative performance of the system were all functions provided equally. The framework allows for the inclusion of the correlation structure among functions, thus allowing it to account for non‐independence between functions. We show that the average metric is a special case of the newly proposed metric when all functions are uncorrelated and performed at equal levels. We hope that by providing a new metric of multifunctionality anchored in the rigorous framework of species diversity based on effective numbers, we will overcome the considerable skepticism that the larger community of ecologists has built against indices of multifunctionality. We thereby hope to help popularize this important concept which, like biological diversity, describes a fundamental property of ecosystems and thus lies at the heart of ecology.

Taxonomy, distribution and statistical ecology of black mildews fungi reported from Maharashtra state of India

Abstract. Dubey R, Moonambeth N, Pandey AD. 2022. Taxonomy, distribution and statistical ecology of black mildew fungi reported from Maharashtra state of India. Asian J For 6: 97-125. The Maharashtra state of India represents some of the best non-equatorial tropical forests in the world. It supports many endemic species of plants, animals, and microorganisms, especially in the Western Ghats, India. Moreover, a research project entitled "Foliicolous fungi of Maharashtra" was allotted by the Botanical Survey of India, Ministry of Environment, Forests, and Climate change, India, to carry out the mycological studies. As part of this project, ongoing studies were carried out on black mildew fungi of this state. The present studies offer a taxonomic account, distribution, and ecological parameters of 72 black mildew taxa collected from different areas of Maharashtra state of India. The present study provides three new records of fungi to India, 31 new host records to India, 40 new records of fungi to the Maharashtra state of India, and one new variety, viz., Asterina jasmini Hansf. var. koyani var.nov., depicted by checklist and Figures. In addition, a comprehensive table containing information on location, date of collection, name of the collector, and new records are given for ready reference. During this study, Meliola was the dominant genus with 35 species, whereas Meliolina mollis was the dominant taxon obtained from a maximum of 5 collections. More than 90% of black mildew species are collected from the Western Ghats Districts. In diversity indices, Gini-Simpson's was 0.9818, and Shannon's was 4.1668. Pielou's evenness index was 0.9743, causing true diversity, calculated as an effective number of species (64), to be less than observed species richness (72).

Surf and turf. Animal resources in the human diet in Cantabrian Spain during the Mesolithic (11.5 – 7.5 Ky cal. BP)

The beginning of the Holocene involved a series of climatic and environmental changes that affected the ways of life of the last hunter-gatherers. In the case of the Spanish Cantabrian region, these changes transformed the material culture and the way human groups interacted with the environment and, therefore, the subsistence strategies of the end of the Upper Pleistocene. In terms of the use of faunal resources, this period was characterised by an increase in the exploitation of coastal resources, mainly molluscs, but also crustaceans and echinoderms, which make up the so-called “shell middens”, while at the same time the percentage of macromammals was reduced and animals considered to have a “low energy range” were introduced into the diet. In this paper we assess the role played by each of these animal resources in the subsistence of Mesolithic human groups, determining their nutritional contribution and establishing a prey ranking based on the caloric intake of each resource. For this purpose, we collected archaeofaunal data from 14 sites from recent archaeological excavations with levels dated between ca. 11.5 and 7.5 ky cal BP in which the consumption of vertebrates and invertebrates is documented. At each of these sites we analysed diversity, homogeneity and species richness using Simpson's and Shannon's indexes, as well as the effective numbers of species for terrestrial and coastal resources, assessing the relationship between the two. With the palaeoecological and palaeoeconomic data from these archaeological sites (most of them located in caves), we estimate the weight that the different animal resources consumed by the last hunter-gatherer communities of the Cantabrian region had in their diet.

Quantitative status of population of insects from Lucknow region, Uttar Pradesh, India

Insects are found everywhere in our nature, yet, their diversity, abundance and characterization in various ecosystems are still not well defined, systematically. The present study was conducted to assess and compare the abundance, species richness and diversity of insects amongst four different spots of Lucknow district, Uttar Pradesh, India. A total of 746 insects which belonged to 6 insect species and 3 insect orders were collected from the different spots. The ecological parameters like evenness index, Margalef index, Shannon diversity index, Simpson index, Simpson diversity index and effective number of species were analysed to determine the population status of insects. The findings illustrated that the most abundant group of insects was Hymenoptera followed by Lepidoptera and Orthoptera, respectively. Notably, the differential biodiversity of insects and the variations in associated ecological parameters were observed due to the deviations in the environmental factors of four spots. Among four spots, spot 2 (Capital Public School) illustrated the highest Shannon diversity index (1.762), Simpson diversity index (0.829) and Margalef index (0.984). Thus, the assessed insect’s diversity and other intended ecological parameters can be beneficial to build the strategic frameworks for setting up the agro-based economic standards of a particular region.

Taxonomic Documentation and Statistical Analysis of Soil Mycoflora of Sanjay Gandhi National Park, Maharashtra, India

Aims: The present paper deals with documentation of diversity and analysis of ecological aspects of soil microfungal flora of Sanjay Gandhi National Park (SGNP).
 Study Design: The study area was divided into five zones, defined over span of three ranges and 10% peripheral area.
 Place and Duration of Study: SGNP, Maharashtra, India between September 2016 and September 2020.
 Methodology: A total of 43 soil samples were collected from 5 zones. Microscopic and molecular methods were used for identification of species. We examine dissimilarity in species composition by pairwise Jaccard Dissimilarity Index. We examine diversity of microfungi using diversity indices of Gini-Simpson’s and Shannon’s, true diversity (Shannon’s effective number of species) and equitability of species with Pielou’s evenness index.
 Results: The study resulted in a total of 77 isolates of 77 soil fungi obtained from 43 soil samples. A total of 36 species were documented under 15 genera. Aspergillus was dominant genus with 16 species, whereas Aspergillus niger was dominant species representing maximum 12 isolates. Pairwise Jaccard Dissimilarity Index was found to be above 66% in all cases, with only one species common in all the zones. In diversity indices, Gini-Simpson’s was 0.9347, and Shannon’s, was 3.1450. Pielou’s evenness index was 0.8776, causing true diversity, calculated as effective number of species (23), to be less than observed species richness (36).
 Conclusion: Thus, based on systematics and statistical analysis, it can be concluded that SGNP exhibits rich diversity of soil microfungi.

Effects of tree diversity on canopy space occupation vary with tree size and canopy space definition in a mature broad-leaved forest

• Tree diversity is positively related to canopy space occupation in manged forests. • The definition of the canopy space and tree size largely affects diversity-canopy space occupation relationships. • Diversity effects are strongest by considering the upper canopy space. • Novel conceptual framework to assess spatial crown complementarity. A more efficient use of limited canopy space and, thus, a higher canopy space occupation (CSO) in forests can result in an increased absorption of photosynthetically active radiation, which in turn can promote productivity. Although there is some evidence for a positive relationship between tree diversity (TD) and CSO, the generality of this hypothesis is still under debate. Here, we propose a conceptual framework that accounts for both the spatial complexity of canopy space and size-dependent interspecific tree interactions and tested it using mobile laser scanning data across larger spatial scales. We assessed the CSO at high resolution with two diversity indices, tree species richness (TSR) and the effective number of species (ENS) along a TSR gradient ranging from monocultures to 8-species mixtures in a mature and structurally complex mixed-species temperate forest. We found that the direction and strength of the TD-CSO relationship largely depended on the way how canopy space is defined and which tree size classes are considered to calculate TSR. Using an broad deliniation of canopy space no significant relationship between TD and CSO was evident. In contrast, when considering only the upper canopy space, a significant effect of TSR on CSO emerged. Importantly, the direction of this relationship was critically dependent on the tree size threshold underlying the TSR determination. For all trees with a diameter at breast height > 7 cm, we observed a significant negative relationship, while the opposite was the case when considering only large-sized trees. Our novel conceptual framework demonstrates that accurate estimation of canopy space complexity and tree size dependence is key to better understanding the processes underlying CSO. However, further information on diversity-canopy space occupation relationships from studies in different forests and forest types is needed.

How does variation in total and relative abundance contribute to gradients of species diversity?

Patterns of biodiversity provide insights into the processes that shape biological communities around the world. Variation in species diversity along biogeographical or ecological gradients, such as latitude or precipitation, can be attributed to variation in different components of biodiversity: changes in the total abundance (i.e., more‐individual effects) and changes in the regional species abundance distribution (SAD). Rarefaction curves can provide a tool to partition these sources of variation on diversity, but first must be converted to a common unit of measurement. Here, we partition species diversity gradients into components of the SAD and abundance using the effective number of species (ENS) transformation of the individual‐based rarefaction curve. Because the ENS curve is unconstrained by sample size, it can act as a standardized unit of measurement when comparing effect sizes among different components of biodiversity change. We illustrate the utility of the approach using two data sets spanning latitudinal diversity gradients in trees and marine reef fish and find contrasting results. Whereas the diversity gradient of fish was mostly associated with variation in abundance (86%), the tree diversity gradient was mostly associated with variation in the SAD (59%). These results suggest that local fish diversity may be limited by energy through the more‐individuals effect, while species pool effects are the larger determinant of tree diversity. We suggest that the framework of the ENS‐curve has the potential to quantify the underlying factors influencing most aspects of diversity change.

Diversity, population fluctuation and faunistic analysis of sharpshooters (hemiptera: Cicadellidae: Cicadellinae) in plum orchards in Videira, Santa Catarina, Brazil

Sharpshooters are known vectors of Plum Leaf Scald, caused by Xylella fastidiosa. The present study assessed diversity, population fluctuation and faunistic analysis in two plum orchards in Santa Catarina – Brazil, from January 2011 to December 2012. Traps were installed at 10 equidistant points in each orchard: two traps, high and low, at each sampling point. Cicadellini were the most abundant tribe, with 15 species, seven of them potential vectors (Bucephalogonia xanthophis, Dilobopterus costalimai, Hortensia similis, Macugonalia cavifrons, Macugonalia leucomelas, Pawiloma gratiosa, and Sibovia sagata) and a total of 759 specimens. In Proconiini, six species were captured, including two potential vectors (Homalodisca ignorata and Oncometopia facialis), and a total of 226 specimens. Dominant species were Erythrogonia dorsalis, M. cavifrons, O. fusca, B. xanthophis, and O. facialis. Constant species were E. dorsalis, M. cavifrons, S. sagata, O. facilis, and O. fusca. In Cicadellini, 104 specimens were caught on high traps (11 species) and 655 on low traps (15). In Proconiini, 59 specimens on high traps (6) and 167 on low traps (4). The composition and community diversity were distinct when comparing the sampled orchards, according to Shannon and Equitability Indexes, Effective Number of Species, and Hutcheson t-Test. Cicadellinae population peak was in April for 2011, 2012 altogether. Dominant species population peaks were in February (E. dorsalis), April (M. cavifrons), July (B. xanthophis), September (O. facialis), and October (O. fusca). Population fluctuation is likely affected by biotic and abiotic factors, especially human activity and plant phenology.

Visitantes florales en el cultivo de Phaseolus coccineus (Fabaceae) en el Altiplano de Puebla, México: importancia del manejo agrícola y color de flor

Antecedentes y Objetivos: Phaseolus coccineus es una planta alógama, con variación en color de la flor, que depende de polinizadores para su reproducción. La especie se cultiva bajo dos modalidades, una en la cual no se emplean agroquímicos para controlar arvenses y plagas (manejo tradicional) y otra en la que sí se usan (manejo tecnificado). No existen estudios que hayan evaluado la importancia del manejo agrícola y color de flor sobre los visitantes florales de esta especie, por lo que nuestro objetivo fue analizar cómo influyen estos factores en la diversidad y frecuencia de visitantes florales de P. coccineus. Métodos: Se estudiaron dos variedades de P. coccineus (de flor blanca y roja), cultivadas bajo dos sistemas de manejo diferentes. En el pico de floración, durante ocho días, se realizaron observaciones simultáneas, contabilizando el número de visitantes florales y de visitas. Se calculó la riqueza específica y los números de especies efectivas como medida de diversidad, se aplicaron pruebas de chi-cuadrada, se practicó un análisis de correspondencias y se construyeron gráficos de rango-abundancia. Resultados clave: Se registraron 42 morfoespecies, agrupadas en seis órdenes; predominaron Apis mellifera e Hylocharis leucotis. El número de visitas registradas fue de 1613 y 1105 en manejo tradicional de flores blancas y rojas, respectivamente, y de 1427 y 815 en el manejo tecnificado, existiendo diferencias estadísticas consistentes entre manejos, no así para color de flor. En flores blancas, el manejo tradicional fue dos veces más diverso que el tecnificado; en flores rojas, la diferencia fue de 1.26 veces. Conclusiones: La diversidad y frecuencia de visitantes florales de P. coccineus se ven favorecidas por el manejo agrícola tradicional, ello fundamenta la conveniencia de fomentar esta modalidad de cultivo. Bajo las condiciones estudiadas, el color de flor no influyó en la riqueza de especies, ni mostró tendencias definidas en la frecuencia de visitas.

Spatial Characterisation of Vegetation Diversity in Groundwater-Dependent Ecosystems Using In-Situ and Sentinel-2 MSI Satellite Data

Groundwater-Dependent Ecosystems (GDEs) are under threat from groundwater over-abstraction, which significantly impacts their conservation and sustainable management. Although the socio-economic significance of GDEs is understood, their ecosystem services and ecological significance (e.g., biodiversity hotspots) in arid environments remains understudied. Therefore, under the United Nations Sustainable Development Goal (SDG) 15, characterizing or identifying biodiversity hotspots in GDEs improves their management and conservation. In this study, we present the first attempt towards the spatial characterization of vegetation diversity in GDEs within the Khakea-Bray Transboundary Aquifer. Following the Spectral Variation Hypothesis (SVH), we used multispectral remotely sensed data (i.e., Sentinel-2 MSI) to characterize the vegetation diversity. This involved the use of the Rao’s Q to measure spectral diversity from several measures of spectral variation and validating the Rao’s Q using field-measured data on vegetation diversity (i.e., effective number of species). We observed that the Rao’s Q has the potential of spatially characterizing vegetation diversity of GDEs in the Khakea-Bray Transboundary Aquifer. Specifically, we discovered that the Rao’s Q was related to field-measured vegetation diversity (R2 = 0.61 and p = 0.00), and the coefficient of variation (CV) was the best measure to derive the Rao’s Q. Vegetation diversity was also used as a proxy for identifying priority conservation areas and biodiversity hotspots. Vegetation diversity was more concentrated around natural pans and along roads, fence lines, and rivers. In addition, vegetation diversity was observed to decrease with an increasing distance (>35 m) from natural pans and simulated an inverse piosphere (i.e., minimal utilization around the natural water pans). We provide baseline information necessary for identifying priority conservation areas within the Khakea-Bray Transboundary Aquifer. Furthermore, this work provides a pathway for resource managers to achieve SDG 15 as well as national and regional Aichi biodiversity targets.

Native tree species richness enhances matrix functionality for soil arthropods in tropical plantation landscapes: A case study from the Himalayas

AbstractDespite their distinctive role in regulating agroecosystems, soil fauna is largely excluded from conservation action. With increasing evidence supporting matrix functionality as critical for multiple species in agroecosystems, it is important that efforts meant to enhance biodiversity in managed systems be inclusive and effective for all species and not just charismatic fauna.Third party certifications are a popular mechanism for claiming pro‐conservation practises in tropical agricultural lands. Therefore, we asked whether voluntary practises codified by third party certifications of tropical tea plantations support soil biodiversity, and what factors explain soil arthropod abundance and richness in such certified and uncertified landscapes.We used pitfall trap data and soil samples across two seasons in large tea plantations, and small tea‐growing agroforestry farms in the Darjeeling Himalayas in India. Plantations certified and those not certified were selected for the study.Soil arthropod morphospecies abundance, richness and diversity were significantly higher in summer as opposed to winter. Contrary to our expectations, there was no significant difference in soil arthropod abundance, richness and diversity between uncertified small agroforestry farms and certified large monoculture plantations. Our analysis establishes tree species richness and season as the most important predictors of soil arthropod abundance, richness and effective number of species.We recommend that increased abundance and diversity of native trees in the tea matrix should be a crucial criterion for agroecosystem management. This would improve matrix functionality for species that are sensitive to management and reflect practises that enhance biodiversity.

A quick evaluation of ecological restoration based on arthropod communities and trophic guilds in an urban ecological preserve in Mexico City

BackgroundRestoration practices usually emphasize on the structural part of the biodiversity; also, most studies have focused on plants and very few have been conducted on arthropods and its function after restoration. The Pedregal de San Angel Ecological Reserve (PSAER) is a protected area immersed in Mexico City and it has been drastically affected by different anthropogenic disturbances. The aim of this study was to compare the relative diversity, richness, and abundance of species level identification, but also the composition through an analysis of ordination of taxonomic (species, family, and order level) and functional (trophic guild) traits of arthropods in three sites subjected to ecological restoration within the PSAER. Restored sites were also compared to conserved and disturbed sites, to evaluate whether restoration efforts are effective at the reserve.MethodsArthropods were sampled using pan traps during September 2013 in 11 sites (three restored, four conserved and four disturbed) inside the PSAER. All sampled species were taxonomically identified at species of morphospecies (inside a family) and assigned to a trophic guild. Differences in diversity, richness and abundance were evaluated through effective number of species, comparisons of Chao’s1 estimated richness and a non-parametric Kruskal–Wallis test, respectively. Both taxonomic and trophic guild composition were evaluated using a multivariate analysis and a post hoc test.ResultsWe found some differences in richness, abundance, and diversity between sites, but not a clear pattern of differentiation between restored to disturbed sites. The NMDS showed differences at species and order level, and with trophic guilds, among site types. Families were not useful to differentiate types of sites. Regarding guilds, predators were more abundant in conserved sites, while phytophagous insects were more abundant in disturbed sites.ConclusionsSpecies and order level were useful to identify differences in communities of arthropods in sites with different management. The trophic guild approach provides information about the functional state of the restored sites. Nevertheless, our quick evaluation shows that restoration efforts at PSAER have not been successful in differentiate restored to disturbed sites yet.

Impact of Grazing on Diversity of Semi-Arid Rangelands in Crete Island in the Context of Climatic Change.

The rangelands of Crete island (Greece) are typical Mediterranean habitats under high risk of degradation due to long-term grazing and harsh climatic conditions. We explored the effect of abiotic (climatic conditions, altitude) and biotic factors (long-term grazing by small ruminants) on the floristic composition and diversity of selected lowland (Pyrathi, Faistos) and highland (Vroulidia, Nida) rangelands. In each rangeland, the ground cover was measured, and the floristic composition was calculated in terms of five functional groups: grasses, legumes, forbs, phrygana, and shrubs. The aridity index, species turnover, species richness, Shannon entropy, and Gini–Simpson index (with the latter two converted to the effective number of species) were calculated. Our results reveal that highlands are characterized by the highest aridity index (wetter conditions). Lowland rangelands, compared to highland, exhibited a higher percentage contribution of grasses, legumes, and forbs, while species turnover decreased along the altitudinal gradient. The Shannon entropy index was correlated (a) positively with Gini–Simpson and mean annual temperature and (b) negatively with mean annual precipitation, aridity index, and altitude. Moreover, the Gini–Simpson index correlated positively with mean annual temperature and negatively with altitude. Our results could help to understand the effects of grazing on rangeland dynamics and sustainability in semi-arid regions in the context of climatic change.

Resiliency and Recovery of Aquatic Vegetation Following Scouring Floods in Two First-Magnitude Springs, Missouri, USA

This study quantifies the loss of vegetative cover in Alley and Big springs, Missouri, following a catastrophic, ‘100 year’ flood, and documents their subsequent recovery. Foliar cover of aquatic vegetation was measured in each spring along six transects, each having three sample cells (1 m2, N = 18). Species diversity analyses included taxa richness, Shannon’s diversity index, and Simpson’s diversity index, which were expressed as the effective number of species (S, He, and De). Species metrics were calculated as individual species frequency (ISF), percent foliar cover (PFC), and species importance value (SIV). Post-flood community diversity metrics (S, He, and De) for the springs were largely not significant for most measures (Epps–Singleton test p > 0.05). This suggests that they may not be sufficiently sensitive for detecting change in springs when the sample size is small. Bare substrate increased significantly at Big Spring post-flood (mean = 87.50%; Epps–Singleton test, p = 0.02), but not at Alley Spring (Epps–Singleton test, p = 0.42). Various alga taxa generally exhibited increased frequency and abundance following the flood, which is reflected in their overall higher SIVs. Most hydrophyte species at Alley Spring showed a marked decline compared to the pre-flood average, only to substantially increase in the last year of sampling, thus maintaining their approximate species important values relative to their pre-flood averages. Several hydrophyte species at Big Spring showed significant decreases (Epps–Singleton test p < 0.05) in their respective community metrics, and recovery had not returned to pre-flood levels on the last sampling date. This study showed that loss and recovery of aquatic vegetation in high-magnitude Ozark springs following flooding are a function of flood intensity as well as substrate size and retention, and proximity to the receiving stream.

Differences in canopy and understorey diversities after the eruptions of Mount Usu, northern Japan — Impacts of early forest management

Evaluating the effects of management on successional trajectories, plant composition, and diversity has been difficult due to the scarcity of long-term studies. This study examined the composition and diversity of species in natural and artificially regenerated forests at two eruption sites of Mount Usu, northern Japan, during 2015–2019, to compare the effects of active and passive management. The two sites are Yosomi, damaged by the 1910 eruptions, and the summit, damaged by the 1977–78 eruptions. Various natural and artificial forests developed at both sites, whose species composition was analyzed by non-metric multidimensional scaling to measure similarity between the forest types, and whose diversity was compared by the true diversity index, showing the effective number of species, from order 0 (presence-absence) to order 2 (weighted species) for two layers: the canopy (woody species with DBH > 3 cm) and understorey (< 2 m high plants). Canopy diversity was measured by stem density in five 10 m × 10 m plots in each forest type, and understory diversity was measured by shoot density in four 1 m × 1 m quadrats in each plot. The canopy and understorey species compositions were distinct between the forest types, but the canopy was more affected by management than the understorey, indicating that early forest management had long-term effects on species composition. Species composition of the plantations resembled those of the natural forests when the plantations had patchy spatial structure. The naturally regenerated forests showed the highest diversities at both eruption sites, while the plantations displayed low diversities, except in one case, when the plantation showed heterogeneous forest structure. The plantations changed their species composition slowly and did not transform into natural forests. In conclusion, we suggest using a patchy plantation design with some space between patches instead of dense planting, to create resilient, diverse, and native forests after disturbances.

Application of Shannon and Simpson Diversity Index to Study Plant biodiversity on Coastal Rocky Ridges Habitats with Reference to Census Data in the Ras El-Hekma and Omayed Area on the Western Coastal Region of Egypt

Biodiversity is a word recently introduced by experts in field of biology, and it is important for ecosystem health and productivity, biodiversity is one of the primary interests of ecologists, and the widely used diversity indices are Shannon’s and Simpson’s index. This study aims to characterize the plant communities and to identify and compare the plant species diversity in the Ras El-Hekma area and Omayed protectorate. The results of the application of the indices of plant biodiversity in both the Ras El-Hekma area and the Omayed protectorate showed that the value of the Shannon index ( H' ) 2.058 and 2. 322, the value of the Simpson index ( D ) 0.85 and 0.92, the value of the Evenness index ( E ) 0.89 and 0.96, the value of Effective Number of Species ( ENSSh , ENSSi ) 6.66, 7.83 and 12.5, 10.19 respectively. The results demonstrated the highest values were recorded in the community of Omayed protectorate compared with the Ras El-Hekma area. The results also revealed that ( H' ) in the two communities 2 ≥ H' &lt; 3. According to the criteria of diversity index, they were moderate diversity. As for the Evenness index (E), 0.75 &gt;E ≤ 1. According to the categorized of the Evenness index, both are stable community.Through the results, diversity indices indicate that there is a more diverse community in the Omayed protectorate compared with the Ras El-Hekma area. The reason may be due to the individuals in Omayed was more evenly distributed among the species than the individuals in Ras El-Hekma. Based on the interpretation of the criteria and categories of Shannon, Simpson, Evenness and Effective Number of Species indices, this meant that the Omayed had high environmental wellness and biodiversity level. Both indices are more reflective in nature and can predict the ecosystem health. Therefore, it may be good to have one of these biodiversity indices to be used for plant communities to understand the ecosystem healthiness in the habitats.

Widespread extinction debts and colonization credits in United States breeding bird communities

Species extinctions and colonizations in response to land cover change often occur with time lags rather than instantaneously, leading to extinction debts and colonization credits. These debts and credits can lead to erroneous predictions of future biodiversity. Recent attempts to measure debts and credits have been limited to small geographical areas and have not considered multiple land cover types, or the directionality of land cover change. Here we quantify the relative contribution of past and current landscapes on the current effective number of species of 2,880 US bird communities, explicitly measuring the response of biodiversity to increases and decreases in five land cover types. We find that the current effective number of species is still largely explained by the past landscape composition (legacy effect), depending on the type, magnitude and directionality of recent land cover change. This legacy effect leads to widespread extinction debts and colonization credits. Specifically, we reveal debts across 52% of the United States, particularly in recently urbanized areas, and colonization credits in the remaining 48%, which are primarily associated with grassland decrease. We conclude that biodiversity policy targets risk becoming rapidly obsolete unless past landscapes are considered and debts and credits accounted for.

The biological sink of atmospheric H2 is more sensitive to spatial variation of microbial diversity than N2O and CO2 emissions in a winter cover crop field trial

The integration of winter cover crop (WCC) in culture rotations promotes multiple ecosystem services, but concomitant microbial diversity and functioning responses in soil have received less attention. A field trial was established to test the hypothesis that enhanced crop diversity with the integration of WCC in a conventional maize-soy rotation promotes microbial diversity and the biological sink of H2 in soil, while reducing N2O emissions to the atmosphere. Vicia villosa (hairy vetch), Avena sativa (oat), and Raphanus sativus (Daikon radish) were cultivated alone or in combinations and flux measurements were performed throughout two subsequent growing seasons. Soil acted as a net sink for H2 and as a net source for CO2 and N2O. CO2 flux was the most sensitive to WCC whereas a significant spatial variation was observed for H2 flux with soil uptake rates observed in the most productive area two-fold greater than the baseline level. Sequencing and quantification of taxonomic and functional genes were integrated to explain variation in trace gas fluxes with compositional changes in soil microbial communities. Fungal communities were the most sensitive to WCC, but neither community abundance nor beta diversity were found to be indicative of fluxes. The alpha diversity of taxonomic and functional genes, expressed as the number of effective species, was integrated into composite variables extracted from multivariate analyses. Only the composite variable computed with the inverse Simpson's index displayed a reproducible pattern throughout both growing seasons, with functional genes and bacterial 16S rRNA gene defining the two most contrasting gradients. The composite variable was decoupled from WCC treatment and explained 19–20% spatial variation of H2 fluxes. The coupling of composite alpha diversity metrics derived from multiple genes with soil processes warrants further investigations to implement novel indicators of soil health in response to changing management practices at the local scale.