A key challenge in biodiversity is: How many species are there on earth? This issue is especially acute in poorly surveyed regions with high diversity, particularly Southeast Asia that also experiences many limitations such as lack of funds, documents and experts. To help meet this challenge, I have developed a five-tiered approach for diversity measurement of freshwater fish for use in Thailand. This is: (1) the creation of a newly updated species inventory that uses existing data; (2) exploration of the patterns of species richness, endemism, and uniqueness; (3) estimation of the total species richness; (4) investigation of patterns of rarity; and (5) integration of this knowledge into conservation practice. The system should be applicable to other regions and other taxa where a similar challenge exists. My work shows that eight hundred and seventy-two species in 17 orders, 55 families and 255 genera of freshwater fishes, accounting for roughly 10% of the world's freshwater fish diversity, have been reported for Thailand to date. This number was derived from information in the museum collections, literature and all other available sources, including reports written in Thai as well as in English. During this work I uncovered many gaps in biodiversity information, in terms of taxonomic and spatial records, though some families and basins are better represented than others. Taxonomic uncertainty also continues to be a challenge for taxonomists and users. The high diversity of freshwater fishes in Thailand is the result of both high alpha (α) diversity (diversity within a particular locality) and beta (β) diversity (diversity differences between localities). I concluded that the substantial beta diversity I detected is associated with the geographical separation of the six river basins in Thailand. For example, the species composition of freshwater fishes in the Salween Basin dramatically differs from all other basins of Thailand. In contrast, the Chao Phraya Basin and the Mekong Basin contain the greatest number of shared species. Approximately 55% of species have a wide distribution range (being reported from more than two basins), whereas 45% are highly restricted within a single basin. Analyses using species richness estimators suggest that the figure of 872 species is an underestimate and that there may be between 1000 and 1300 fish species in Thailand, in other words an increase of between 14.7% and 49.1% over the list I compiled (which is itself an increase of 52.2% over the last report in 1997). Freshwater fish have become increasingly vulnerable to anthropogenic activities. Of the 872 Thai fish species, 6.8% and 15.1% are globally and nationally threatened, respectively. Nonetheless, a striking feature of the database is that the conservation status of the vast majority of species has not so far been assessed, either globally or nationally. Scientists and policy makers will find these results useful in appreciating the magnitude of the tasks involved in surveying, describing and conserving the country's freshwater fish biota. My work highlights localities and taxa where conservation is a priority and is thus an important resource for policy makers and conservation planners concerned with the management of freshwater fish in Thailand.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The process of fragmentation of native environments has been increasing gradually in recent decades and forming small forest remnants in place of continuous and preserved forest. These effects on natural resources may cause changes in diversity and composition of various groups of animals, including butterflies. Among several factors responsible for the occurrence and distribution of species of guild fruit-feeding butterflies, the heterogeneity and structural complexity of the environment may be crucial to their survival. Thus, the present study sought to expand the knowledge on the guild of fruit-feeding butterflies for Médio Alto Uruguay region in Rio Grande do Sul, since the studies conducted until this moment have not used the same collection procedure. This study is also relevant for the conservation of the Deciduous Seasonal Forest, already significantly altered by human action. The objectives of this study were divided into two chapters. Chapter I aimed (i) to determine the diversity and composition of the guild fruit-feeding butterflies in two fragments of secondary formation of the Deciduous Seasonal Forest in environments in the edge and forest interior, (ii) to evaluate the edge effect regarding richness, composition and abundance of guild fruit-feeding butterflies, and (iii) to verify the influence of microclimate variables of temperature, relative humidity, wind speed, and brightness. Chapter II aimed to (i) sample the guild of fruit-feeding butterflies in an area of pasture Cynodon sp., and (ii) determine the population dynamics of this guild with respect to medium temperature and relative humidity of air and the total pluviosity of the site. From August 2012 to July 2013, fortnightly collections were performed using traps with attractive bait, modified of the model "Van Someren-Rydon", consisting of fermented banana with sugar cane juice. Four attractive traps were placed in the fragments in the edges and four traps were installed inside, distant 40 m from the edge of the fragment, suspended in tree branches. In the area of grazing of Cynodon sp., four traps were placed suspended on wooden supports. All 20 traps were placed 1.70 m above the ground. 2,077 specimens of fruit-feeding butterflies from 46 species and 4 subfamilies were captured. In the fragments analyzed, 2,003 specimens of fruit-feeding butterflies were identified. No significant difference between the edge and the interior environments of the forest fragments was observed when the richness of fruit-feeding butterfly species was compared. Microclimate variables of temperature, relative humidity, wind speed and brightness are significantly related to the distribution of species of fruit-feeding butterflies when canonical correspondence analysis was used in the interior and edge of fragments, with 10 and 30 years without exploration, respectively. The species, Yphthimoides affinis (Butler, 1867) found in one of the fragments is a new record for our state, Rio Grande do Sul. In the area of pasture of Cynodon sp., 74 specimens of fruit-feeding butterflies from 16 species as well as the highest richness of species was found in summer and spring seasons showing the seasonal variation of this guild in the area. / O processo de fragmentação de ambientes nativos vem aumentando gradativamente nas últimas décadas formando pequenos remanescentes florestais, no lugar da floresta contínua e preservada. Estes efeitos sobre os recursos naturais podem ocasionar mudanças na diversidade e composição de diversos grupos de animais, incluindo as borboletas. Dentre alguns fatores responsáveis pela ocorrência e distribuição das espécies de borboletas frugívoras, a heterogeneidade e a complexidade estrutural do ambiente, podem ser determinantes para a sua sobrevivência. Assim, o presente estudo, buscou ampliar o conhecimento sobre a guilda de borboletas frugívoras para a região do Médio Alto Uruguai do Rio Grande do Sul, uma vez que, os estudos realizados até então, não utilizaram o mesmo procedimento de coleta. Também é relevante este estudo, para a conservação da Floresta Estacional Decidual, já significativamente alterada pela ação antrópica. Os objetivos deste estudo foram separados em dois capítulos. Capítulo I: (a) verificar a diversidade e composição da guilda de borboletas frugívoras em dois fragmentos de formação secundária da Floresta Estacional Decidual, nos ambientes de borda e interior, (b) avaliar o efeito de borda, na riqueza, composição e abundância de borboletas frugívoras e (c) verificar a influência das variáveis microclimáticas de temperatura, umidade relativa do ar, velocidade do vento e luminosidade. Capítulo II: (a) amostrar a guilda de borboletas frugívoras em uma área de pastagem de Cynodon sp., e (b) verificar a flutuação populacional desta guilda com relação a temperatura e umidade relativa do ar médias e, a pluviosidade total do local. Para tanto, no período de agosto de 2012 a julho de 2013, foram realizadas coletas quinzenais utilizando-se armadilhas com isca atrativa, modificadas do modelo Van Someren-Rydon , constituída de banana fermentada com caldo de cana. Nos fragmentos, foram colocadas quatro armadilhas atrativas na borda e quatro armadilhas no interior, distantes 40 metros da borda do fragmento, suspensas em galhos de árvores. Na área de pastagem de Cynodon sp., foram colocadas quatro armadilhas suspensas em suportes de madeira. Todas as 20 armadilhas colocadas a 1,70m de altura do solo. Foram capturadas 2.077 espécimens de borboletas frugívoras, distribuídas em 46 espécies e quatro subfamílias. Nos fragmentos analisados, foram identificadas 2.003 espécimens de borboletas frugívoras. Não há diferença significativa entre os ambientes de borda e o interior dos fragmentos florestais quando a riqueza de espécies de borboletas frugívoras foi comparada. As variáveis microclimáticas de temperatura, umidade relativa do ar, velocidade do vento e luminosidade são significativamente relacionadas com a distribuição das espécies de borboletas frugívoras, através da análise de correspondência canônica, no interior e na borda dos fragmentos, com 10 anos e 30 anos sem exploração, respectivamente. A espécie, Yphthimoides affinis (Butler, 1867), encontrada no interior de um dos fragmentos, representa novo registro para o estado. Na área de pastagem de Cynodon sp., foram coletadas 74 espécimens de borboletas frugívoras distribuídas em 16 espécies e a maior riqueza de espécies foi encontrada nas estações de verão e primavera evidenciando a variação estacional desta guilda na área.

Les termites forment un groupe animal important en milieu tropical, où leur richesse spécifique est plus élevée que dans n’importe quel autre écosystème. Ils se nourrissent de matière organique végétale à différent état de décomposition, du bois dur à la matière organique minérale du le sol. Cette diversification du régime alimentaire ne se produit que chez les Termitidae, parfois appelés « termites supérieurs », alors que les autres familles se nourrissent exclusivement de bois ou d’herbe. Les termites humivores sont extrêmement abondants en Amérique du Sud et en Afrique tropicale, mais sont relativement peu étudiés par rapport aux termites xylophages. C’est particulièrement vrai pour le groupe Anoplotermes, qui représente le groupe de termites le moins bien connu. Ce travail vise à faire la lumière sur l’écologie et la diversité de ce groupe strictement humivore, et comprend les sections suivantes :(1) Des échantillonnages standardisés dans sept sites de Guyane Française ont révèle, avec quelques exceptions, que les termites xylophages sont relativement peu spécialisés à un site. Au contraire, les espèces du groupe Anoplotermes, ainsi que les termites humivores en général, sont spécialisés à un type de forêt. Cette spécialisation contribue plus que probablement à la diversification écologique, et donc, à une augmentation de la richesse spécifique des termites humivores. (2) En utilisant les ratios d’isotopiques δ13C et δ15N, nous avons aussi trouvé qu’il existe une spécialisation des espèces le long d’un gradient d’humification chez le groupe Anoplotermes, de l’interface entre le bois pourri et le sol au sol pauvre en matière organique. Donc, au moins deux facteurs favorisent la richesse spécifique du groupe Anoplotermes dans le sol, malgré le manque d’évidence pour une séparation spatiale et temporelle entre les espèces. Cette spécialisation spécifique réduit la compétition interspécifique aux espèces se nourrissant de matière organique au même état de décomposition. (3) Ce mécanisme n’est probablement pas restreint aux espèces du groupe Anoplotermes et le ratio isotopique δ15N varie considérablement entre les termites humivores de manière générale. Les termites humivores comptent des espèces avec des régimes alimentaires différents ne partageant pas toujours les mêmes niches écologiques. Cette diversification du régime alimentaire ne c’est pas produit de manière aléatoire durant l’évolution des termites et les espèces proches tendent à se nourrir du même substrat. (4) Au niveau intraspécifique, il semble que la compétition contraigne la dynamique des colonies. En effet, chez A. banksi, nous avons trouvé que les nids matures sont surdispersés. Les nouveaux nids se trouvent principalement à une certaine distance des nids établis, plus particulièrement dans les trous laissés par les nids morts. Si ce patron est le résultat d’une sélection des sites de nidification, ou plutôt d’une exclusion compétitive reste sujet à discussion, mais met néanmoins en évidence la présence de compétition chez les termites humivores du groupe Anoplotermes. (5) Au vu de la richesse spécifique locale du groupe Anoplotermes, le nombre d’espèces décrites reste remarquablement bas. Après inspection du matériel type, seuls 30 espèces du groupe se sont avérés valides en Amérique du Sud, alors que 80% des espèces que nous avons collectées sont nouvelles pour la science. Cette disproportion entre ce qui est connu et la diversité réelle du groupe, met en évidence le besoin de réaliser des études supplémentaires pour améliorer la connaissance de ce groupe peu connu, le groupe Anoplotermes. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

The assemblage structure, abundance, biomass, and vertical distribution of juvenile reef fishes in the offshore pelagic habitat of the northern Gulf of Mexico are described as part of the NOAA-supported Offshore Nekton Sampling and Analysis Program. The results presented here are from a 3-month, continuous sampling series in 2011 in which discrete depth strata from 0 to 1500 m were sampled using a 10-m2 MOCNESS midwater trawl. This is the first study to examine pelagic juvenile reef fish distributions across the entire oceanic northern Gulf of Mexico seaward of the continental shelf break after the Deepwater Horizon Oil Spill. During this series, 87,407 specimens were collected, of which 838 were reef fishes, representing seven orders, 30 families and 119 species. The faunal composition of pelagic juvenile reef fishes was diverse and well mixed, with no discernable spatial structure with respect to water masses and solar cycle. Seventy-nine percent of the pelagic juvenile reef fishes were collected in the epipelagic and the dominant families were Congridae, Carangidae, Tetraodontidae, and Acanthuridae. Species richness, biomass, and frequency of occurrence of pelagic juvenile reef fishes was greatest between 0-200 m and decreased with depth. Data from the assemblage structure, abundance, biomass, and vertical distribution of pelagic juvenile reef fishes collected from this cruise series will contribute to the lack of knowledge regarding the dispersal dynamics and coastal-connectivity of these fishes in the northern Gulf of Mexico.

Abstract Understanding of natural and human induced changes to freshwater biodiversity patterns is critical for efficiently conserving and managing these highly impacted ecosystems. In this doctoral thesis, I study the natural spatial and temporal variability of littoral macroinvertebrate communities, as well as aquatic biodiversity responses (of bryophytes, macroinvertebrates and diatoms) to human impact on forested headwater streams. I also study the temporal variability of natural and human-impacted stream communities. I show that littoral macroinvertebrate communities are most variable between individual samples and to some extent between littorals, and that the diversity patterns of rare and common littoral macroinvertebrates vary at different spatial scales. Temporal (interannual) variability is of minor importance, particularly for the core species of the community. For rare species, however, the temporal component was generally more important than spatial turnover. For headwater streams, I show that most taxonomic groups responded negatively to human impact on the adjacent riparian forest. Nevertheless, pristine riparian forest is not a sufficient surrogate for stream biodiversity as also streams with relatively disturbed riparian forests supported diverse benthic communities. A rapid classification method based on the physical structure of the stream channel and its riparian forest is able to identify the reference-state communities, as well as the most severely altered communities, but a reliable identification of the intermediately-disturbed sites would need more precise information about the key stressors of stream communities. I found that fine sediments originating from forest drainage were the main factor causing reduction of stream biodiversity. I also found that forestry impacted streams varied temporally more than pristine streams, emphasizing the importance of interannual sampling of impacted streams for a reliable status assessment. / Tiivistelmä Luonnollisen ja ihmisen aiheuttaman biodiversiteettivaihtelun ymmärtäminen hoito- ja suojelutoimissa on tärkeää pienvesien monimuotoisuuden turvaamiseksi. Tarkastelen väitöskirjassani järvien rantavyöhykkeen pohjaeläinten ajallista ja paikallista vaihtelua sekä latvapurojen eliöyhteisöjen (pohjaeläimet, sammalet, piilevät) vasteita ihmisen aiheuttamaan fysikaaliseen muutokseen rantametsässä ja purouomassa. Tarkastelen myös ajallisen vaihtelun eroja luonnontilaisten ja ihmisvaikutteisten latvapurojen eliöyhteisöjen välillä. Osoitan, että järven rantavyöhykkeen pohjaeläinyhteisöt vaihtelevat eniten yksittäisten näytteiden välillä ja pienessä määrin eri rantojen välillä, mutta ajallinen vaihtelu ei heikennä tulosten luotettavuutta muiden kuin harvinaisten lajien osalta yhteen vuoteen rajoittuvassa näytteenotossa. Purotutkimuksissa osoitan, että useiden vesieliöryhmien lajirunsaus muuttuu ihmisen aiheuttaman rantametsän muutoksen seurauksena, mutta luonnontilaista rantametsää ei silti voida pitää yksiselitteisesti myös puron suojelutason mittarina, koska se ei välttämättä turvaa eliöiden lajistollista eheyttä suhteessa alkuperäiseen alueelliseen lajistoon. Rantametsän ja uoman fysikaalisiin rakennepiirteisiin perustuvaa nopeaa luokittelumenetelmää voidaan käyttää eliöyhteisöltään monimuotoisimpien ja metsätalouden voimakkaimmin rasittamien purojen tunnistamisessa. Eliöyhteisöltään lievemmin muutettujen purojen luotettavaan erotteluun luokittelun pitäisi kuitenkin sisältää tarkempaa tietoa metsäojitusten aiheuttamasta liettymisestä, joka on tulosteni perusteella haitallisin metsätaloudesta johtuva puroyhteisöjä rasittava tekijä. Havaitsin myös metsätalouden rasittamien purojen tilanarvioinnin toistettavuuden olevan luonnontilaisia puroja heikompaa, joten metsätalouden rasittamien purojen pidempiaikainen seuraaminen tuntuu välttämättömältä luotettavien tilanarvioiden tuottamiseksi.

Orientador: Prof. Dr. Márcio de Souza Werneck / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Evolução e Diversidade, Santo André, 2017. / The variation in species richness has been explained by two major hypotheses: 1) Energy and Water dynamics, which explains the latitudinal gradient of biodiversity; and 2) Habitat Heterogeneity hypothesis, which shows that structurally more complex environments provide more niches by adding species diversity. Nevertheless, small scale studies have been pointed out the importance of the relationship between the number of species and the internal structure of the habitat and its disturbances. Due to the extensive effect of human disturbances on the biosphere, a more complex view of the relationships between human-modified tropical landscapes and their effects on all dimensions of biological diversity is necessary to ensure the success of biodiversity conservation and the management of the ecosystems functions. In this work, we analyzed the effect of anthropic land-use and natural coverage on the species richness of birds and mammals and mammalian guilds in the state of São Paulo, Brazil. We focused on three phases: 1) Energy - Water 2) Natural Coverage as an approximation to environment heterogeneity and 3) Anthropic land-use as an approximation to the effect of human disturbances. Using the Maximum Likelihood approach to select models, we selected the best explanatory variables for species richness to perform models to test the three hypotheses proposed to explain the richness of each group, the individual effect of each variable was also analyzed. Our database presented a great bias product of an unequal sampling effort along the grid that was attenuated by the selection of the best-surveyed cells through a complementarity analysis. We found that the anthropic land-use is the best explanatory hypothesis for birds and mammals richness. For mammalian guilds richness the Energy + Water hypothesis occupies the second place contrasting with the results widely presented in the literature, and revealing the importance of factors associated with human impact at regional scale. It emphasizes the positive relationship between richness and native vegetation cover, Conservation Units and Reforestation, and the negative relationship with the agricultural land-use. That reveals the importance of designing management policies that involve the conservation of remnants of native vegetation, the maintenance and creation of protected areas, and the focus of reforestation efforts for a more complex Forest Transition promoting the landscape connectivity. / A variação na riqueza de espécies tem sido explicada por duas grandes hipóteses, 1) a dinâmica da Energia e Água, que explica o gradiente latitudinal da biodiversidade e2) aHipótese da Heterogeneidade da Hábitat que expõe que os ambientes estruturalmente mais complexos fornecem maior quantidade de nichos acrescentando a diversidade de espécies. Porém, em menor escala muitos estúdios têm sinalado a importância da relação entre o número de espécies e a estrutura interna do hábitat e suas perturbações. Devido ao extenso efeito das perturbações humanas na biosfera faz-se necessário uma visão mais complexa das relações das paisagens tropicais modificadas pelo homem e seus efeitos sobre todas as dimensões da diversidade biológica, para garantir o sucesso da conservação da biodiversidade e o manejo das funciones dos ecossistemas. Nesse trabalho, nós analisamos o efeito do uso antrópico do soloe a cobertura natural sobre a riqueza de espécies de aves e mamíferos e a riqueza de guildas de mamíferos no estado de São Paulo, Brasil. Nós concentramo-nos em três hipóteses: 1) Energia ¿ Água 2) Cobertura Natural como uma aproximação à heterogeneidade do hábitat e 3) Uso Antrópico do Solo como uma aproximação ao efeito das perturbações humanas. Usando o enfoque de Máxima Verossimilhança para seleção de modelos, selecionamos as variáveis que melhor explicaram a riqueza, para logo testar as três hipóteses propostas para explicar a riqueza de cada grupo, também foi analisado o efeito individual de cada variável. Nossa base de dados apresentou um grande viés produto dum desigual esforço de amostragem ao longo do grid que foi atenuado pela seleção das células melhor amostradas a traves dum analise de complementariedade. Nós encontramos que o uso antrópico do solo é o melhor preditor para a riqueza de aves e mamíferos, mas para a riqueza de guildas de mamíferos a Energia + Água ocupa o segundo lugar, contrastando com os resultados amplamente apresentados na literatura, e revelando a importância dos fatores associados ao impacto humano a escala regional. Ressalta a relação positiva entre a riqueza e a cobertura de vegetação nativa, Unidades de Conservação e Reflorestamento, e a relação negativa com o uso agrícola do solo. Esso revela a importância de desenhar políticas de manejo que envolvam a conservação dos remanentes de vegetação nativa, o mantimento e criação de áreas protegidas, e focalização dos esforços de reflorestamento para uma Transição Florestal mais complexa em função da conectividade da paisagem.

No description available.

Thesis (M.Sc. Agriculture (Pasture Science)) -- University of Limpopo, 2021 / Savanna rangelands are ecosystems which are characterized by the co-existence of scattered trees and shrubs with a continuous grass layer. However, the grass and tree balance has been highly altered as a result of disturbances caused by bush encroachment. Encroaching woody species have been shown to decrease species richness and abundance of the seed bank and ground‐layer diversity. So far little is known on the effect of bush encroachment and soil depth on the soil seed bank diversity in savanna rangelands. The objectives of this mini-dissertation were to (1) determine the influence of soil depth on soil seed bank diversity in bush encroached savanna rangelands, and (2) determine the relationships between soil seed bank herbaceous vegetation and physicochemical properties in encroached rangeland. In order to address these objectives, a savanna rangeland was demarcated into two encroachment gradients spanning from open to encroached rangeland. Within each encroachment gradient, six plots of 10 m x 10 m were randomly selected, whereby soil sampling and herbaceous vegetation were carried out and determined. In each replicate plot per encroachment level, five soil samples were randomly collected at 0-10 and 10-20 cm depths. The number of seedlings of different species emerging from the soil samples was used as a measure of the number of viable seeds in the soil and the composition of the seed bank using the seedling emergence method. The total seed densities showed significant differences (P<0.05) in the 0-10 cm depth layer in the open rangeland and encroached rangeland. Bush encroachment significantly (P<0.05) decreased the seed density of perennial grasses, specifically in 0-10 cm depth layer. Further, species diversity increased with bush encroachment in the 10-20 cm depth layer. Menhinick’s richness index showed no significant difference in the open and encroached rangeland, while species evenness decreased in the 0-10 cm depth layer and increased at 10-20 cm depth.The study also revealed negative correlations between organic carbon, calcium, clay, silt and forbs while mean weight diameter (MWD), a measure of soil aggregate stability was positively correlated with forbs. The canonical correspondence analysis (CCA) showed that pH, phosphorus, potassium and calcium were positively correlated to Eragrostis curvula and magnesium was negatively correlated to Panicum maximum. In open rangeland, CCA revealed that clay content was negatively correlated with species evenness while xii magnesium was negatively correlated to the Shannon Weiner index. Further, silt content was positively correlated with species richness and evenness. In the encroached rangeland, the CCA showed a negative correlation between magnesium and the Shannon Weiner index. The Sørensen’s index between soil seed banks and aboveground vegetation was low with index values of 0.22 and 0.24 in open and encroached rangeland, respectively. / AgriSeta

Department of Ecology and Water Resources / MENVM

The aim of this work was to evaluate the limits of ranges of European land snail species along the north-south gradient. To work out the document it was necessary to prepare the set of digitalized maps, that enabled to create the database of ranges of the individual land snails species. Based on obtained data I tried to identify places where the northern and southern borders of species ranges are the most frequent. The landsnails' ranges are affected not only by particular life requirements of the individual species (potential limits), but also by other conditions, especially climatic, geographical and historical (truncated limits). In this work I focused on their differentiation. Above mentioned process also enabled me to track the north- south changes in species richness of the landsnails taking into consideration the truncated and potential limits. The most important natural barriers constraining that numerous of species cannot naturally widespread from the south to the north are the Scandinavian Mountains, the Alpes and the Carpathians and suprisingly also southern borders of german and polish lowlands. On the other hand, spreading of the species form the north to the south is limited only by the Alpes. I also tried to distinguish the group of species whose ranges are not influenced by these...