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This dissertation examines nursery/garden centre compliance with Invasive Alien Plant (IAPs) legislation in eThekwini and uMsunduzi, South Africa. Despite South African governmental programmes, an apparent lack of public awareness regarding IAPs persists. The cost to clear IAPs in South Africa is estimated to be 12 billion Rand over 20 years. Nurseries/garden centres should be able to increase customer awareness of IAPs. However, Government regulation/instruction of nurseries/garden centres seems inadequate. A mixed methods approach involving quantitative and qualitative analyses of questionnaires, observations and interviews was used in this study. There was little evidence that nurseries/garden centres stocked/sold CARA plants. However, they were stocking/selling NEMBA plants in spite of knowing CARA, NEMBA and indigenous alternatives. There is little interaction with relevant government/industry programmes. It is recommended that the Department of Environmental Affairs institute a IAPs Advisory Committee to see to the dissemination and provision of relevant information and training concerning IAPs to the industry.

Invasive species are an increasing problem worldwide, threatening indigenous communities and species. In a world where people travel and trade a lot in a global market, many organisms are transported to new parts of the world where they have never existed before. Most do not survive in the new environment but die, but some thrive and thrive. When such species are established and multiply in places outside their natural range, it can be followed by negative consequences for species that have existed there for a long time - so-called indigenous species. Then the new species are often called alien invasive species. An example of this is the beautiful and colourful plant flower lupin (Lupinus polyphyllus)that people on their travels brought with them from North America, among other things, Europe. Global warming and increased trade between countries is the main reason why foreign species are introduced to new ecosystems while climate change means that habitats can change to become more suitable for an invasive alien species. The invasive species currently causes major economic losses worldwide. Lupins, park slides, and giant sheds are examples of invasive plants that have been introduced in European gardens because they are beautiful and easy to care for. They are also invasive, spread aggressively and are detrimental to our nature because they penetrate our native species. To stop these invasive plants and from damaging Europe's nature, the EU countries have decided to take action against certain species. On January 1, 2015, the EU adopted a regulation on invasive alien species and how to combat it within the Union. On February 5, 2016, the Swedish Environmental Protection Agency submitted the Authority's proposal to the Swedish Government on new rules and measures on how to stop invasive harmful species. Already today, great resources are being devoted to combating invading plants such in our nature reserves. However, an early preventive or direct targeted intervention is much more cost effective than a continuous control of unwanted, invasive species with well-established populations. In order to succeed in this, we need an increased awareness of the problem of alien, invasive species among the public and decision makers, but also a sharp global analysis. Only with knowledge and continuous monitoring can we put in early action against future, aggressive invaders.

<p>Since wetlands provide many important ecosystem services, there is much interest in protecting existing wetlands and restoring degraded wetlands. Yet, degraded wetlands and restoration sites are often vulnerable to plant invasions that can hinder restoration success. Invasive plants typically reduce biodiversity and alter important ecosystem functions and services. This dissertation examines the ecological impact and management of invasive plant species during wetland restoration with a focus on three important drivers of plant community change in wetland ecosystems: disturbance, plant strategies, and environmental filters.</p><p>The investigations included in this research were conducted in a tropical dry wetland (Palo Verde Marsh, Palo Verde National Park, Costa Rica) and a temperate piedmont riparian forest (Sandy Creek, Duke Forest Stream and Wetland Assessment and Management Park, Durham, North Carolina). In these experiments, the primary species of interest are <italic>Typha domingensis</italic> Pers. (cattail; Typhaceae), <italic>Ligustrum sinense</italic> Lour. (Chinese privet; Oleaceae), <italic>Arundinaria gigantea</italic> (Walter) Muhl. (giant cane; Poaceae), and <italic>Microstegium vimineum</italic> (Trin.) A. Camus (Japanese stiltgrass; Poaceae).</p><p>The expansion of <italic>Typha</italic> into wetlands historically not dominated by cattail typically occurs in response to natural and anthropogenic perturbations. Management approaches that reduce <italic>Typha</italic> dominance, increase diversity, and restore or maintain wetland ecosystem services are of interest worldwide. The objective of the first phase of the research was to investigate a unique <italic>Typha</italic> removal method that is used in one of the most dynamic and ecologically important wetlands in Central America (Palo Verde Marsh, Palo Verde National Park, Costa Rica; a Ramsar Wetland of International Importance). Palo Verde Marsh is a tropical dry wetland with distinct and extreme wet and dry seasons; it is flooded during the wet season and has no standing water for much of the dry season. Palo Verde Marsh has historically provided important habitat for very large populations of migratory birds. However, a cattail (<italic>T. domingensis</italic>) expansion in the 1980s greatly altered the plant community and reduced avian habitat. Since then, <italic>Typha</italic> has been managed using fangueo (a Spanish word, pronounced as "fahn-gay-yo" in English). During fangueo, <italic>Typha</italic> is crushed and locally removed by a tractor with metal paddle wheels. I applied a <italic>Typha</italic> removal treatment at three levels (control, fangueo, and fangueo with fencing to exclude cattle grazing) at Palo Verde Marsh. Fangueo was applied at the beginning of the dry season resulting in a large reduction in <italic>Typha</italic> dominance (decreased aboveground biomass, ramet density, ramet height), an increase in open areas with no vegetation, and a 98 and 5-fold increase in avian density and richness, respectively. Importantly, fangueo had no apparent long-term impact on any of the soil properties measured (including bulk density). Interestingly, low soil and foliar N:P values indicate that Palo Verde Marsh and other wetlands in the region may be nitrogen limited. The fangueo process is an effective method for restricting <italic>Typha</italic> expansion and increasing plant and avian diversity. I present a model that illustrates the impact of <italic>Typha</italic> management and seasonal flooding on the plant and avian community. The technique might be adopted or modified for the restoration and management of <italic>Typha</italic> and other invasive emergent plants in other wetlands.</p><p>The second objective of this research was to better quantify the impact of the distinct and extreme anaerobic/aerobic annual cycle on the plant community in Palo Verde Marsh. Since the impact of seasonal flooding on the plant community in seasonal wetlands is often most evident after disturbance, I created gaps in the wetland vegetation via the mechanical removal of emergent vegetation and then measured plant community change using surveys of the wet and dry season standing vegetation, the seed bank, and <italic>in situ</italic> seedling recruitment. As expected, seasonal flooding acted as an environmental filter and resulted in distinct dry and wet season assemblages. The dominant plant life forms present after vegetation removal differed between seasons with emergents dominating during the dry season and floating-rooted, free-floating, and submerged species more dominant during the wet season. I identified common species that are characteristic of both seasonal assemblages and used indicator species analyses to identify species that are only likely to be found during the wet season. I also characterized the seed bank at this site; like most seasonal wetlands, plant species' resilience in this wetland were dependent upon a large and diverse seed bank which allowed many species to revegetate after disturbance and the extreme wet/dry conditions which acted like environmental filters.</p><p>In addition to the experiments conducted in Palo Verde Marsh, this dissertation also presents the results from an experiment in a temperate riparian restoration site in the North Carolina Piedmont (Sandy Creek, Duke Forest Stream and Wetland Assessment and Management Park, Durham, NC). Since riparian restoration efforts in the southeastern U.S. are often hindered by invasive non-native plants, there is much interest in approaches that can be used to reduce the impact of invasive non-native plant populations at the local level (e.g., a restoration site). In addition to the impact of non-native species-specific removal efforts, there is also much interest in the identification and assessment of native competitive-dominant plant species that can be used during riparian restoration to support important ecosystem functions and reduce non-native invasibility. <italic>Ligustrum sinense</italic> (Chinese privet) is a very common invasive non-native shrub in the region. <italic>Arundinaria gigantea</italic> (giant cane) is a native bamboo species that used to be very abundant in riparian and wetland ecosystems in the region. The objectives of this phase of the research were to: (1) measure the plant community response to removal of mature <italic>L. sinense</italic> individuals; and (2) quantify planted <italic>A. gigantea</italic> clonal expansion in the presence of other plants, particularly common non-native invasive species. Due to its potential for rapid growth and expansion, it was hypothesized that <italic>A. gigantea</italic> would be able to compete with common non-native species and reduce non-native invasibility. In a three-year split-plot experimental design, I applied a Privet-Presence treatment at two levels (Privet Present, Privet Removed) and a Cane-Planting treatment also at two levels (Cane, No Cane). The privet removal treatment resulted in 100% mortality of mature privet individuals. After privet removal, <italic>L. sinense</italic> seedlings recruited into these plots but growth has been very slow and these <italic>L. sinense</italic> individuals are not yet dominant. The privet canopy allows minimal understory plant recruitment and growth and privet removal resulted in an increase in species richness and diversity in the first year. However, in these Privet-Removed plots, a non-native invasive annual grass (<italic>Microstegium vimineum</italic>) invaded, became the most dominant species, and reduced species richness and diversity. In Privet-Removed plots, <italic>A. gigantea</italic> clonal expansion (i.e., ramet density, genet area, ramet diameter, and ramet height) was small in the first year but increased in the second and third years. Importantly, in Privet-Removed plots where <italic>A. gigantea</italic> was planted, <italic>M. vimineum</italic> cover was lower and species richness and diversity were greater; planting <italic>A. gigantea</italic> appears to have facilitated the establishment of other species and, in the process, increased diversity.</p><p>Our results emphasize several general conclusions that are applicable to other restoration efforts in other ecosystems with other plant species. First, during ecological restoration, invasive non-native plant removal alone will typically not restore native plant communities. Non-native invasive plant populations are typically very resilient to removal. Hence, long-term reductions in non-native invasibility will often require additional management efforts. For example, in the tropics my research showed the effectiveness of Fangueo for reducing <italic>Typha</italic> monocultures and increasing native plant and bird diversity. Another approach for improving ecosystems functions and reducing non-native invasibility after invasive plant removal is to carefully select and plant native species with competitive-dominant traits that will be able to compete with invading non-native species and resist invasion. Although this seemingly simple approach is often used by restoration practitioners, the results are rarely monitored and surprisingly few studies are designed to explicitly identify and investigate the performance of these important native competitive-dominant species.</p> / Dissertation

Svetimžemių augalų, gyvūnų ir kitų organizmų invazija ir jų natūralizacija dabar tapusi globalia problema, kuriai pastaraisiais dešimtmečiais skiriama daug dėmesio. Viena iš invazinių augalų rūšių Lietuvoje yra gausialapis lubinas (Lupinus polyphyllus). Ši rūšis įrašyta į Lietuvos invazinių rūšių sąrašą. Gausialapis lubinas paplitęs visoje šalyje ir toliau plinta bei skverbiasi į pievų, smėlynų, miškų ir įvairias antropogenines buveines. Darbo tikslas – įvertinti gausialapio lubino (Lupinus polyphyllus) poveikį vietiniams augalams ir jų bendrijoms Kurtuvėnų regioniniame parke. Uždaviniai: 1) nustatyti skirtingose buveinėse augančio gausialapio lubino populiacijų sudėtį pagal brandos amžiaus grupes; 2) įvertinti gausialapio lubino individų tankumą populiacijose; 3) nustatyti gausialapio lubino įtaką rūšių įvairovei skirtingose buveinėse; 4) ištirti gausialapio lubino poveikį skirtingoms vietinių augalų rūšims ir jų gausumui bendrijose. Gausialapio lubino populiacijų sudėties ir poveikio augalų bendrijoms tyrimai Kurtuvėnų regioniniame parke atlikti 2013 m. birželio 6–23 d. Tyrimams buvo pasirinktos 5 populiacijos, esančios skirtingose buveinėse. Tyrimai atlikti taikant laukelių metodą. Kiekvienoje populiacijoje vertinta po 20 tiriamųjų laukelių. Gausialapio lubino populiacijose generatyviniai individai sudaro nedidelę visų individų dalį. Populiacijose vyrauja jauni individai (juveniliniai ir imaturiniai). Tai parodo, kad populiacijos sparčiai atsinaujina ir plečiasi... [toliau žr. visą tekstą] / Immigration and naturalization of alien species of plants, animals and other organisms is a global problem and current issue of many investigations. Washington lupine (Lupinus polyphyllus) is one of invasive plant species in Lithuania which is included into the legal list of invasive species. Washington lupine is distributed throughout the whole territory of Lithuania and its further spread as well as invasion into meadow, forest and sand habitats is evident. The aim of the investigation was to reveal influence of Washington lupine on native plant species and communities in Kurtuvėnai Regional Park. Following tasks were formulated: 1) to reveal structure of Washington lupine populations; 2) to estimate density of Washington lupine in different populations; 3) to reveal influence of Washington lupine on species diversity in different habitats; 4) to investigate impact of Washington lupine on abundance of native species in invaded communities. Studies on population structure and impact on plant communities of Washington lupine conducted in Kurtuvėnai Regional Park on June 6–23, 2013. Five populations situated in different habitats were selected for investigations. Sampling plot method was applied and 20 sampling plots were investigated in each population. Generative individuals in populations of Washington lupine comprise a small part of all individuals. Young individuals (juvenile and immature) prevail in all populations and it is indication of intense rejuvenation and... [to full text]

This dissertation examines nursery/garden centre compliance with Invasive Alien Plant (IAPs) legislation in eThekwini and uMsunduzi, South Africa. Despite South African governmental programmes, an apparent lack of public awareness regarding IAPs persists. The cost to clear IAPs in South Africa is estimated to be 12 billion Rand over 20 years. Nurseries/garden centres should be able to increase customer awareness of IAPs. However, Government regulation/instruction of nurseries/garden centres seems inadequate. A mixed methods approach involving quantitative and qualitative analyses of questionnaires, observations and interviews was used in this study. There was little evidence that nurseries/garden centres stocked/sold CARA plants. However, they were stocking/selling NEMBA plants in spite of knowing CARA, NEMBA and indigenous alternatives. There is little interaction with relevant government/industry programmes. It is recommended that the Department of Environmental Affairs institute a IAPs Advisory Committee to see to the dissemination and provision of relevant information and training concerning IAPs to the industry.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O processo de introdução de espécies é reconhecido como a segunda causa mais importante de erosão da diversidade biológica em muitos ambientes no Brasil e no mundo. As espécies invasoras possuem não apenas o poder de sobrevivência e adaptação em outros ambientes, mas a capacidade de dominar a diversidade biológica nativa através da alteração das características básicas dos processos ecológicos naturais e das interações. A jaqueira, Artocarpus heterophyllus Lamarck (Moraceae), tem sua origem nas florestas tropicais da Índia, tendo sido introduzida no Brasil ainda no período Colonial e atualmente é invasora em áreas de Mata Atlântica. Este estudo fornece os primeiros dados sobre a influência da espécie exótica invasora Artocarpus heterophyllus sobre comunidades de anuros de folhiço. As amostragens foram realizadas em uma área de Mata Atlântica, no litoral sudoeste do estado do Rio de Janeiro, incluindo informações sobre riqueza de espécies, densidades específicas e parâmetros ambientais. Nosso estudo foi realizado no Parque Estadual da Ilha Grande entre janeiro de 2009 e março de 2011. Para amostrar a comunidade de anuros de folhiço usamos 154 parcelas de 5 x 5 m, sendo 77 delas em áreas com jaqueiras e 77 em áreas sem jaqueiras, totalizando 3.850 m de chão de floresta amostrados. Nós amostramos um total de 613 anuros habitando o chão da floresta, pertencentes a dez espécies: Brachycephalus didactylus; Chiasmocleis sp.; Haddadus binotatus; Ischnocnema guentheri; Ischnocnema octavioi; Ischnocnema parva; Leptodactylus marmoratus; Physalaemus signifer; Rhinnela ornata e Zachaenus parvulus. Seis das dez espécies foram comuns às áreas com e sem jaqueiras, sendo a similaridade entre as duas áreas de 60%. As áreas com jaqueiras tiveram o dobro (N = 18) de parcelas sem nenhum anfíbio. O número de anfíbios registrados nas parcelas com jaqueiras (38%) foi menor do que o encontrado nas áreas sem jaqueiras (62%). O anfíbio predominante no folhiço em ambas às condições foi Ischnocnema parva, tendo abundancia maior nas parcelas sem jaqueiras. A densidade total de anuros vivendo no chão da floresta nas áreas com jaqueiras (12,2 ind/100 m) foi menor que nas áreas sem jaqueiras (19,7 ind/100 m). Entre os parâmetros ambientais analisados os que possuíram maior influência sobre a abundância de anfíbios foram a profundidade do folhiço e o pH do solo. Os dados sugerem que a jaqueira, além de ocupar o habitat de espécies nativas, é capaz de promover alterações na estrutura desses habitats que irão intervir na fauna do local. / The process of species introduction is recognized as the second most important cause of biological diversity erosion in many environments in Brazil and worldwide. Invasive species have not only the power to survive and adapt in other environments, but also the ability to master the native biodiversity by altering the basic characteristics of natural ecological processes and interactions. The jackfruit tree, Artocarpus heterophyllus Lamarck (Moraceae), has its origin in the tropical forests of India, being introduced in Brazil during the Colonial period and is currently invading the Atlantic Forest. In this study we provide the first data about the influence of the invasive alien species Artocarpus heterophyllus on anuran communities. Samples were taken in an area of Atlantic Forest, on the Southwest coast of the State of Rio de Janeiro, and included information on species richness, density and environmental parameters. Our study was conducted at the Ilha Grande State Park, between January 2009 and March 2011. To sample the community of litter anurans we constructed 154 plots of 5 x 5 m, being 77 of them in areas with jackfruit and 77 in areas with no jackfruit, totaling 3.850m of forest floor sampled. We collected a total of 613 frogs inhabiting the forest floor, being distributed within ten species: Brachycephalus didactylus; Chiasmocleis sp.; Haddadus binotatus; Ischnocnema guentheri; Ischnocnema otavioi; Ischnocnema parva; Leptodactylus marmoratus; Physalaemus signifer; Rhinnela ornata and Zachaenus parvulus. Six of this species were common to areas with and without jackfruit, and the similarity between the two areas was 60%. Areas with jackfruit had the double (N = 18) of plots with no amphibian. The number of amphibians recorded in plots with jackfruit (38%) was lower than the number found in areas without jackfruit (62%). The predominant amphibian species in both conditions was Ischnocnema parva, which had greater abundance in plots without jackfruit. The total density of frogs living on the forest floor in areas with jackfruit (12.2 ind/100 m) was lower than in areas without jackfruit (19.7 ind/100 m). Among the environmental parameters analyzed those with greater influence on the abundance of amphibians were the depth of leaf litter and soil pH. The data suggested that the addition of jackfruit, besides occupying the habitat of native species, is able to promote changes in the structure of these habitats that may intervene in the local fauna.

Tropical habitats face a diverse range of anthropogenic threats. Two common and important threats to tropical biodiversity are invasive species and roads. Invasive plants are proposed to be a major threat to biodiversity worldwide, yet not much is known about their impacts on higher trophic levels, such as insects. Roads and other linear intrusions, such as power lines and railway tracks, are another common aspect of human disturbance in natural landscapes, including tropical forests, and are often linked to the spread of invasive plants. I studied impacts of these two important proximate drivers of habitat disturbance, namely invasive plant species and roads, on habitat use by butterflies in a tropical moist deciduous forest in Western Ghats of India. Invasive plants and roads are expected to modify micro-habitat structure, resources and other aspects of ecology of butterflies and thereby influence how they use space (i.e., micro-habitats within the larger habitat). Because systematic ecological information on tropical butterflies is comparatively limited, I adopted a multi-species approach. I examined space use responses of butterflies to a gradient of lantana cover in the forest and to a road passing through forest. The abundance of different species of butterflies in different micro-habitats was taken as a measure of habitat use. Data was collected over two seasons and at two spatial scales. The two habitat disturbances were found to influence local habitat use by butterflies. But interestingly, species appeared to respond differently, with some showing positive, others negative and some no clear association with road verge or lantana gradient. I then examined whether this variation in response could be understood in terms of species-specific functional traits. Correlating the responses of species to a habitat disturbance with functional traits may provide a way of arriving at general patterns and increase the ability of studies to predict responses. Species with similar trait values are expected to respond similarly to a habitat change driver. I measured morphological traits in 254 butterfly species from India and classified them according to their habitat preferences (based on expert opinion). I first examined relationships between morphological traits, habitat preferences and evolutionary relatedness. I then examined patterns of correlation between these traits and responses to the two habitat disturbances and found that certain traits can help predict responses. Overall, my study suggests that butterfly space use is influenced by roads and lantana, but the response varies across species. These changes in habitat use might have important population or community-level consequences, such as population declines and shifts in community structure and composition; these need to be further examined.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O processo de introdução de espécies é reconhecido como a segunda causa mais importante de erosão da diversidade biológica em muitos ambientes no Brasil e no mundo. As espécies invasoras possuem não apenas o poder de sobrevivência e adaptação em outros ambientes, mas a capacidade de dominar a diversidade biológica nativa através da alteração das características básicas dos processos ecológicos naturais e das interações. A jaqueira, Artocarpus heterophyllus Lamarck (Moraceae), tem sua origem nas florestas tropicais da Índia, tendo sido introduzida no Brasil ainda no período Colonial e atualmente é invasora em áreas de Mata Atlântica. Este estudo fornece os primeiros dados sobre a influência da espécie exótica invasora Artocarpus heterophyllus sobre comunidades de anuros de folhiço. As amostragens foram realizadas em uma área de Mata Atlântica, no litoral sudoeste do estado do Rio de Janeiro, incluindo informações sobre riqueza de espécies, densidades específicas e parâmetros ambientais. Nosso estudo foi realizado no Parque Estadual da Ilha Grande entre janeiro de 2009 e março de 2011. Para amostrar a comunidade de anuros de folhiço usamos 154 parcelas de 5 x 5 m, sendo 77 delas em áreas com jaqueiras e 77 em áreas sem jaqueiras, totalizando 3.850 m de chão de floresta amostrados. Nós amostramos um total de 613 anuros habitando o chão da floresta, pertencentes a dez espécies: Brachycephalus didactylus; Chiasmocleis sp.; Haddadus binotatus; Ischnocnema guentheri; Ischnocnema octavioi; Ischnocnema parva; Leptodactylus marmoratus; Physalaemus signifer; Rhinnela ornata e Zachaenus parvulus. Seis das dez espécies foram comuns às áreas com e sem jaqueiras, sendo a similaridade entre as duas áreas de 60%. As áreas com jaqueiras tiveram o dobro (N = 18) de parcelas sem nenhum anfíbio. O número de anfíbios registrados nas parcelas com jaqueiras (38%) foi menor do que o encontrado nas áreas sem jaqueiras (62%). O anfíbio predominante no folhiço em ambas às condições foi Ischnocnema parva, tendo abundancia maior nas parcelas sem jaqueiras. A densidade total de anuros vivendo no chão da floresta nas áreas com jaqueiras (12,2 ind/100 m) foi menor que nas áreas sem jaqueiras (19,7 ind/100 m). Entre os parâmetros ambientais analisados os que possuíram maior influência sobre a abundância de anfíbios foram a profundidade do folhiço e o pH do solo. Os dados sugerem que a jaqueira, além de ocupar o habitat de espécies nativas, é capaz de promover alterações na estrutura desses habitats que irão intervir na fauna do local. / The process of species introduction is recognized as the second most important cause of biological diversity erosion in many environments in Brazil and worldwide. Invasive species have not only the power to survive and adapt in other environments, but also the ability to master the native biodiversity by altering the basic characteristics of natural ecological processes and interactions. The jackfruit tree, Artocarpus heterophyllus Lamarck (Moraceae), has its origin in the tropical forests of India, being introduced in Brazil during the Colonial period and is currently invading the Atlantic Forest. In this study we provide the first data about the influence of the invasive alien species Artocarpus heterophyllus on anuran communities. Samples were taken in an area of Atlantic Forest, on the Southwest coast of the State of Rio de Janeiro, and included information on species richness, density and environmental parameters. Our study was conducted at the Ilha Grande State Park, between January 2009 and March 2011. To sample the community of litter anurans we constructed 154 plots of 5 x 5 m, being 77 of them in areas with jackfruit and 77 in areas with no jackfruit, totaling 3.850m of forest floor sampled. We collected a total of 613 frogs inhabiting the forest floor, being distributed within ten species: Brachycephalus didactylus; Chiasmocleis sp.; Haddadus binotatus; Ischnocnema guentheri; Ischnocnema otavioi; Ischnocnema parva; Leptodactylus marmoratus; Physalaemus signifer; Rhinnela ornata and Zachaenus parvulus. Six of this species were common to areas with and without jackfruit, and the similarity between the two areas was 60%. Areas with jackfruit had the double (N = 18) of plots with no amphibian. The number of amphibians recorded in plots with jackfruit (38%) was lower than the number found in areas without jackfruit (62%). The predominant amphibian species in both conditions was Ischnocnema parva, which had greater abundance in plots without jackfruit. The total density of frogs living on the forest floor in areas with jackfruit (12.2 ind/100 m) was lower than in areas without jackfruit (19.7 ind/100 m). Among the environmental parameters analyzed those with greater influence on the abundance of amphibians were the depth of leaf litter and soil pH. The data suggested that the addition of jackfruit, besides occupying the habitat of native species, is able to promote changes in the structure of these habitats that may intervene in the local fauna.

Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-06-02T13:20:51Z No. of bitstreams: 1 Patricia Barbosa Lima.pdf: 4109614 bytes, checksum: 3b7b42d45a4e5399c06e4dca0fa7137f (MD5) / Made available in DSpace on 2016-06-02T13:20:51Z (GMT). No. of bitstreams: 1 Patricia Barbosa Lima.pdf: 4109614 bytes, checksum: 3b7b42d45a4e5399c06e4dca0fa7137f (MD5) Previous issue date: 2016-02-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Secondary forest areas in different successional stages are predominantly found in tropical rainforest areas, and can help with biodiversity maintenance. These forests show gradual changes in biotic and abiotic environment throughout the forest succession. The successional trajectory is well described for woody flora. Nevertheless, studies on herbaceous plants are still lagging. This study was divided into two manuscripts, whose objectives were to: 1) analyze herbaceous assembly in a 30 years chronosequence of sugar cane abandonment, and compare theses assemblade to mature forest sites, also considering environmental factors (chronosequence age, surrounding forest cover, understory light, and soil characteristics) that drive the herbs responses; and 2) understand how aliens herbaceous affect richness, and native forest herbs diversity of this chronosequence. In order to understand this, one sugar cane abandoned chronosequence was selected, containing 15 secondary forest sites (FS) (ages varying from 4 up to 30 years of abandonment), and 15 areas of mature forest (FM) in the Corredor Ecológico Pacatuba-Gargaú landscape, located inside of Paraíba Atlantic forest. In each site were established nine plots of 5x5m, in a total of 270 plots, which all herbs were registered. The plants were identified and posteriorly classified regarding their geographic origin. An NMDS was performed in order to verify difference in the floristic composition among FS and FM sites, as well as, an analysis of indicator species of those environments was performed. Generalized Linear Models (GLMs) were used to test: the impact of age areas, soil characteristics, availability of light, and surrounding forest cover on the structural characteristics of herbs in FS; and the impact of the more representative aliens herbs on native flora of FS. In a total, 42,966 individuals were registered (of this total 32,915 and 10,615 native and alien individuals, respectively), in 67 species (59 natives; 6 aliens herbs; 2 morphospecies; 66% and 18% of exclusive species in FS and FM, respectively). The density and the diversity of the herbs were significantly higher in FS than in FM, while the richness was lower in FM and the equability did not exhibit significantive difference. There was more proportion of native herbs than aliens herbs in both habitats. The floristic composition was distinct between FS and FM, also were observed 21 and 11 indicatives species of FS and FM, respectively. The sites age was positively related to richness and species diversity; however, negatively related to the herbs density. Successional progress influenced positively native richness throughout the chronosequence, and minimized negative impact of the only two invasive especies Digitaria insularis and Megathyrsus maximum on native’s species. Surrounding forest cover was also one of the mainly variants that negatively influenced richness and herbs density of the studied landscape. Finally, this study shows that despite the invasive species presence on the sugar cane abandoned chronosequence, the landscape Corredor Ecológico Pacatuba-Gargaú exhibits a dense, diverse, and rich flora of herbs (natives and alien), that are in agreement to the Intermediate Disturbance Hypothesis, and it is favored by the increment of biotic resistance associated to environmental changes along the successional progress. / Áreas de floresta secundária em diferentes estádios sucessionais predominam na região tropical úmida e podem auxiliar na manutenção da biodiversidade. Estas florestas apresentam uma gradativa mudança nos meios biótico e abiótico no decorrer da sucessão florestal. A trajetória sucessional está bem descrita para a flora lenhosa, todavia estudos sobre as plantas herbáceas continuam defasados. Este trabalho foi dividido em dois manuscritos, que tiveram os objetivos de: 1) analisar a assembleia de herbáceas em uma cronossequência de 30 anos de abandono canavieiro, e comparar essas assembleias com as de sítios de florestas maduras, considerando também fatores ambientais (idade da cronossequência, cobertura florestal circundante, luminosidade no sub-bosque e características edáficas) que direcionam as respostas das ervas; e 2) compreender como herbáceas exóticas afetam a riqueza e a densidade de ervas florestais nativas dessa cronossequência. Para isso, foram selecionadas uma cronossequência de canaviais abandonados contendo 15 sítios de florestas secundárias (FS) (com idades variando de 4 até 30 anos de abandono) e 15 áreas de floresta madura (FM) na paisagem do corredor Ecológico Pacatuba-Gargaú localizada dentro da floresta Atlântica da Paraíba. Em cada sítio foram estabelecidas nove parcelas de 5x5m, totalizando 270 parcelas, nas quais todas as ervas foram registradas. As plantas foram identificadas e posteriormente classificadas quanto à origem geográfica. Um NMDS foi realizado para verificar a diferença na composição florística entre os sítios de FS e FM, bem como, foi realizada uma análise de espécies indicadoras destes ambientes. Modelos Lineares Generalizados (GLMs) foram usados para testar: 1) o impacto da idade das áreas, das características de solo, da disponibilidade de luz e da cobertura florestal circundante sobre as características estruturais das ervas em FS; e 2) o impacto das ervas exóticas mais representativas sobre a flora nativas de FS. Registraram-se 42.966 indivíduos no total (sendo 32.915 e 10.615 indivíduos nativos e exóticos, respectivamente), em 67 espécies (59 nativas; seis exóticas; duas morfoespécies; 66% e 18% de espécies exclusivas em FS e FM, respectivamente). A densidade e a diversidade de ervas foram significativamente maiores em FS do que em FM, enquanto que a riqueza foi menor em FM e a equitabilidade não exibiu diferença significativa. Houve maior proporção de ervas nativas do que ervas exóticas em ambos os hábitats. A composição florística foi distinta entre FS e FM, e foram observados 21 e 11 espécies indicadoras de FS e FM, respectivamente. A idade dos sítios foi positivamente relacionada à riqueza e diversidade de espécies, mas negativamente relacionada com a densidade de ervas. O avanço na sucessão influenciou positivamente a riqueza de nativas ao longo da cronossequência e minimizou o impacto negativo das únicas espécies invasoras Digitaria insularis e Megathyrsus maximum sobre as nativas. E a cobertura florestal circundante foi também uma das principais variáveis que influenciou negativamente a riqueza e densidade de ervas da paisagem estudada. Por fim, este estudo mostrou que apesar de possuir espécies invasoras na cronossequência de abandono canavieiro, a paisagem do Corredor Ecológico Pacatuba-Gargaú exibe uma rica, densa e diversa flora de ervas (nativas e exóticas), que segue os pressupostos da Hipótese do Distúrbio Intermediário e que é favorecida pelo incremento da resistência biótica associada às mudanças ambientais ao longo do avanço sucessional.