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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.
1

Tree colonization of abandoned agricultural clearings in seasonal tropical Montane forest in Northern Thailand

Hardwick, Kate January 1999 (has links)
No description available.
2

Vegetation development on set-aside arable land : the role of animals

Wilby, Andrew January 1996 (has links)
No description available.
3

A hybrid model to estimate natural recruitment and growth in stands following mountain pine beetle disturbance

Sattler, Derek Felix 05 1900 (has links)
A method of linking SORTIE-ND and PrognosisBC was developed for the purpose of predicting natural regeneration and forecasting future stand conditions in mountain pine beetle (Dendroctonus ponderosae Hopkins - MPB) attacked stands in the Interior Douglas-fir (IDF) and Sub-Boreal Spruce (SBS) biogeoclimatic ecosystem zones of central and southeastern British Columbia. PrognosisBC, a spatially-implicit growth model, lacked a submodel suitable for predicting natural regeneration in unsalvaged MPB-disturbed stands. To fill this gap, estimates of regeneration (trees <7.5 cm diameter at breast height - DBH) were supplied to PrognosisBC using the light-mediated forest dynamics model SORTIE-ND and the linked model was used to forecast future stand conditions. In order to improve results, a density-dependent system of crown allometry equations to predict crown depth and crown radius was developed and then added to SORTIE-ND. The equations used stand-level measures of stems ha-¹, basal area (m² ha-¹), and the basal area of trees taller than the target tree to explicitly account of the effects of crowding on the crown axes. Additionally, crown radius and crown depth were used as dependent regressors. The equations were fit using a nonlinear three-stage least squares estimator and generally provided good estimates of crown depth and crown radius for lodgepole pine (Pinus contorta var. latifolia), hybrid spruce (Picea engelmannii x glauca (Moench) Voss), Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco) and trembling aspen (Populus tremuloides Michx.). Tests of the hybrid model with the improved system of crown allometry equations were performed using reconstructed plot data collected from natural stands disturbed by MPB 25-years ago. The hybrid model provided good estimates (small mean bias and low root mean square error) for the basal area of advance regeneration (2 < DBH < 7.5 cm) for lodgepole pine (Pinus contorta var. latifolia). The best estimates were achieved when trees <7.5 cm DBH were transferred from SORTIE-ND to PrognosisBC 15-years after MPB-disturbance. For trees <2 m in height, poor estimates of stems ha-¹ where obtained. Despite the shortcomings with respect to trees <2 m tall, the results suggest that linking SORTIE-ND and PrognosisBC is an effective method of building a hybrid model capable of being used in MPB-disturbed forests. However, full parameterization of the SORTIE-ND model is likely needed to obtain accurate estimates for all sizes of natural regeneration.
4

A hybrid model to estimate natural recruitment and growth in stands following mountain pine beetle disturbance

Sattler, Derek Felix 05 1900 (has links)
A method of linking SORTIE-ND and PrognosisBC was developed for the purpose of predicting natural regeneration and forecasting future stand conditions in mountain pine beetle (Dendroctonus ponderosae Hopkins - MPB) attacked stands in the Interior Douglas-fir (IDF) and Sub-Boreal Spruce (SBS) biogeoclimatic ecosystem zones of central and southeastern British Columbia. PrognosisBC, a spatially-implicit growth model, lacked a submodel suitable for predicting natural regeneration in unsalvaged MPB-disturbed stands. To fill this gap, estimates of regeneration (trees <7.5 cm diameter at breast height - DBH) were supplied to PrognosisBC using the light-mediated forest dynamics model SORTIE-ND and the linked model was used to forecast future stand conditions. In order to improve results, a density-dependent system of crown allometry equations to predict crown depth and crown radius was developed and then added to SORTIE-ND. The equations used stand-level measures of stems ha-¹, basal area (m² ha-¹), and the basal area of trees taller than the target tree to explicitly account of the effects of crowding on the crown axes. Additionally, crown radius and crown depth were used as dependent regressors. The equations were fit using a nonlinear three-stage least squares estimator and generally provided good estimates of crown depth and crown radius for lodgepole pine (Pinus contorta var. latifolia), hybrid spruce (Picea engelmannii x glauca (Moench) Voss), Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco) and trembling aspen (Populus tremuloides Michx.). Tests of the hybrid model with the improved system of crown allometry equations were performed using reconstructed plot data collected from natural stands disturbed by MPB 25-years ago. The hybrid model provided good estimates (small mean bias and low root mean square error) for the basal area of advance regeneration (2 < DBH < 7.5 cm) for lodgepole pine (Pinus contorta var. latifolia). The best estimates were achieved when trees <7.5 cm DBH were transferred from SORTIE-ND to PrognosisBC 15-years after MPB-disturbance. For trees <2 m in height, poor estimates of stems ha-¹ where obtained. Despite the shortcomings with respect to trees <2 m tall, the results suggest that linking SORTIE-ND and PrognosisBC is an effective method of building a hybrid model capable of being used in MPB-disturbed forests. However, full parameterization of the SORTIE-ND model is likely needed to obtain accurate estimates for all sizes of natural regeneration.
5

Žėlimas juodalksnynuose ir jį lemiantys veiksniai / Natural regeneration in the Black Alder forests

Kubilius, Tomas 15 June 2009 (has links)
Darbo tikslas – Ištirti žėlimo intensyvumą juodalksnynuose ir kokybę lemiančius veiksnius. Darbo uždaviniai – Ištirti žėlimo intensyvumą juodalksnynuose nuo motinio medyno amžiaus, nuo augavietės ir buvusio medyno rūšinės sudėties. Nustatyti žėlimo intensyvumą nuo kirtimui naudotos technologijos. Darbo objektas – Kazlų rūdos mokomosios miškų urėdijos Bagotosios girininkijos juodalksnynai. Darbo metodai – Tyrimui buvo atrinkta 18 juodalksnio biržių, nukirstų 1996-2006 metais. Parenkant kirtavietes, buvo atsižvelgta į tai, kad būtų skirtingos kirtimų technologijos, kad būtų įvairesnėse augavietėse, kad būtų įvairesnė rūšinė sudėtis, bet jose vyrautu juodalksnis. Atrinktuose plotuose buvo uždėtos apskaitos aikštelės, kuriuose siekiant nustatyti juodalksnio žėlimo intensyvumą, buvo atlikti tyrimai: aprašyta ploto charakteristika, nustatytas atauginių ir sėklinių juodalksnio savaiminukų, tame skaičiuje gyvybingų skaičius, kitų medžių rūšių savaiminukų skaičius, išmatuotas aukštesnių medelių aukštis ir storis. Apdorojant tyrimų duomenis, kiekvienam plotui nustatyta atauginio ir sėklinio juodalksnio žėlimo kokybė ir intensyvumas. Pagal miško atkūrimo ir įveisimo nuostatus įvertinta juodalksnio jaunuolynų būklė ir žėlinių kokybė. Darbo rezultatai – Kas met šalyje plynai iškertama šimtai hektarų juodalksnynų. 87% visų nukirstų juodalksnio kirtaviečių paliekamos žėlimui. Biržės sėkmingai želdosi tada, kai medynai kertami žiemą, kertama sėkliniais metais, kirtavietėse paliekami geri iš... [toliau žr. visą tekstą] / Goal of study – to find the reason of natural regeneration of black alders forests. Task of study – To find the intensity of the regeneration of black alders and to indentify how much does it depends on the main sort, age and the area. To find the intensity of the regeneration which depends on cutting technology Object of study – Black alders forests in Kazlu Rudas ferestry enterprice. Methods of study – There was 18 different areas of blac alders forests cutted in 1996-2006. For the researc of the areas there were been looking for the different technologies of the cutting, with a different forests, but most of all of black alders. In that areas were made special places of the counting, there were done these types of analysis: describtion of the area, counting of the natural regeneration of black alders, regeneration of another type of trees, intensity and the quality of the regeneration of black alders. Made a report of the condition and the quality of a young black alders forests. Results of study– There were cutted hundreds of hectares of black alders forests each year. About 87% of all cutted black alders areas were left to generate. The cutted areas are sucsesfully regenerating if they were cutted in winter time, and the year of the seeding. It is very important to leave the goog quality trees which had grown from the seeds. In the areas there were cutted using the footstalk technology the regeneration of black alders forests was good. In the most of all areas there... [to full text]
6

A hybrid model to estimate natural recruitment and growth in stands following mountain pine beetle disturbance

Sattler, Derek Felix 05 1900 (has links)
A method of linking SORTIE-ND and PrognosisBC was developed for the purpose of predicting natural regeneration and forecasting future stand conditions in mountain pine beetle (Dendroctonus ponderosae Hopkins - MPB) attacked stands in the Interior Douglas-fir (IDF) and Sub-Boreal Spruce (SBS) biogeoclimatic ecosystem zones of central and southeastern British Columbia. PrognosisBC, a spatially-implicit growth model, lacked a submodel suitable for predicting natural regeneration in unsalvaged MPB-disturbed stands. To fill this gap, estimates of regeneration (trees <7.5 cm diameter at breast height - DBH) were supplied to PrognosisBC using the light-mediated forest dynamics model SORTIE-ND and the linked model was used to forecast future stand conditions. In order to improve results, a density-dependent system of crown allometry equations to predict crown depth and crown radius was developed and then added to SORTIE-ND. The equations used stand-level measures of stems ha-¹, basal area (m² ha-¹), and the basal area of trees taller than the target tree to explicitly account of the effects of crowding on the crown axes. Additionally, crown radius and crown depth were used as dependent regressors. The equations were fit using a nonlinear three-stage least squares estimator and generally provided good estimates of crown depth and crown radius for lodgepole pine (Pinus contorta var. latifolia), hybrid spruce (Picea engelmannii x glauca (Moench) Voss), Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco) and trembling aspen (Populus tremuloides Michx.). Tests of the hybrid model with the improved system of crown allometry equations were performed using reconstructed plot data collected from natural stands disturbed by MPB 25-years ago. The hybrid model provided good estimates (small mean bias and low root mean square error) for the basal area of advance regeneration (2 < DBH < 7.5 cm) for lodgepole pine (Pinus contorta var. latifolia). The best estimates were achieved when trees <7.5 cm DBH were transferred from SORTIE-ND to PrognosisBC 15-years after MPB-disturbance. For trees <2 m in height, poor estimates of stems ha-¹ where obtained. Despite the shortcomings with respect to trees <2 m tall, the results suggest that linking SORTIE-ND and PrognosisBC is an effective method of building a hybrid model capable of being used in MPB-disturbed forests. However, full parameterization of the SORTIE-ND model is likely needed to obtain accurate estimates for all sizes of natural regeneration. / Forestry, Faculty of / Graduate
7

Beržo žėlimo ypatumai plynose kirtavietėse Šiaulių miškų urėdijoje / Natural regeneration of birch in the clear - cut areas in Šiauliai state forest enterprise

Nagrockis, Kęstutis 01 June 2011 (has links)
Tyrimų tikslas - Nustatyti beržynų atsikūrimo galimybes plynose kirtavietėse. Darbo objektas – Šiaulių miškų urėdijos 4 ir 6 metų amžiaus plynos kirtavietės Lc, Ld, Ud, Pcn ir Pdn augavietėse. Metodai – Beržo žėlinių kiekybiniai tyrimai atlikti stačiakampėse apskaitos aikštelėse, kurios atidėtos vadovaujantis miško atkūrimo ir įvesimo nuostatais. Tyrimai atlikti kiekvienoje augavietėje atliekant bent po 3 pakartojimus. Apskaitos aikštelėse nustatytas žėlinių tankis, o išmatavus aukštį, žėliniai suskirstyti į 4 aukštumo grupes: iki 0,5 m aukščio, nuo 0,5 iki 1,0 m aukščio, nuo 1,0 iki 1,5 m aukščio ir virš 1,5 m aukščio. Nustatytas žolinės dangos agresyvumo laipsnis žėlimui ir suskirstytas į 6 grupes. Gretimo medyno įtaka nustatyta atidedant apskaitos aikšteles 15, 35, 55 metrų atstumu nuo vakariniame kirtavietės pakraštyje esančio medyno. Žėliniai vertinti pagal augimo vieta: ruoštoje ar neruoštoje dirvoje. Nustatyta atsikūrimo galimybė skirtingose augavietėse, dirvos paruošimo, konkuruojančios augalijos įtaka žėlinių tankiui ir gyvybingumui. Gyvybingumas nustatytas pagal miško atkūrimo ir įveisimo nuostatus. Rezultatai – Palankiausios sąlygos natūraliam žėlimui nustatytos Lc ir Pcn augavietėse. Nustatyta vakariniame kirtavietės pakrašyje esančo medyno sudėties įtaka žėlinių tankiui. Didėjant beržo kiekiui minėtų medynų sudėtyje, žėlinių tankis didėja. Optimaliausias atstumas, nuo vakariniame kirtavietės pakraštyje esančio medyno, yra 35 metrai. Išaiškinta teigiama dirvos... [toliau žr. visą tekstą] / The aim of our investigation – To determine abilities of birch regeneration in clear cut areas. The object of investigation - 4 and 6 age clear cut areas in Lc, Ld, Ud, Pcn Pdn forest sites of Šiauliai State Forest Enterprise. Methods – Quantitative research of birch seedlings was carried out in rectangular sample plots according to the methodology of statute of reforestation and afforestation with 3 repetition in each forest site. There were determined: density of seedlings, height (seedlings were classified in 4 groups: up to 0,5 m; from 0,5 m to 1,0 m; from 1,0 m to 1,5 m and more than 1,5 meter in height), shading degree of herbal plants for birch regeneration was classified in 6 groups. Smaple plots were set out in 15, 35 and 55 meters from the edge of western side stand for detemination the influence of it. Besides, it was determine the influence of soil preparation, possibilities of birch regeneration in different forest sites, shading plants influence on vitality and density of birch seedlings. Results – it was determined that the most favorable conditions for birch regeneration was in Lc and Pcn forest sites. The higher content of birch in adjacent stand caused the higher density of birch seedlings in clear cut areas. The most optimum distance for birch regeneration was 35 meters from the adjacent western side stand. Besides, it was determined the positive influence of soil preparation on birch seedlings density (unprepared soil had 25 % less seedlings)... [to full text]
8

Avaliação do potencial de regeneração natural e o uso da semeadura direta e estaquia como técnicas de restauração / Assessing the potential of natural regeneration and the use of direct seeding and cutting and restoration techniques

Aguirre, Andrea Garafulic 06 March 2012 (has links)
A escolha e caracterização do ecossistema de referencia são fundamentais para orientar as ações de restauração. Além disso, novas técnicas devem ser testadas para aumentar a riqueza e o potencial da restauração ecológica, sendo duas delas a semeadura direta e a estaquia. A área de estudo corresponde a um trecho de pastagem e três fragmentos de Floresta Estacional Semidecidual, no município de Piracaia, São Paulo (23º00\'58\'\' a 23º00\'31\'\' S e 46º17\'04\'\' a 46º16\'26\'\' W). Esta dissertação teve como objetivo, no primeiro capitulo, elaborar um levantamento florístico dos fragmentos florestais e da regeneração natural na área de pasto do Projeto Cachoeira. No segundo capitulo avaliou-se o potencial de utilização da semeadura direta, objetivando-se: i) Estudar espécies nativas potenciais para uso da técnica; ii) Avaliar se a densidade de plântulas após seis meses foi suficiente para se obter uma ocupação de 1667 mudas por hectare; iii) Avaliar diferentes condições (tratamentos) da semeadura de espécies nativas para potencializar a emergência e estabelecimento das plântulas. O terceiro capitulo teve como objetivos: i) avaliar a capacidade de estabelecimento de estacas de grande porte diretamente no campo em 5 tratamentos (duas concentrações de hormônio AIB 4000 e 6000 ppm; com e sem a aplicação de hidrogel; e testemunha); ii) avaliar o enraizamento de estacas de pequeno porte em câmara de nebulização em 3 tratamentos (em duas concentrações de hormônio AIB 4000 e 6000 ppm e testemunha). O resultado do estudo floristico realizado no fragmento florestal 1 resultou na amostragem de 38 famílias, 72 gêneros, 87 espécies. No fragmento 2 foram amostradas 40 famílias, 73 gêneros, 86 espécies. No fragmento 3 foram amostradas 37 famílias, 79 gêneros, 104 espécies. Na área de pastagem obteve-se 20 famílias, 27 gêneros, 39 espécies. Na analise floristica geral foram amostradas 156 espécies, 112 gêneros, pertencentes a 51 famílias. O resultado da semeadura mostrou que está técnica é viável. Avaliando-se após 180 dias o melhor tratamento (sem hidratação recoberto com terra) apresentou 3817 indivíduos ha -1, obtendo o maior índice de estabelecimento. Devemos salientar que através da utilização de diversos tratamentos, pode-se criar distinto microssitios, permitindo o aumento da riqueza e diversidade de espécies estabelecidas tanto pela semeadura direta, quanto pela regeneração natural. A incorporação ou recobrimento das sementes se mostrou de extrema importância para a germinação e estabelecimento destas. Os resultados demonstrados para a técnica de estaquia sugerem que são necessários novos estudos e aprimoramentos para que esta técnica se torne viável nas condições avaliadas. Para estacas de grande porte, observou-se após 45 dias uma mortalidade de 100%. Isto provavelmente ocorreu devido à baixa resistência das estacas à dessecação, o que pode ser verificado com as estacas de pequeno porte na Câmera de Nebulização, onde por problemas mecânicos as estacas ficaram sem aspersão de água por dois dias e novamente a mortalidade foi total. Entretanto observações empíricas sugerem que espécies de subbosque apresentam potencial para a técnica de estaquia nas condições de Câmera de Nebulização, assim como alguns estudos apontam que está técnica pode ser eficaz para algumas espécies de Cerrado. / The selection and characterization of the ecosystem of reference are essential to guide restoration actions. In addition, new techniques must be tested to increase the wealth and potential of ecological restoration, two of these new techniques are direct seeding and cuttings. The study area corresponds to a stretch of pasture and three fragments of semideciduous forest in the municipality of Piracaia, Sao Paulo (23 ° 00\'58\'\'23 ° 00\'31\'\'Sand 46 º 17\'04\'\'to 46 16\'26\'\'W). This work aims, in the first chapter, prepare a floristic survey of forest fragments and natural regeneration in the area of pasture Project Waterfall. In the second chapter evaluates the potential use of direct seeding, aiming to: i) to study native species for potential use of the technique, ii) Evaluated the density of seedlings after six months was sufficient to obtain an occupancy rate of 1666 seedling per hectare iii) evaluated different conditions (treatments) of native species sowing to potentiate the emergence and seedling establishment. The third chapter aimed to: i) evaluated the ability for large cuttings directly in the field in five treatments (two hormone concentration 4000 and 6000 ppm IBA, with and without the application of hydrogel, and control), ii) evaluate the rooting of small cuttings in a fogging chamber in three treatments (two hormone concentration 4000 and 6000 ppm and control). The result of floristic study conducted in the forest fragment 1 resulted in a sample of 38 families, 72 genera, 87 species. In fragment 3 were sampled 37 families, 79 genera, 104 species. In the pasture area was obtained 20 families, 27 genera, 39 species. In general floristic analyses werw sampled 156 species, 122 genera, belonging to 51 families. The result showed that the seeding technique is feasible. Evaluating after 180 days the best treatment (not covered with soil moisture) showed 3817 individuals ha -1, obtaining the highest rate of establishment. We note that through the use of several treatments, you can create separate micros sites, allowing the increase of wealth and diversity of species established both by direct sowing as by natural regeneration. The incorporation or coating of the seeds proved to be extremely important for germination. The incorporation or coating of the seeds proved to be extremely important for germination and establishment of these. The results shown for the technique of cutting suggest that further studies and improvements for this technique to be viable under the conditions evaluated. For cuttings of large size, was observed after 45 days a 100% of mortality. This was probably due to low resistance of the cutting to desiccation o, which can be verified with the small cuttings in Fogging Camera. Because mechanical problems these small cuttings were without water for two days and again total mortality was showed again. However empirical observations suggest that understory species have potential for the technique of cutting in Fogging Camera conditions, as well as some studies suggest that this technique can be effective for some species of the Cerrado.
9

Padrões da comunidade de trepadeiras e suas relações com a biomassa arbórea e a regeneração natural em uma Floresta Estacional Semidecidual em Piracicaba, SP: implicações no manejo de fragmentos florestais degradados / Climbing plants community patterns and its relations with tree biomass and natural regeneration in a Seasonal Semidecidual Forest: Implications for the management of degraded forest fragments

Mello, Felipe Nery Arantes 08 October 2015 (has links)
Devido ao histórico processo de exploração e conversão do uso do solo, as florestas tropicais hoje se encontram altamente fragmentadas e com os remanescentes de vegetação sobre constante pressão, como é possível observar para Florestas Estacionais Semideciduais do Estado de São Paulo. O aumento na frequência e intensidade de fatores de perturbação em pequenos fragmentos florestais pode ocasionar uma proliferação desequilibrada de plantas trepadeiras que acabam por contribuir com a degradação florestal iniciada pelas perturbações. Isto se reflete na crescente demanda por resolução de problemas ligados ao manejo de tais plantas em fragmentos florestais como forma de restauração florestal. Sendo assim o presente trabalho teve como objetivos caracterizar a comunidade de plantas trepadeiras em diferentes setores de conservação de um fragmento de Floresta Estacional Semidecidual degradado e avaliar os padrões de associação de variáveis como densidade, diâmetro e biomassa de trepadeiras com variáveis estruturais da flroesta como a regeneração natural e a biomassa arbórea da área total e estratos de conservação. As variáveis que mostraram associação em pelo menos algum estrato foram selecionados para compor modelos candidatos utilizando a densidade de regeneração natural como variável resposta, sendo feito uma seleção do melhor modelo através de Akaike Information Criterion (AIC). Utilizando os modelos selecionados como indicativos, foram traçados e discutidos possíveis estratégias de manejo. Foram amostradas 2323 plantas trepadeiras pertencentes a 62 espécies, 50 gêneros e 20 famílias botânicas. As espécies Mansoa difficilis, Lundia obliqua, Dicella bracteosa, Fridericia triplinervia, Serjania fuscifolia, Adenocalymma marginatum, Bignonia sciuripabula e Bignonia campanulata representaram 50% da abundância total de indivíduos. Os resultados mostraram que a área possui uma grande riqueza e diversidade de plantas trepadeiras, sendo registrada uma abundância heterogênea nos diferentes estratos de conservação, com espécies exclusivas para cada um deles. Algumas espécies como Bignonia campanulata apresentou alta densidade em estratos \"pouco degradados\", média em \"degradados\" e não foi encontrada em \"muito degradados\". Em geral as variáveis de plantas trepadeiras não mostraram tendências de associação com a regeneração natural e biomassa arbórea quando considerado a área total, porém algumas associações moderadas foram obtidas em diferentes estratos de conservação. O modelo selecionado para área total e para setores \"degradado\" e \"muito degradado\" mostrou um efeito negativo da densidade de plantas trepadeiras e positivo da biomassa arbórea sobre a regeneração natural, sendo que para o setor \"pouco degradado\" o melhor modelo não mostrava qualquer efeito de preditoras. Os resultados mostram que parâmetros como a densidade de plantas trepadeiras e a biomassa arbórea do fragmento florestal influênciam a regeneração natural, sendo taís características importantes de serem levadas em conta em atividades de manejo através do corte de trepadeiras, sendo sugerido controle da densidade destas plantas e manutenção e promoção da biomassa arbórea em fragmentos florestais degradados. / Due to the historical process of exploration and conversion of land use in tropical forest, nowadays these regions are highly fragmented and the remaining vegetation under constant pressure, what can be seen in the semideciduous seasonal forests of São Paulo, Brazil. The increase in the frequency and intensity of disturbance factors in small forest fragments can cause an unbalanced proliferation of climbing plants that end up contributing to forest degradation initiated by the disturbances. Demand for solving problems related to the management of these plants as a forest restoration tool has increasingly risen. Thus, the present study aimed to characterize the pattern of climbing plants community in different conservation areas of a small and degraded Seasonal Semidecidual forest fragment and evaluate the patterns of association within variables such as density, diameter and biomass with forest structural variables as the natural regeneration and the tree biomass of the total area and conservation sectors. The variables that were associated with at least some strata were selected to compose candidate models using natural regeneration density as the response variable, being made a selection of the best model using Akaike Information Criterion (AIC). Using the models selected as guides, were drawn and discussed possible management strategies. Were sampled 2323 individuals from climbing plants belonging to 62 species, 50 genera and 20 botanical families. The species difficilis Mansoa, oblique Lundia, bracteosa Dicella, triplinervia Fridericia, Serjania fuscifolia, Adenocalymma marginatum, Bignonia Bignonia campanulata sciuripabula and accounted for 50% of the total abundance of individuals. The results showed that the area has a wealth and diversity of climbing plants, and registered a motley abundance in different conservation sectors, with exclusive species for each of them. Some species as Bignonia campanulata showed high density in sectors \"little degraded,\" few individuals in \"degraded\" sectors and was not found in sectors \"highly degraded\". In general, the variables of climbing plants don\'t showed strong trends of association with natural regeneration and tree biomass when considering the total area, but some moderate associations were obtained in different conservation sectors. The model selected for total area and sectors \"degraded\" and \"highly degraded\" showed a negative effect by the climbing plants density and a positive effect by the tree biomass on natural regeneration. In the other hand the \"little degraded\" sector best model showed no effect of any precditive variable. By the results, the author suggests that the management focused on the control of density and maintenance and promotion of tree biomass would be more suitable in degraded forest fragments.
10

Caracterização da dinâmica da regeneração natural de duas fisionomias de Floresta Ombrófila Densa degradadas na região da Juréia, Litoral Sul/Vale do Ribeira, SP / Characterization of the dynamics of natural regeneration in two physiognomies of Atlantic Rainforest degraded in the Juréia, South Coast/ Ribeira Valley, SP.

Moura, Claudio de 28 November 2016 (has links)
Este trabalho objetivou analisar a dinâmica da regeneração natural de duas áreas de Floresta Ombrófila Densa (FOD) com idades diferentes de regeneração, sendo uma de FOD Submontana de oito anos (A1- Miracatu) e outra FOD das Terras Baixas de 33 anos (A2-Peruíbe), degradadas para implantação da bananicultura. A caracterização da regeneração foi feita por meio de levantamento florístico e fitossociológico realizado pelo método de parcelas, onde em cada área foram implantadas cinco parcelas de 10 x 25 m, totalizando 2.500 m². O material botânico de todos os indivíduos de porte arbustivo-arbóreo 1 m de altura foi coletado e foram registrados a altura e o perímetro do caule a 1,3 m do solo. Após a identificação das espécies foram classificadas as suas síndromes de dispersão, assim como foram estabelecidos os grupos sucessionais aos quais pertenciam. A estrutura florestal foi estudada através do cálculo dos parâmetros de densidade e dominância, tanto absoluta quanto relativa, além do valor de cobertura (VC), realizados com o Fitopac, e também os índices de similaridade de Jaccard (ISj), de diversidade de Shannon (H) e equabilidade (J). Na A1 foram levantados 1.440 indivíduos de 149 espécies e 59 famílias e na A2 foram levantados 1.023 indivíduos de 172 espécies e 56 famílias. As famílias de maiores riquezas de espécies da A1 foram Melastomataceae (29), Myrtaceae (15), Fabaceae (10), Rubiaceae (9) e Asteraceae (6), e na A2 foram Myrtaceae (29), Piperaceae (19), Fabaceae (18), Melastomataceae (13) e Rubiaceae (11), onde na A1 predominaram as espécies pioneiras e secundárias iniciais (36,91%) e na A2 as tardias e de sub-bosque (38,96%) e a síndrome de dispersão predominante em ambas as áreas foi a zoocoria para 54,36% das espécies de A1 e 65,11% em A2. As espécies com maiores valores de VC da A1 foram Tibouchina pulchra, Leandra variabilis, Miconia cinnamomifolia, Piptocarpha macropoda, Vernonanthura discolor e Myrsine coriacea que somaram 64,8% de VC. Na A2 as espécies com os maiores valores de VC foram Euterpe edulis, T. pulchra, Hyeronima alchorneoides, Bathysa australis, Ficus insipida, Cyatheaceae sp.1, Piper gaudichaudianum e Psychotria nuda perfazendo 58,12% do VC. Na A1 as espécies com maiores densidades foram L. variabilis (DeA=2.568 ind./ha e DeR=24,21%), T. pulchra (DeA=1.360 ind./ha e DeR=12,82%), M. cinnamomifolia (DeA=1.088 ind./ha e DeA=10,26%) e H. alchoneoides (DeA=408 ind./ha e DeA=3,85%). A2 possui uma floresta com estrutura mais complexa, apresentou flora similar a quatro estudos realizados nas regiões do Vale do Ribeira e Baixada Santista, e A1 apresentou baixa similaridade. Na A1 as espécies pioneiras destacaram-se na estrutura e na A2 o papel das espécies dos diferentes grupos sucessionais foi mais equilibrada. O componente da vegetação amostrado em A1 apresentou H= 3,330 nat. ind-1 e J = 0,666 e em A2 H= 3,919 nat. ind-1 e J = 0,761. A regeneração natural mostrou-se capaz de promover a erradicação de 95,45% a 100% das bananeiras em A1 enquanto em A2, após 33 anos, nenhuma bananeira remanescente foi observada. / This work aimed to analyze the dynamics of natural regeneration of two areas with physiognomies and different ages of regeneration, with a Dense Ombrophilous Forest (DOF) Submontane (A1-Miracatu-8 years) and another on DOF lowland (A2-Peruíbe-33 years), degraded to deployment of the banana plantation. The characterization of the regeneration was made by using floristic and phytosociological survey, which was performed by methods of plots. Were deployed five 10 x 25 m plots in each area, totaling 2,500 m². The botanical material of all individuals to carry shrub-tree 1 m tall was collected and have been registered, the height and circumference at breast height to 1.3 m above the ground. After the identification of the species have been classified their dispersal syndromes, as well as successional groups to which they belonged were established. The forest structure was studied by calculating the parameters of density and dominance, both absolutely and relative, in addition to the coverage value (VC), performed with the Fitopac, and also the indexes of similarity of Jaccard (ISj), Shannon diversity (H \') and equability (J \'). In A1 were raised 1,440 individuals of 149 species and 59 families and A2 were surveyed 1,023 individuals of 172 species and 56 families. The families of most species richness of A1 were Melastomataceae (29), Myrtaceae (15), Fabaceae (10), Rubiaceae (9) and Asteraceae (6), and A2 were Myrtaceae (29), Piperaceae (19), Fabaceae (18), Melastomataceae (13) and Rubiaceae (11), where the A1 predominated the pioneer and early secondary species (36.91%) and A2 late and understory (38.96%) and predominant dispersion syndrome in both areas was zoochory to 54.36% of the species A1 and 65,11% in A2. The species with the highest values of VC the A1 were Tibouchina pulchra, Leandra variabilis, Miconia cinnamomifolia, Piptocarpha macropoda, Vernonanthura discolor and Myrsine coriacea totaling 64.8% of VC.. In A2 the species with higher VC were Euterpe edulis, T. pulchra, Hyeronima alchorneoides, Bathysa australis, Ficus insipida, Cyatheaceae 1, Piper gaudichaudianum and Psychotria nuda totaling 58,12% of VC. A1 in the species with the highest densities were L. variabilis (DeA = 2.568 ind./ha and DeR = 24.21%), T. pulchra (DeA = 1,360 ind./ha and DeR = 12.82%), M. cinnamomifolia (DeA = 1,088 ind./ha and DeA = 10.26%) and H. alchoneoides (DeA = 408 ind./ha and DeA = 3.85%). A2 has a forest with more complex structure showed similar flora to four studies conducted in regions of the Ribeira Valley and Santos Lowland, and A1 showed low similarity. In A1 pioneer species stood out in the structure and A2 the role of species of different successional groups was more balanced. The vegetation component sampled at A1 presented H\' = 3,330 nat. ind-1 and J\' = 0,666 and A2 H\' = 3,919 nat. ind-1 and J\' = 0.761. Natural regeneration has been shown to promote the eradication of 95.45 to 100% of the banana trees in A1 while in A2 after 33 years, any remaining banana was observed.

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