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CARACTERIZAÇÃO FLORÍSTICA, DIVERSIDADE E CORRELAÇÃO AMBIENTAL NA FLORESTA NACIONAL DE SÃO FRANCISCO DE PAULA, RS / FLORISTIC CHARACTERIZATION, DIVERSITY AND ENVIRONMENTAL CORRELATION IN THE NATIONAL FOREST OF SÃO FRANCISCO DE PAULA, RSKanieski, Maria Raquel 18 January 2010 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Populations and species are disappearing due to disturbances in the environment caused by human activities. Given the obvious risk of loss of diversity, it is increasingly necessary to take actions concerning preservation, in which safety features are necessary for measuring the variation of diversity in space and time. The
aim of this study was to evaluate the structure and diversity in the arboreal component and natural regeneration in an area of Araucaria forest in the National
Forest of São Francisco de Paula, RS. The vegetation sampling was performed by analyzing 180 subunits of 10m x 10m, where all the arboreal individuals and natural
regeneration were inventoried. The parameters of frequency and density, dispersion indexes of MacGuinnes, Fracker and Brischle and Payandeh, and different alpha and beta indexes of diversity were calculated. The values of alpha indices were correlated with environmental variables by Canonical Correspondence Analysis (CCA). It was found 102 species, distributed in 66 genera and 36 families. The
dispersion indexes showed different patterns for the arboreal component and natural regeneration. The Margalef, Shannon, and the Beta indexes were underestimated,
possibly influenced by the size of sample unit. Index Menhinick represented the diversity in a very real form, even in small sampling units. The indexes of Simpson
and Mcintosh denote low dominance and the equity indexes showed high uniformity in species. The CCA showed that diversity is strongly related to declive, stoniness
and contents of sand and clay, in the arboreal component, and contents of clay, fine sand and silt, in natural regeneration. / Populações e espécies estão desaparecendo devido às perturbações no ambiente por meio de atividades antrópicas. Diante do risco evidente de perda de biodiversidade, deve-se cada vez mais realizar ações de preservação, nas quais são
necessárias ferramentas seguras capazes de medir a variação da diversidade no espaço e no tempo. Objetivou-se com esse trabalho avaliar a estrutura e a diversidade no componente arbóreo e na regeneração natural em área de Floresta
Ombrófila Mista na Floresta Nacional de São Francisco de Paula, RS. A amostragem da vegetação foi realizada por meio de 180 subunidades de 10m x 10m, onde foram inventariados todos os indivíduos arbóreos e da regeneração natural. Foram
calculados os parâmetros de frequência e densidade, os índices de dispersão de MacGuinnes, Fracker e Brischle e Payandeh, e diferentes índices de diversidade alfa e beta. Os valores dos índices alfa foram correlacionados com variáveis ambientais pela Análise de Correspondência Canônica (CCA). Foram encontradas 102 espécies, distribuídas em 66 gêneros e 36 famílias. Os índices de dispersão revelaram diferentes padrões para o componente arbóreo e a regeneração natural.
Os índices de Margalef, Shannon e os índices Beta obtiveram valores subestimados possivelmente influenciados pelo tamanho da unidade amostral. O índice de Menhinick representou a diversidade de forma bastante real mesmo em unidades amostrais pequenas. Os índices de Simpson e Mcintosh denotaram baixa dominância e os índices de equidade demonstraram alta uniformidade nas espécies.
A CCA mostrou que a diversidade está fortemente relacionada à declividade, pedregosidade e teores de areia grossa e argila no componente arbóreo, e a teores de argila, areia fina e silte na regeneração natural.
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Propuesta de diseño de concreto permeable, con distintas relaciones agua cemento y aditivo plastificante, de uso en vías peatonales, como alternativa para reducir el encharcamiento pluvial en calles de Huaraz – Áncash / Design proposal of permeable concrete, with different relationships water cement and plasticizing additive, for use in pedestrian routes, as an alternative to reduce the rainwater stagnation in streets of Huaraz – AncashPeña Palacios, Manfred Romeo, Laguna Jorge, Robert Joel 11 October 2021 (has links)
El presente trabajo de investigación pretende encontrar el diseño de un concreto permeable con la mejor relación agua/cemento, para ser usado en vías peatonales y de bajo tránsito. Además, busca demostrar que su empleo en zonas lluviosas reduce el volumen pluvial y atenúa el impacto que se produce en las poblaciones urbanas, como la ciudad de Huaraz, en las que existen continuas inundaciones debidas al uso de técnicas y métodos que provocan la impermeabilización del suelo.
Se ejecutaron ensayos en laboratorio sobre la base de tres muestras con relaciones agua/cemento de 0.30, 0.35 y 0.40. Luego de someterlas a pruebas de compresión simple, flexión y permeabilidad, se encontró que el diseño que cumple con las mejores características es el de relación agua/cemento 0.30.
Se concluye que, para la realidad problemática descrita, el uso de un concreto permeable con dicha relación es viable en tanto este posee un coeficiente de permeabilidad k de 0.44 mm/s o 0.44 x 10-3 m/s., que se equipara a un suelo de arena limpia con mezcla de grava y se comporta como un suelo granular. Por lo tanto, contribuirá a absorber las escorrentías, incluso en zonas con una pendiente pronunciada. / The present research work aims to find the design of a permeable concrete, with the best water/cement ratio to be used in pedestrian and low-traffic pavements. In addition, it seeks to demonstrate that use in rainy areas reduces the rainfall volume and attenuate the impact that occurs in urban populations, such as the city of Huaraz, where there are continuous floods due to the use of techniques and methods that cause the waterproofing of the soil.
Laboratory tests were performed on the basis of three samples with water/cement ratios of 0.30, 0.35 and 0.40. After undergoing tests of simple compression, bending and permeability, it was found that the design that meets the best characteristics is the one of water/cement ratio 0.30.
It is concluded that, for the problematic reality described, the use of a permeable concrete with this relationship is feasible as it has a permeability coefficient k of 0.44 mm/s or 0.44 x 10-3 m/s, which sand equates to a clean sand soil with gravel mixture. Therefore, it will help absorb runoffs, even in areas with a steep slope. / Tesis
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No changes in Northern Vietnam’s precipitation extremes during rainy season for the time period from 1975 to 2006Goihl, Sebastian 27 February 2019 (has links)
A consequence of climate change may be higher frequencies and higher intensities of extreme climate events all over the world. This paper takes a closer look at the Northern Vietnam climate conditions. The area of interest are the geographical regions North East, North West, Red River Delta and North Central Coast. For research of extreme climate, the data from 72 meteorological stations for the time period from 1975 to 2006 were used and tested for the rainy season with the method of indices for climate change research created by Expert Team on Climate Change Detection (ETCCDI). Apparently, there is a linkage between the indices and topics of social and economic impacts, but this is not a clear fact. The climate change and extreme precipitation indices of the annual total precipitation above the 95th percentile (R95p), the annual total precipitation above the 99th percentile (R99p), the simple precipitation intensity amount (SDII), the annual total precipitation on wet days (PRCPTOT) and a modified annual total precipitation above 50 mm (R50mm) are used in this study. The question, whether there are statistically significant trends is answered using the Mann-Kendall Trend test. The results show that the indices are strongly influenced by the variations of the Vietnamese climate. Hence many stations have no significant trends. For the investigated time period, most of significance trends were decreasing. But there is a positive correlation between the total precipitation in the rainy season (PRCPTOT) and the frequencies of extreme climate events above the indices thresholds from R95p and R99p. Concluding, climate models show that higher total precipitations are likely for the area of interest. Therefore, it can be expected that, in a changing climate, more extreme climate events with higher intensities will occur. / Biến đổi khí hậu có thể dẫn đến sự gia tăng về tần số và cường độ của các hiện tượng thời tiết cực đoan trên toàn thế giới. Nghiên cứu này sẽ xem xét kỹ hơn về các điều kiện khí hậu ở miền Bắc Việt Nam. Địa điểm nghiên cứu bao gồm các khu vực địa lý Đông Bắc, Tây Bắc, Đồng bằng sông Hồng và Bắc Trung Bộ. Để nghiên cứu về khí hậu cực đoan, các dữ liệu trong khoảng thời gian từ 1975 đến 2006 đã được thu thập từ 72 trạm khí tượng. Những dữ liệu này được dùng để kiểm chứng đối với mùa mưa theo phương pháp chỉ số nghiên cứu biến đổi khí hậu của Nhóm chuyên gia về phát hiện biến đổi khí hậu (ETCCCDI). Hiển nhiên có một mối liên hệ giữa các chỉ số với các chủ đề về tác động kinh tế và xã hội, tuy nhiên thực tế này vẫn chưa rõ ràng. Các chỉ số biến đổi khí hậu và mưa cực đoan của tổng mưa hằng năm trên 95 phần trăm (R95p), tổng mưa hằng năm trên 99 phần trăm (R99p), chỉ số cường độ mưa trên ngày (SDII), tổng mưa hằng năm vào những ngày ẩm ướt – mùa mưa (PRCPTOT) và tổng mưa hằng năm biến đổi trên 50mm (R50mm) được sử dụng trong nghiên cứu này. Câu hỏi về sự tồn tại của các xu hướng quan trọng về mặt thống kê được trả lời bằng phương pháp Mann-Kendall Trend. Các kết quả chỉ ra rằng các chỉ số chịu ảnh hưởng lớn từ sự biến đổi của khí hậu Việt Nam. Do vậy, ở một số trạm khí tượng không có các xu hướng có ý nghĩa. Trong khoảng thời gian nghiên cứu, các xu hướng quan trọng đều giảm. Tuy nhiên, có một mối tương quan thuận giữa tổng lượng mưa trong mùa mưa (PRCPTOT) và cường độ của các hiện tượng thời tiết cực đoan trên các cực của chỉ số từ R95P và R99p. Kết luận, các mô hình thời tiết cho thấy tổng lượng mưa lớn hơn có khả năng sẽ xảy ra trên địa bàn nghiên cứu. Vì vậy, có thể phỏng đoán rằng khi thay đổi khí hậu, sẽ diễn ra nhiều hiện tượng thời tiết cực đoan với cường độ cao.
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Investigating the production of secondary metabolites effective in lowering blood glucose levels in Euclea Undulata Thunb. Var Myrtina (Ebenaceae)Botha, Lynette Elizabeth 03 1900 (has links)
Euclea undulata Thunb. var myrtina is a widely distributed shrub in South Africa. The roots are used by traditional healers for the treatment of diabetes. Research indicates that roots contain epicatechin, lupeol as well α-amyrin-3O-β-(5-hydroxy) ferulic acid. It was found that α-amyrin-3O-β-(5-hydroxy) ferulic acid inhibits α-glucosidase while epicatechin lowers glucose levels in the blood. Existing literature also indicates the presence of the naphthoquinone 7-methyl-juglone in the roots, although it was not detected in all cases. Due to its cytotoxic nature, 7-methyl-juglone poses a potential threat when E. undulata is used as medicinal treatment.
In order to assist the effective and safe use of this plant as a treatment for diabetes, this project aims to determine whether the presence of these metabolites is seasonal. It further aims to contribute to more sustainable harvesting methods by investigating stems and leaves in addition to the roots for the presence of these metabolites. / Environmental Sciences / M. Sc. (Environmental Science)
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Estudo meta-analítico do desempenho de bovinos de corte em pastagens tropicais / Meta-analytical study of the performance of beef cattle on tropical pasturesTambara, Antônio Augusto Cortiana 02 March 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Animal performance was evaluated in bovine cattle livestock systems using tropical
pasture based diets through a meta-analysis process, which included a database of
scientific articles, dissertations and theses. Data was tabulated and categorized
identifying the scientific work, the experiment, animals, animal performance, pasture,
supplements and grazing. The conversion efficiency of supplement use was
evaluated in the studies containing control (no supplementation), and calculated as
the change in average daily gain of individual weight (CoEfADGan) or area (ha,
CoEfADGha) per kg of supplement offered. Data distribution from a general database
was assessed. To analyze the factors affecting animal performance variables the
general database was sub-divided into two sub-bases, rainy and dry season. To
evaluate the factors affecting animal performance variables data was weighted by n
treatments and analysis of variance and covariance was used. The average daily
gain of body weight per animal (ADGan, 0.870 vs. 0.611 kg / animal / day) and per
hectare (ADGha vs. 5.76. 4.59 kg / ha / day), as well as daily animal load per hectare
(DALha, 1483 vs. 1211 kg / ha / day) were higher (P <0.05) during the rainy season
than during the dry season. During the rainy season, ADGan was lower in the genus
Brachiaria and superior in the Panicum (P <0.05), but the DALha and ADGha were
higher (P <0.05) in Cynodon. In dry season, ADGan was lower (P <0.05) in the
Brachiaria than in Cynodon and Panicum, and ADGha was higher (P <0.05) in
Panicum. In both dry and rainy seasons, ADGan, ADGha and DALha increased
linearly (P <0.01) with increasing levels of supplementation, which ranged from zero
to 1.6% of live weight (LW). The ADGan increased linearly (P <0.05) and DALha
decreased linearly (P <0.05), while ADGha was quadratically (P <0.05) related to the
increased availability of herbage. Animal performance was linear and positively
correlated with leaf: stem proportion from pastures (P <0.05), both in the rainy and
dry seasons. During the rainy season the best responses in ADGan and ADGha
were obtained from the use of protein supplement compared with supplemental
energy or proteinated salt (P <0.05), while the use of energy supplement enabled a
higher DALha (P <0,05). During the dry season, ADGha was not affected by
supplement type, but the best responses were obtained for ADGan with energy
supplement (P <0.05) while protein supplementation, either through proteinated salt
or protein supplement, was associated with a higher DALha (P <0.05). During the
rainy season animal performance was quadratically (P <0.05) related to live weight
(LW) of animals, and ADGan maximized in animals weighing about 380 kg and
ADGha maximized in animals weighting about 400 kg. In the dry season, ADGan and
ADGha were linearly and positively related animal LW (P <0.05). Pasture neutral
detergent fiber (NDF) content ranged from 46 to 82% in dry matter (DM) and was
quadratically related to ADGan (P <0.05) being that maximum gain was obtained with
NDF content around 66%. Crude protein (CP) of pasture ranged from 1.9 to 21.6% in
DM and was linear and positively correlated with ADGan (P <0.05). The ADGan was
linear and negatively associated with the value obtained by the ratio between the
content (% DM) of total digestible nutrients (TDN) and CP of pasture (P <0.05).
Nitrogen fertilizer was linearly (P <0.05) associated with increased DALha, both in the
rainy and dry seasons. The CoEfADGan and the CoEfADGha decreased lineally (P
<0.05) with increasing animal LW during the rainy season, becoming negative from
around 360 kg. In the rainy season as well as in the dry season, both efficiencies
were also negatively (P <0.05) related to the CP content of pasture, being also
negative from 10% CP, and positive and quadratically (P <0.05) related to the leaf:
stem ratio of the pastures. Highest efficiencies were observed with leaf: stem ratio
3.7:1. During the dry season EfCoGMD and EfCoGAD decreased (P < 0.05) with
the increasing the value obtained by the TDN: CP supplement ratio, becoming
negative from 4,3:1. In conclusion, the meta-analysis enabled the identification of
beef cattle performance in tropical pastures showing that it is influenced in an
integrated manner by factors associated with several features such as climate,
pasture, animal, handling and supplementation. However, the degree to which each
factor influences animal performance could be more accuratelly assessed if
publications were standardized and contained essential information regarding more
detailed methodological descriptions and basic statistical information. / Foi avaliado o desempenho animal em sistemas pecuários bovinos utilizando dietas
à base de pastagens tropicais através de processo meta-analítico, que incluiu na
base de dados artigos científicos, dissertações e teses. Foram tabulados e
categorizados dados de identificação do trabalho científico, do experimento, dos
animais, do desempenho animal, da pastagem, dos suplementos e do método de
pastejo. A eficiência de conversão do uso do suplemento foi avaliada nos estudos
contendo tratamento testemunha (sem suplementação), e calculada como a
variação do ganho médio diário de peso individual (EfCoGMD) ou por área
(EfCoGAD) por kg de suplemento ofertado. Foi avaliada a distribuição dos dados da
base geral e, para analisar os fatores que afetam as variáveis de desempenho
animal, a base geral foi subdividida nas sub-bases águas e secas. Para avaliação
dos fatores que afetam as variáveis de desempenho animal os dados foram
ponderados pelo n dos tratamentos e utilizado análise de variância e covariância. O
ganho médio de peso individual (GMD, 0,870 vs. 0,611 kg/animal/dia) e o ganho por
área (GAD, 5,76 vs. 4,59 kg/ha/dia), assim como a carga animal (CAD, 1483 vs.
1211 kg/ha/dia) foram maiores (P<0,05) no período das águas que no período das
secas. No período das águas o GMD foi menor na Brachiaria e superior no gênero
Panicum (P<0,05), mas a CAD e GAD foram superiores (P<0,05) no Cynodon. Nas
secas, o GMD foi menor (P<0,05) na Brachiaria que no Cynodon ou Panicum, e o
GAD foi maior (P<0,05) no Panicum. Independentemente do período do ano, o
GMD, o GAD e a CAD aumentaram linearmente (P<0,01) com o aumento do nível
de suplementação, o qual variou de zero a 1,6% do peso vivo (PV). O GMD
aumentou linearmente (P<0,05) e a CAD diminuiu linearmente (P<0,05), enquanto o
GAD foi quadraticamente (P<0,05) relacionado com o aumento da oferta de
forragem total. O desempenho animal foi linear e positivamente relacionado com
proporção folha:colmo das pastagens (P<0,05), tanto no período das águas quanto
no período das secas. No período das águas as melhores respostas em GMD e
GAD foram obtidas com o uso de suplemento protéico quando comparado com
suplemento energético ou sal proteinado (P<0,05), enquanto o uso de suplemento
energético possibilitou maior CAD (P<0,05). No período das secas o GAD não foi
afetado pelo tipo de suplemento, mas as melhores respostas para GMD foram
obtidas com suplemento energético (P<0,05) enquanto que a suplementação
proteica, seja através de sal proteinado ou suplemento proteico, foi relacionada com
maior CAD (P<0,05). No período das águas o desempenho animal foi
quadraticamente (P<0,05) relacionado com o peso vivo (PV) dos animais, sendo o
GMD maximizado com animais pesando em torno de 380 kg e o GAD maximizado
com animais de 400 kg. Nas secas o GMD e o GAD foram linear e positivamente
relacionados com o PV dos animais (P<0,05). O teor de fibra em detergente neutro
(FDN) da pastagem variou de 46 a 82 % na matéria seca (MS) e foi quadraticamente
relacionado com o GMD (P<0,05) sendo que o máximo GMD foi obtido com teor de
FDN em torno de 66%. O teor de proteína bruta (PB) da pastagem variou de 1,9 a
21,6 % na MS e foi linear e positivamente relacionado com GMD (P<0,05). O GMD
foi linear e negativamente associado com o valor obtido pela razão (relação) entre o
teor (% na MS) de nutrientes digestíveis totais (NDT) e PB da pastagem (P<0,05). A
adubação nitrogenada foi linearmente (P<0,05) relacionada com aumento da CAD
tanto no período das águas como no período das secas. A EfCoGMD e a EfCoGAD
diminuíram linearmente (P<0,05) com o aumento do PV dos animais no período das
águas, passando a serem negativas a partir de em torno de 360 kg. Tanto nas águas
como nas secas, ambas as eficiências também foram negativamente (P<0,05)
relacionadas com o teor de PB da pastagem, passando a serem negativas a partir
de 10% de PB, e positiva e quadraticamente (P<0,05) relacionadas com a relação
folha:colmo das pastagens. Máximas eficiências foram observadas com relação
folha:colmo em torno de 3,7:1. No período das secas a EfCoGMD e a EfCoGAD diminuíram linearmente (P<0,05) com o aumento do valor observado na relação
NDT:PB do suplemento, passando a serem negativas a partir de 4,3:1. Em
conclusão, a meta-análise possibilitou identificar que o desempenho de bovinos de
corte em pastagens tropicais é influenciado de forma integrada por fatores
associados às características do clima, das pastagens, dos animais, do manejo e da
suplementação. Contudo, o grau de influência de cada fator seria melhor definido se
as publicações nessa área de conhecimento fossem padronizadas e contivessem
informações mínimas tanto em relação à descrição da metodologia como em relação
à presença de informações estatísticas básicas.
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Influence of climate change on flood and drought cycles and implications on rainy season characteristics in Luvuvhu River CatchmentDagada, K. 18 September 2017 (has links)
MESHWR / Department of Hydrology and Water Resources / This study dealt with the influence of climate variability on flood and drought cycles and implications on
rainy season characteristics in Luvuvhu River Catchment (LRC) in Limpopo of South Africa. Extreme
weather events resulting in hazards such as floods and droughts are becoming more frequent due to
climate change. Extreme events affect rainy season characteristics and hence have an influence on water
availability and agricultural production. Annual temperature was obtained from Water Research
Commission for stations 0723485W, 0766628W and 0766898W from 1950-2013 were used to show/or
confirm if there is climate variability in LRC. Daily rainfall data was obtained from SAWS for stations
0766596 9, 0766563 1, 0723485 6 and 0766715 5 were used to detect climate variability and determine
the onset, duration and cessation of the rainy season. Streamflow data obtained from the Department of
Water and Sanitation for stations A9H004, A9H012, and A9H001 for at least a period of 30 years for
each station were used for climate variability detection and determination of flood and drought cycles.
Influence of climate variability on floods and droughts and rainy season characteristic were determined in
the area of study. Trends were evaluated for temperature, rainfall and streamflow data in the area of study
using Mann Kendall (MK) and linear regression (LR) methods. MK and LR detected positive trends for
temperature (maximum and minimum) and streamflow stations. MK and LR results of rainfall stations
showed increasing trends for stations 0766596 9, and 0766563 1 whereas stations 0723485 6 and
0766715 5 showed decreasing trends. Standardized precipitation index (SPI) was used to determine floods
and droughts cycles. SPI results have been classified either as moderately, severely and extremely
dry or, moderately, very and extremely wet. This SPI analysis provides more details of
dominance of distinctive dry or wet conditions for a rainy season at a particular station. Mean
onset of rainfall varied from day 255 to 297, with 0766715 5 showing the earliest onset compared to the
rest of the stations. Cessation of rainfall for most of the hydrological years was higher than the mean days
of 88, 83 and 86 days in 0766596 9, 0766563 1 and 0723485 6 stations. Mean duration of rainfall varied
from 102 to 128, with station 0766715 5 showing shortest duration of rainfall. The results of the study
showed that the mean onset, duration and cessation were comparable for all stations except 0766715 5
which had lower values. The study also found that climate variability greatly affects onset, duration and
cessation of rainfall during dry years. This led to late onset, early cessation and relatively short duration
of the rainfall season. Communities within the catchment must be educated to practice activities
such as conservation of indigenous plants, reduce carbon dioxide emissions.
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