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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
381

Diversidade da ictio e carcinofauna do sistema estuarino de Santos-São Vicente (SP), Brasil : uma ferramenta para a avaliação da integridade ambiental /

Souza, Marcelo Ricardo de. January 2017 (has links)
Orientador: Marcelo Antonio Amaro Pinheiro / Banca: Maria Helena de Arruda Leme / Banca: Evandro Severino Rodrigues / Banca: Carolina Pacheco Bertozzi / Banca: Ursulla Pereira Souza / Resumo: Os estuários estão entre as áreas mais produtivas do planeta, sendo fundamentais ao ciclo de vida de muitas espécies e detentoras de elevado valor agregado. O Sistema Estuarino de Santos-São Vicente (SES) é conhecido por seu histórico de degradação ambiental, pela presença de uma expressiva área portuária, industrial, moradias ilegais (palafitas), além da descarga de esgoto e emprego para atividades pesqueiras. Apesar de sua intensa ocupação, poucos estudos têm sido efetuados sobre sua fauna aquática, em especial sobre a ictio e carcinofauna. Desta forma, a fauna de peixes e crustáceos foi avaliada com o intuito de inferir sobre o status de qualidade ambiental deste estuário. Foram realizadas coletas mensais por arrasto, durante dois anos, em nove áreas com diferentes pressões antropogênicas. Neste período, foram coletadas 93 espécies de peixes e 24 de crustáceos, com 12.170 e 2.164 indivíduos, respectivamente. Duas espécies de peixes apresentaram abundância muito superior às demais: Diapterus rhombeus (carapeba; Gerreidae) e Genidens genidens (bagre; Ariidae), representando 57% da abundância; o mesmo ocorreu com os crustáceos, no caso com apenas uma espécie, Callinectes danae (siri azul; Portunidae), que representou 58% da abundância destes artrópodos. Em relação a densidade dos peixes em sua maioria foram marinho-migrantes (57%), ocupando principalmente a área do alto estuário com grande abundância e baixa biomassa proporcional, em segundo lugar foram estuarino-residentes ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The estuaries are one of the most productive place on planet, essential to the life cycle of many species and high earned value. The Santos-São Vicente Estuary System (SES) is known for its history of environmental degradation, the presence of a significant harbor area, industrial, irregular dwellings (stilt houses), as well as the sewage discharge and employment for fishing activities. Despite its history, few studies about aquatic fauna have been made, especially about the ichthyo and carcinofauna. Because of that fishes and crustaceans was evaluated in order to analyse the environmental quality status of the estuary. Sampling was carried out for two years in 9 stations with differents anthropogenic pressures. A total of 12,170 fishes and 2,164 crustaceans from 93 and 24 taxas, respectively were captured. Two fishes, Diapterus rhombeus and Genidens genidens and one crustacean, Callinectes danae, showed high abundance (57% and 58% of total). For fishes, the major density was marinemigrants (57%), mainly on the high estuary with high abundance and low proportional biomass, the second guild were the estuarine-residents (31%), mostly on the main channels. The SES was classified as moderately impacted, the entrance of Harbor Channel showed the highest diversity in contrast of the high estuarine area. The hypothesis of local impacts over community was reject, the communities in general seem to be adapted by the existing pressures. The increase of anthropic pressure in the SES is a reality due to the port activities and human population density, for that reason an effective and long-term monitoring of aquatic fauna is recomended that continuously assesses the magnitude and variation (Spatial and Temporal) of anthropic impacts / Doutor
382

Levantamento da entomofauna de plantas medicinais, aromáticas e condimentares e desinfestação pelo processo de irradiação / Survey of insect fauna from plants medicinal, aromatic and seasoning and disinfestation the process of radiation

Fabrício Caldeira Reis 24 April 2013 (has links)
O presente trabalho teve como objetivo realizar o levantamento da entomofauna associada a plantas medicinais, aromáticas e condimentares desidratadas no comércio atacadista na cidade de São Paulo, empregar diferentes doses de radiação gama visando a desinfestação dos materiais e determina a dose letal de radiação gama de indivíduos adultos de Sphaericus gibboides. Foram coletados em 10 estabelecimentos no período de abril a maio de 2011 os materiais: Melissa officinalis L. (ervacidreira), Mentha piperita L. (hortelã), Ocimum basilicum L. (manjericão), Origanum vulgare L. (orégano), Rosmarinus officinalis L. (alecrim), Thymus vulgaris L. (tomilho), Senna alexandrina Mill (sene), Coriandrum sativum L. (coentro), Petroselinum crispum (Mill.) Fuss(salsa) e Pimpinella anisum L. (ervadoce), Baccharis trimera (Less.) DC. (carqueja), Matricaria chamomilla L. (= M. recutita L.) (camomila), Laurus nobilis L. (louro) (Lauraceae); Capsicum annuum L. (pápricadoce), Bixa orellana L. (colorífico) (Bixaceae); e Peumus boldus Molina (boldo). Na primeira triagem constatou-se que todos os materiais analisados não apresentaram presença de insetos adultos. Após o período de 45 dias foram encontrados 1838 insetos adultos, oriundos de ovos e larvas. Dos substratos analisados Matricaria recutita apresentou o maior índice de infestação, com 70,6 %. Pelmus boldus, Laurus nobilis, Matricaria recutita e Capsicum annuum, tiveram a maior diversidade de espécies. Baccharis strimera, Bixa orellana, Melissa officinalis, Origanum vulgares e Coriandrum sativum não apresentaram infestação. A espécie Lasioderma serricorne foi o inseto com maior número de indivíduos encontrados (936), maior porcentagem de infestação nos diferentes materiais (62,5 %) e maior ocorrência (68,75 %) nos materiais (M. piperita, S. alexandrina, P. anisum, M. chamomilla, P. crispum, L. nobilis, C. sativum, C. annuum, O. basilicum, P. boldus e T. vulgaris). Os seguintes materiais foram selecionados para os ensaios de desinfestação pelo processo de irradiação: Bixa orellana, Capsicum annuum, Cassia angustifolia, Coriandrum sativum, Mentha piperita, Petrosolium sativum, Matricaria recutita. Os materiais foram infestados com adultos de L. serricorne e Sphaericus gibboides, divididos em 5 parcelas de 30g com 20 indivíduos cada. Utilizando o Irradiador Multiprpósito cobalto-60 com taxa de dose no período dos ensaios de 6 kGy/h, as parcelas foram submetidas a doses crescentes de radiação gama de 0 (grupo controle); 0,25; 0,50; 0,75; 1,00; 1,25; 1,50; 1,75 e 2,00 kGy. A determinação da dose letal para adultos de Sphaericus gibboides, procedeu-se irradiando 4 repetições por tratamento contendo 25 indivíduos cada. As doses utilizadas foram: 2,4; 2,2; 2,0; 1,8; 1,6; 1,4; 1,2; 1,0; 0,8; 0,6 kGy. A menor dose para a não emergência de adultos de L. serricorne e S. gibboides em todos os materiais analisados foi a de 0,25 kGy. Não foi observada a presença de adultos nas demais doses crescentes. Foi observado que os materiais adquiridos no comércio apresentaram diferentes porcentagens de infestação justificando assim a aplicação de métodos de controle. A utilização do Irradiador Multipropósito Cobalto-60 com taxa de dose de 6 kGy/h foi eficiente no controle de L. serricorne e S. gibboides na dose de 0,25 kGy. A dose de 2,2 kGy atingiu 100% letalidade em indivíduos adultos de S. gibboides. / The present study aimed to survey the insect fauna associated with medicinal plants, aromatic dehydrated and seasoning trade in São Paulo city, using different doses of gamma radiation with the aim of disinfestation of the material and determine the lethal dose of gamma radiation on Sphaericus gibboides. From April to May 2011 were collected in 10 establishments the following sample materials: Melissa officinalis L. (Lemongrass), Mentha piperita L. (Mint), Ocimum basilicum L. (Basil), Origanum vulgare L. (Oregano), Rosmarinus officinalis L. (Rosemary), Thymus vulgaris L. (Thyme), Senna alexandrina Mill (senna), Coriandrum sativum L. (Coriander), Petroselinum crispum (Mill.) Fuss (salsa) and Pimpinella anisum L. (Fennel), Baccharis trimera (Less.) DC. (Gorse), Chamomilla recutita L. (= M. recutita L.) (chamomile), Laurus nobilis L. (Blonde) (Lauraceae); Capsicum annuum L. (Sweet paprika), Bixa orellana L. (Spice) (Bixaceae) and Peumus boldus Molina (Boldo). The first screening showed that all the tested materials did not show the presence of adult insects. After 45 days 940 adult insects were found and larvae from eggs. The substrates analyzed Chamomilla recutita showed the highest rate of infestation, with 70,6%. Pelmus boldus, Laurus nobilis, Chamomilla recutita and Capsicum annuum, had the highest species diversity. Baccharis trimera, Bixa orellana, Melissa officinalis, Origanum vulgare and Coriandrum sativum showed no infestation. The species was Lasioderma serricorne the insect with the largest number of individuals found (936), higher percentage of infestation in different materials (62.5%) and lots, and highest occurrence (68,75%) materials (M. piperita, S. alexandrian, P. anisum, Chamomilla recutita, P. crispum, L. nobilis, C. sativum, C. annuum, O. basilicum, P. boldus and T. vulgaris). The following materials were selected for testing disinfestation by irradiation process: Bixa orellana, Capsicum annuum, Cassia angustifolia, Coriandrum sativum, Mentha piperita, Petrosolium sativum, Chamomilla recutita. The materials were infested with adults of L. serricorne and S. gibboides, divided into 5 portions of 30g with 20 individuals each. Using Radiator Multiprpósito Cobalt-60 dose rate during the tests of 6 kGy/h, the plots were subjected to increasing doses of gamma radiation of 0 (control), 0,25; 0,50; 0,75; 1,00; 1,25; 1,50; 1,75 and 2,00 kGy. The determination of the lethal dose for adults S. gibboides, proceeded radiating 4 replicates per treatment each containing 25 individuals. The doses used were: 3,0; 2,8; 2,6; 2,4; 2,2; 2,0; 1,8; 1,6; 1,4; 1,2; 1,0; 0,8; 0,6 kGy. The lowest dose at no emergence of adult L. serricorne and S. gibboides in all materials tested was to 0,25 kGy. We did not observe the presence of other adults in increasing doses. It was observed that the materials acquired in trade showed different percentages of infestation thus justifying the application of control methods. Using Radiator Multiprpósito Cobalt-60 with dose rate of 6 kGy was effective in controlling L. serricorne and S. gibboides at a dose of 0,25 kGy. The dose of 2,2 kGy reached 100% mortality for adults of S. gibboides.
383

Helmintofauna de Columba livia (Aves, Columbidae), no munic?pio de Juiz de Fora, Minas Gerais, Brasil: aspectos da ecologia, morfologia e sistem?tica

Paula, Sthefane D'?vila de Oliveira e 15 February 2007 (has links)
Made available in DSpace on 2016-04-28T20:16:22Z (GMT). No. of bitstreams: 1 2007- Sthefane D avila de Oliveira e Paula-01.pdf: 3469002 bytes, checksum: 6411676587b6fa03e9508964399be8e0 (MD5) Previous issue date: 2007-02-15 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The aim of the present study was to obtain data on helminth fauna in Columba livia, in municipality of Juiz de Fora, Minas Gerais, Brasil; to describe the structure of the helminth infracommunities present in this host and to clarify questions concerning morphology, sistematics and ecology of some of the component species. The helminthological study of 35 hosts revealed the presence of two digenetic trematodes, Tanaisia (Paratanaisia) bragai (prevalence 51.42%, mean intensity 288.8 ? 403.86 and mean abundance 148 ? 320.9) and T. inopina (prevalence 2.85% and mean abundance 0.68 ? 4.05); five cestodes, Raillietina allomyodes (prevalence 34.28%, mean intensity 6.66 ? 9.14 and mean abundance 2.28 ? 6.11), Raillietina sp. (prevalence 37.14%, mean intensity 9 ? 10.68 and mean abundance 3.34 ? 7.7), Skrjabinia bonini (prevalence 20%, mean intensity 2.14 ? 1.21 and mean abundance 0.42 ? 1), Skrjabinia sp.( prevalence 5.7%, mean intensity 6 ? 7 and mean abundance 0.34 ? 7) and Fuhrmanneta sp. (prevalence 2.85% and mean abundance 0.028 ? 0.16) and four nematodes, Baruscapillaria obsignata (prevalence 51.42%, mean intensity 29.72 ? 44.2 and mean abundance 15.28 ? 34.7); Ascaridia columbae (prevalence 51.42%, mean intensity 60.55 ? 79.88 and mean abundance 31.14 ? 64.2); Tetrameres fissipina (prevalence 14.28%, mean intensity 346.3 ? 504.4 and mean abundance 49.42 ? 212.1) and Synhmanthus (Dyspharynx) nasuta (prevalence 2.85% and mean abundance 0.028 ? 0.16). Among the examined hosts, 97.2 % were found parasitized by at least one helminth species. In accordance with the prevalence of each species T. bragai, A. columbae and B. obsignata were considered secondary species and T. inopina, T. fissipina, S. nasuta, S. bonini, Skrjabinia sp., R. allomyodes, Raillietina sp. and Fuhrmanneta sp. were considered satellite species. All the species exhibited aggregate distributions, wich is the most common distribution pattern in helminth populations. Taxonomic and ecologic aspects of B. obsignata infrapopulations were analised and the results are discussed in terms of possible factors influencing the processes that lead to niche restriction and biased sex ratios in parasite infrapopulations. Additionaly, studies on morphology and sistematics of some component species were performed. Tanaisia (Paratanaisia) bragai and T. inopina specimens were analised by means of confocal laser scanning microscopy. Two new species of Raillietina and Skrjabinia were described and the sequences of the ITS2 ribossomal DNA of these species were determined and combined with other available Raillietina and Skrjabinia sequences in GenBank, in order to perform a phylogenetic study. / O conhecimento da helmintofauna de Columba livia, no Brasil, teve in?cio com as investiga??es a respeito do parasitismo em animais dom?sticos. Esses he lmintos foram relativamente bem estudados, sob o aspecto faun?stico. No entanto, existem lacunas no conhecimento da morfologia, sistem?tica e ecologia das esp?cies. O conhecimento sobre a morfologia e, consequentemente, os caracteres utilizados na sistem?tica, se restringem quase totalmente `as informa??es que a microscopia de luz pode fornecer. N?o existem estudos sobre a ecologia das infracomunidades desses parasitos, no Brasil. Al?m disso, as rela??es entre algumas esp?cies ainda s?o incertas, sendo necess?ria a revis?o da posi??o taxon?mica e filogen?tica desses helmintos. O presente trabalho teve como objetivos gerais: 1- conhecer a helmintofauna de C. livia, no munic?pio de Juiz de Fora, Minas Gerais; 2- determinar a estrutura da comunidade desses helmintos; 3- elucidar quest?es relativas ? morfologia, sistem?tica e ecologia de algumas das esp?cies componentes dessa comunidade. Para este fim, foram necropsiadas 35 aves e os helmintos coletados foram processados segundo as t?cnicas helmintol?gicas conve ncionais e quantificados. Foram calculados o ?ndice de dispers?o, para determinar o padr?o de distribui??o das infrapopula??es; o ?ndice de concentra??o de domin?ncia de Simpson, para avaliar a presen?a de esp?cie dominante na estrutura da comunidade e o ?ndice de Brillouin (H), para determinar a diversidade parasit?ria da comunidade. O estudo helmintol?gico revelou a presen?a de duas esp?cies de digen?ticos, Tanaisia (Paratanaisia) bragai (preval?ncia 51.42%, intensidade m?dia 288.8 ? 403.86 e abund?ncia m?dia 148 ? 320.9) e T. inopina (preval?ncia 2.85% e abund?ncia m?dia 0.68 ? 4.05); cinco esp?cies de cest?ides, Raillietina allomyodes (preval?ncia 34.28%, intensidade m?dia 6.66 ? 9.14 e abund?ncia m?dia 2.28 ? 6.11), Raillietina sp. (preval?ncia 37.14%, intensidade m?dia 9 ? 10.68 e abund?ncia m?dia 3.34 ? 7.7), Skrjabinia bonini (preval?ncia 20%, intensidade m?dia 2.14? 1.21 e abund?ncia m?dia 0.42 ? 1), Skrjabinia sp. (preval?ncia 5.7%, intensidade m?dia 6 ? 7 e abund?ncia m?dia 0.34 ? 7) e Fuhrmanneta sp. (preval?ncia 2.85% e abund?ncia m?dia 0.028 ? 0.16) e quatro esp?cies de nemat?ides, Baruscapillaria obsignata (preval?ncia 51.42%, intensidade m?dia 29.72 ? 44.2 e abund?ncia m?dia 15.28 ? 34.7); Ascaridia columbae (preval?ncia 51.42%, intensidade m?dia 60.55 ? 79.88 e abund?ncia m?dia 31.14 ? 64.2); Tetrameres fissipina (preval?ncia 14.28%, intensidade m?dia 346.3 ? 504.4 e abund?ncia m?dia 49.42 ? 212.1) e Synhimanthus (Dyspharynx) nasuta (preval?ncia 2.85% e abund?ncia m?dia 0.028 ? 0.16). Aspectos da taxon?mia e ecologia das infrapopula??es de B. obsignata foram abordados e os resultados discutidos em termos dos poss?veis fatores com influ?ncia nos processos que levam `a restri??o de nicho e raz?es sexuais enviezadas. Adicionalmente, foram realizados estudos sobre a morfologia e sitem?tica de algumas das esp?cies componentes. Aspectos da morfologia de Tanaisia (Paratanaisia) bragai e T. inopina, foram elucidados utilizando-se como ferramenta a microscopia de varredura a laser confocal. Um estudo filogen?tico de esp?cies dos g?neros Raillietina e Skrjabinia, foi realizado atrav?s da an?lise de seq??ncias da regi?o espa?adora transcrita interna 2 (ITS2) do DNA ribossomal e duas esp?cies novas foram descritas.
384

Variabilidade Espacial de Atributos Qu?micos, F?sicos e Biol?gicos em Vo?oroca Revegetada no Munic?pio de Pinheiral - RJ / Spatial Variability of Soil Chemical, Physical and Biological Properties in a Gully Erosion Revegetated in the Municipatily of Pinheiral - RJ

Rodrigues, Khalil de Menezes 25 February 2010 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-06-02T16:01:37Z No. of bitstreams: 1 Khalil de Menezes Rodrigues.pdf: 1672229 bytes, checksum: c8a308c58b7c1273496289e24d6e0e4f (MD5) / Made available in DSpace on 2016-06-02T16:01:37Z (GMT). No. of bitstreams: 1 Khalil de Menezes Rodrigues.pdf: 1672229 bytes, checksum: c8a308c58b7c1273496289e24d6e0e4f (MD5) Previous issue date: 2010-02-25 / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / The objective of this project was to study the spatial variability of soil physical and chemical attributes and soil fauna of a revegetated gully erosion area in Pinheiral municipality, Rio de Janeiro State. The gully area was vegetated using legume trees inoculated with specific N2- fixing bacteria and arbuscular mycorrhizal fungi (AMF) in 2004. To take the data and geostatistical analysis a regular grid of 5 x 5 m, with a total of 92 points, was defined. Soil samples were collected at the 0-10 cm depth and the following variables were analyzed: Al, pH, Ca, Mg, Ca+Mg, P, K, organic C, granulometry, soil moisture, and soil fauna (using pitfall traps). The software GEOEST was used for data analysis and definition of semivariograms to verify the spatial dependency and to choose the statistical model, using cross validation. Geostatistical analyses applied in the mapping of the spatial variability of soil chemical, physical and biological attributes of the gully area was a useful tool in the degraded gully to identify the areas, and the soil management for application of lime, fertilizers and planting the tree seedlings. The soil sampling for environmental monitoring of gully erosion areas should consider, at least, the slope position internally and externally in the gully area, dividing it in upper, medium and lower positions. Spatial dependence was observed in all soil chemical and physical attributes, and only 11 of the soil fauna groups out of 31 evaluated presented spatial dependence. The random sampling without considering the range value may result in wrong interpretation of data. The differences in soil organic C between the gully inner and outer sections clearly proves how difficult is to return the soil organic matter to the original levels, one it is lost in the soil. The analysis of data showed that altitude, soil moisture, sand and silt content, Ca+Mg, organic C, amounts of Coleoptera and Poduromorpha, had a strong spatial dependence. On the other hand, clay content, pH, Al, Ca, Mg, P, Acari, Entomobryomorpha, Collembola, fauna total, Hymenoptera, Formicidae, Shannon index, and Isoptera, presented a moderate degree of spatial dependence, and the richness index and Diptera had a weak degree of spatial dependence. / O objetivo do trabalho foi estudar a variabilidade espacial de atributos qu?micos e f?sicos do solo e a fauna ep?gea em uma vo?oroca revegetada no munic?pio de Pinheiral. Na revegeta??o da vo?oroca foram plantadas leguminosas arb?reas inoculadas com bact?rias fixadoras de N2 espec?ficas e fungos micorr?zicos arbusculares (FMA) no ano de 2004. Para a coleta de dados e para permitir a an?lise geoestat?stica foi instalada uma grade com espa?amento regular de 5 x 5 m, num total de 92 pontos. As amostras de solo foram coletadas na profundidade de 0-10 cm e as seguintes vari?veis foram analisadas: Al, pH, Ca, Mg, Ca + Mg, P, K, Carbono org?nico, granulometria, umidade gravim?trica e a fauna do solo ep?gea (usando pitfall). Na an?lise de dados utilizou-se o programa GEOEST que ? um pacote de programas geoestat?sticos onde foram constru?dos semivariogramas para verificar a depend?ncia espacial e a escolha do modelo estat?stico por valida??o cruzada. A an?lise geoestat?stica no mapeamento da variabilidade espacial dos atributos qu?micos, f?sicos e biol?gicos em vo?orocas mostrou ser uma ferramenta muito ?til neste ambiente degradado e na identifica??o das ?reas, podendo manejar o solo com o uso mais eficiente de adubos e corretivos para o plantio de novas mudas. Amostragem de monitoramento ambiental em ?reas de vo?oroca deve considerar, no m?nimo, a posi??o do relevo em parte interna e externa e a posi??o do vo?orocamento em ter?o superior, ter?o m?dio e ter?o inferior. A depend?ncia espacial foi observada em todos os atributos qu?micos e f?sicos e apenas 11 grupos da fauna do solo dos 31 coletados apresentaram depend?ncia espacial. Amostragem ao acaso em vo?orocas pode resultar em interpreta??o err?nea dos dados. A diferencia??o dos teores de carbono org?nico encontrados na parte interna e externa da vo?oroca deixa clara a dificuldade de se retornar a mat?ria org?nica do solo ap?s sua perda. Na an?lise do grau de depend?ncia espacial, a altitude, umidade gravim?trica, areia, silte, Ca+Mg, Corg, Coleoptera e Poduromorpha apresentaram grau forte. Por outro lado, o teor de argila, pH, Al, Ca, Mg, P, Acari, Entomobryomorpha, Collembola, total da fauna, Hymenoptera, Formicidae, o somat?rio de outros grupos, ?ndice de Shannon e Isoptera apresentaram grau moderado, enquanto a Riqueza e Diptera mostraram grau fraco.
385

Régimen jurídico de conservación de la biodiversidad en Chile

Soto Oyarzún, Lorenzo Iván 07 March 2014 (has links)
No description available.
386

Effects of Host Plant Patch Size and Surrounding Plant Type on Insect Population Dynamics

Maguire, Lynn A. 01 May 1980 (has links)
The purpose of the present study was to investigate how plant spatial patterns and insect behavior interact to influence the population dynamics of insects using the plants. The study included three phases: l) field experiments using collards (Brassica oleracea) and the crucifer insect fauna; 2) simulation models representing the population dynamics of an insect herbivore as functions of insect dispersal behavior and host plant patch size; and 3) model-field syntheses integrating model predictions and field variability estimates to choose an appropriate spatial scale for future field experiments or applications. In field experiments on surrounding plant type, collards were planted with 1) other collards; 2) collards treated with a systemic insecticide; 3) broccoli, a related host; and 4) tomatoes, an unrelated host whose odor may repel crucifer pests. In three such experiments, eggs and larvae of the imported cabbageworm (Pieris rapae (L.)) were most abundant an collards surrounded by tomatoes. These results were contrary to those from previous experiments with other crucifer pests, but can perhaps be explained by P. rapae's preference for ovipositing on isolated host plants. In three patch size experiments, P. rapae eggs and larvae were more abundant on collards in small patches; in one of these experiments, the diamondback moth (Plutella xylostella (Linn.)) was more abundant in large patches. The results for P. rapae were consistent with previous studies showing more oviposition on plants in smaller patches and on plants at the edge of a patch. The simulation models predicted mean level and variability of an insect herbivore population based on interactions between insect behavior and host plant patch size. Features of insect behavior modeled were: 1) an inverse relationship between distance and dispersal; 2) preferences for host vs. nonhost plants, which differ for generalist and for specialist herbivores; and 3) preference of specialists for larger areas of host plants. Aspects of plant pattern studied were size and number of host plant patches in a background of nonhost vegetation. Constant, exponential and logistic growth of insect populations in the nonhost background and in the host patches were used. The models were designed to provide a theoretical framework for studying interactions between insect behavior and plant pattern, not to duplicate the dynamics of the field system. However, for the model-field syntheses, parameters of one model were fit to field data to establish a correspondence between expected differences in population levels predicted by the model and variability estimates obtained in the field experiments. The fitted model was used to construct a graph of differences in population levels versus patch size. Field variability estimates were used to calculate the least difference in population levels, for a given number of replicates and subsamples, that could be detected in field experiments. The least difference was compared with the differences predicted b y the fitted model to determine what patch sizes will produce significant effects of patch size on insect populations. This method was used to assess feasibility of future field experiments and to select appropriate patch sizes. The method can also be used to evaluate crop field size in agroecosystems as a component of pest management.
387

Prospección fitosanitaria en un bosque puro de ciprés de la cordillera (Austrocedrus chilensis) en San Gabriel, Comuna de San José de Maipo, Región Metropolitana

Jorquera Olave, Víctor January 2012 (has links)
Memoria para optar al Título Profesional de Ingeniero Forestal / Este estudio entrega un registro de los principales problemas sanitarios, evaluación física del daño y sus principales agentes causales, de un bosque puro de ciprés de la cordillera, Austrocedrus chilensis (D. Don) Pic. Serm. et Bizarri (Cupressaceae), en San Gabriel, Región Metropolitana; además de identificar la fauna entomológica asociada y entregar propuestas preliminares de medidas silviculturales. El área de estudio fue un bosque puro, ralo y de sitio xérico, bajo la influencia de diversos factores de origen natural y antrópico. Se evaluaron síntomas, signos y daños en la población natural de A. chilensis, mediante un muestreo de 50 árboles, bajo la metodología de líneas de muestreo de 10 árboles cada una, con 5 repeticiones, y una intensidad de 5 cada 1.000 árboles. Para la colecta e identificación de los insectos se utilizaron trampas entomológicas y se hicieron prospecciones al azar en enero y febrero de 2011. También se colectaron conos con distinta orientación en copas de árboles al azar a alturas variables, para el análisis de conos y semillas. En general, los árboles presentaron un buen estado de vigor y los síntomas generales más importantes fueron daño mecánico y espiralamiento. En las ramas el problema fitosanitario más importante fue la escoba de bruja, mientras que en el follaje fue una clorosis y defoliación leve, y en el fuste la presencia de cancros y resinación. Se registró 49% de consumo de las semillas maduras, probablemente por larvas de Nanodacna austrocedrella (Laundry & Adamski) (Lepidoptera: Agonoxenidae); además se identificó un total de 35 especies de insectos asociados a bosques puros de ciprés de la cordillera. Debido a que el principal problema del bosque en San Gabriel es la escasa regeneración, como medidas silviculturales se propone aumentar la presencia de especies arbustivas nativas, instalar o reparar cercos de los límites del predio, manejo arbustivo, y el control de la población del microlepidóptero que consume las semillas de A. chilensis. Palabras clave: Austrocedrus chilensis, insectos, síntomas d
388

Early developments in the literature of Australian natural history : together with a select bibliography of Australian natural history writing, printed in English, from 1697 to the present

Drayson, Nick, English, Australian Defence Force Academy, UNSW January 1997 (has links)
Early nineteenth-century Eurocentric perceptions of natural history led to the flora and fauna of Australia being thought of as deficient and inferior compared with those of other lands. By the 1820s, Australia had become known as ???the land of contrarieties???. This, and Eurocentric attitudes to nature in general, influenced the expectations and perceptions of immigrants throughout the century. Yet at the same time there was developing an aesthetic appreciation of the natural history of Australia. This thesis examines the tension between these two perceptions in the popular natural history writing of the nineteenth century, mainly through the writing of five authors ??? George Bennett (1804-1893), Louisa Anne Meredith (1812-1895), Samuel Hannaford (1937-1874), Horace Wheelwright (1815-1865) and Donald Macdonald (1859?-1932). George Bennett was a scientist, who saw Australian plants and animals more as scientific specimens than objects of beauty. Louisa Meredith perceived them in the familiar language of English romantic poetry. Samuel Hannaford used another language, that of popular British natural history writers of the mid-nineteenth century. To Horace Wheelwright, Australian animals were equally valuable to the sportsman???s gun as to the naturalist???s pen. Donald Macdonald was the only one of these major writers to have been born in Australia. Although proud of his British heritage, he rejoiced in the beauty of his native land. His writing demonstrates his joy, and his novel attitude to Australian natural history continued and developed in the present century.
389

The Role of Epibenthic and Planktonic Fauna in Subtropical Prawn Grow Out Ponds

Coman, Francis Edmund, n/a January 2003 (has links)
The assemblage composition, biomass and dynamics of zooplankton and epibenthos were examined in a commercial prawn pond in southeast Queensland over two seasons. Physico-chemical characteristics of the pond water were measured concurrently. Numbers and biomass of zooplankton in the surface tows (140 micrometre mesh) varied from 8 ind. L-1 (44 micrograms L-1) to 112 ind. L-1 (324 micrograms L-1) in the first season, with peaks in biomass corresponding to peaks in numbers. In the second season the zooplankton numbers varied from 12 to 590 ind. L-1, but peaks in numbers did not correspond with peaks in biomass, which varied from 28 to 465 micrograms L-1. This was due to differences in the size of the dominant taxa across the season. Although this occurred in both seasons, the effect on biomass was more pronounced in the second season. In both seasons, immediately after the ponds were stocked with prawn postlarvae there was a rapid decline in zooplankton numbers, particularly of the dominant larger copepods. This was probably due to predation by the postlarvae. Subsequent peaks in zooplankton numbers were principally due to barnacle nauplii. The largest peaks in zooplankton numbers occurred before stocking in the first season, but the largest peaks were in the middle of the second season. While changes in abundance and biomass of the zooplankton assemblage were not correlated with physico-chemical characteristics in the first season, there were correlations between zooplankton numbers and temperature, dissolved oxygen, pH and secchi disk readings in the second season. No correlations were found with zooplankton biomass and physico-chemical characteristics in the second season. The correlations in the second season were mainly due to the high prevalence of barnacle nauplii through the middle part of the season, and may reflect suitable conditions for barnacle reproduction. Epibenthic faunal abundance in the beam trawls (1 mm mesh) peaked at 14 ind. m-2 and 7 ind. m-2 in the first and second seasons respectively and the biomasses at 0.8 g m-2 and 0.7 g m-2. Peaks in abundance of epibenthos did not correspond to peaks in biomass. This was due to large differences in the size of the taxa across the seasons. Sergestids (Acetes sibogae) and amphipods were the most abundant taxa in beam trawl samples. Amphipods were only abundant in the first season, with their numbers increasing towards the end of the grow out period. Acetes were abundant in both seasons, but were dominant in the second season. Correlations between physico-chemical parameters and epibenthos numbers were found to be strongly influenced by the dominant taxa in each season. In the first season, negative correlations were found between epibenthos abundance and pH and temperature. These relationships may reflect an effect on the growth of macroalgae in the pond, with which the amphipods were strongly associated, rather than a direct effect on the epibenthos. In the second season, a positive correlation existed between temperature and epibenthos abundance, however this was strongly influenced by the very high abundance of Acetes in the last sampling period. No correlations were found between epibenthic fauna biomass and physico-chemical parameters. Abundances of epibenthic fauna were not related to zooplankton densities indicating this source of food was not likely to be a limiting factor. Neither the pond water exchange regime nor moon phase could explain changes observed in abundances of zooplankton or epibenthos assemblages in the first season, however the sampling regime was not designed to specifically investigate these effects. In the second season water exchanges were sampled more rigorously. The density of zooplankton in the outlet water was from 2 to 59% of the density of zooplankton in the pond, and the zooplankton density of the inlet water was from 9 to 50% of the outlet water. The number of zooplankton recruited into the pond from the inlet water, after the prawns were stocked, was negligible and contributed little to changes observed in zooplankton assemblages. Reproduction of barnacles within the pond appeared to play the most important role in changes in the assemblage. Water exchange did, however, appear to play a greater role in the changes observed in epibenthic fauna assemblages. In the last season of sampling the feeding of the dominant epibenthic species, Acetes sibogae, was examined using a combination of gut content and stable isotope analysis. Acetes gained little nutrition directly from the pelleted feed, probably relying primarily on zooplankton as their direct food source. Other dietary items such as macroalgae also played a role in the nutrition of the Acetes. If Acetes numbers were high at the beginning of a season they may compete with the newly stocked prawns for the zooplankton resource. However, they will not compete with the prawns later in the season when the prawns are gaining most of their nutrition from the pelleted feed. Overall it appears that zooplankton are important to the nutrition of the prawns at the beginning of the season when the assemblage is usually dominated by copepods. Later in the season the assemblage is dominated by barnacle nauplii which are recruited from within the pond. The establishment of an abundant assemblage of suitable zooplankton species before stocking prawn postlarvae would appear to be beneficial, if not essential. The assemblage of epibenthic fauna changes throughout the season as new recruits are brought in from outside the pond. Epibenthic faunal assemblages in ponds from southeast Queensland are dominated by Acetes which are not likely to adversely affect the production of prawns unless they are particularly abundant early in the grow out season when the prawns would be utilising the same food resources as Acetes.
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The Gazelle in Ancient Egyptian Art : Image and Meaning

Strandberg, Åsa January 2009 (has links)
This thesis establishes the basic images of the gazelle in ancient Egyptian art and their meaning. A chronological overview of the categories of material featuring gazelle images is presented as a background to an interpretation. An introduction and review of the characteristics of the gazelle in the wild are presented in Chapters 1-2. The images of gazelle in the Predynastic material are reviewed in Chapter 3, identifying the desert hunt as the main setting for gazelle imagery. Chapter 4 reviews the images of the gazelle in the desert hunt scenes from tombs and temples. The majority of the motifs characteristic for the gazelle are found in this context. Chapter 5 gives a typological analysis of the images of the gazelle from offering processions scenes. In this material the image of the nursing gazelle is given particular importance. Similar images are also found on objects, where symbolic connotations can be discerned (Chapter 6). References to healing and regeneration are found, particularly in relationship to the context of the objects. The gazelle is found in a divine context in a limited material (Chapter 7). A discussion of these sources sees a focus on the gazelle as representative for the desert mountains as the setting for death and rebirth. This relates to the gazelle as a feminine image with a connection to the models of female divinity (Chapter 8).

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