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Planet Earth is undergoing a rapid rate of ecosystem conversion and degradation and one of the major challenges of current environmental science is to contribute to the management and conservation of biodiversity through the development of tools for assessing environmental change. The main goal of this doctoral dissertation is to contribute to the scientific literature on remote sensing tools for monitoring tropical dry forests, which is one of most important global change frontiers. This thesis is composed of five chapters which have the goals of covering the following specific goals: 1) To estimate the extent and geographic distribution of the neotropical dry forest. 2) To evaluate the potential use of satellite-detected fires as deforestation predictors in tropical dry forest and 3) To evaluate the potential of remote sensing techniques to detect edge effects in tropical dry forest. Before assessing the main goals of the thesis, in chapter two, Integrating Remote Sensing and Biodiversity research, we stress out the necessity of integrated assessments using multiple spatial and spectral resolution sensors over a wide array of ecosystems in order to find relevant ecosystem properties that would be sensitive to species richness. Chapter three, Extent and Conservation of tropical dry forests in the Americas, describes a regional scale mapping effort using coarse-scale imagery (MODIS 500-m) of the extent and geographical distribution of tropical dry forests that introduces several innovations to previous assessments. Based on these techniques, the total current extent of tropical dry forest in the Americas is 519,597 Km2. I also found that 66% of the ecosystem has been already converted to other land uses while only 4.5 % of is under protected areas. Chapter four, MODIS Active fires and deforestation in tropical dry forest landscapes, we show correlations patterns between the number of MODIS Active Fires and forest cover change in four tropical dry forest landscapes in Latin America. At the Santa Cruz site (Bolivia), correlations were strong and significant while at Chamela Site (Mexico) and the Mata Seca site (Brazil) correlations were moderate but significant as well. In the Machango site (Venezuela), active fires showed no correlation to deforestation events. In general, our findings show that fires detected by the MODIS sensor may be used as predictors of deforestation in tropical dry forest ecosystems. Chapter five, Edge influence on canopy openness and understory microclimate in two Neotropical dry forest fragments, addresses one of the most characteristic features of fragmented tropical forests: the increase in disturbance near the edges of the fragment or what is known as edge effects. Results in gap fraction and Fraction of Intercepted Photosynthetically Active Radiation (FiPAR) show that edge influence at tropical dry forest sites extend to at least 300-m. Finally, Chapter Six, Remote sensing of edge effects in dry forest fragments using CHRIS/Proba Imagery, shows an assessment of changes in the fraction of intercepted photosynthetically active radiation (FiPAR) across four edge-to-interior transects in tropical dry forests fragments and their correlation to spectral vegetation indices (SVIs) computed from the hyperspectral and multiangular CHRIS sensor on board the Proba platform. Results show that the use of spectral vegetation indices for identifying and quantifying edge effects in tropical forests have the potential to improve modeling of forest disturbance in fragmented landscapes. The work contained in these five chapters address issues that are critical to the advancement of tropical dry forest monitoring. These studies contribute to the current scientific literature on the use and application of optical remote sensing tools, not only applicable in tropical dry forests, but for tropical forest conservation at the continental, regional and local level.

Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-05-24T13:57:47Z No. of bitstreams: 1 Pedro Arthur do Nascimento Oliveira.pdf: 826797 bytes, checksum: e6737ad50f7ee0d7e128d43429c4ddcd (MD5) / Made available in DSpace on 2016-05-24T13:57:47Z (GMT). No. of bitstreams: 1 Pedro Arthur do Nascimento Oliveira.pdf: 826797 bytes, checksum: e6737ad50f7ee0d7e128d43429c4ddcd (MD5) Previous issue date: 2016-02-22 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The tropical dry forests have suffered over time with the agricultural development, the extent of human occupation and extraction of natural resources. Two ecological processes have been studied in the work related to natural regeneration: the soil seed bank and regenerating assembly. However, few studies associate the seed bank with regenerating assembly in areas that have suffered human disturbance, and deforestation and forest fires, the main factors that alter the composition and floristic richness and seed density of the seed bank and the assembly of regenerating beyond the age of the forest. This study aimed to test the following hypotheses: 1) the seed bank has a higher species richness than the meeting of regenerating and different histories of human activities intensify this difference; 2) the seed bank has a higher density than the meeting of regenerating and different histories of human activities intensify this difference; 3) the floristic composition of the seed bank is different from regenerating assembly and different histories of human activities intensify this difference. The study was conducted in an area of seasonally dry forest, caatinga, located in Agricultural Research Institute (IPA) in Caruaru, Pernambuco, in a fragment of mature forest and forest Young. They were considered belonging to regenerating assembly herbaceous species and seedlings and juveniles of woody species, which had up to 1 m tall. For sampling regenerating assembly were randomly 40 plots of 1x2 m, 20 in the mature forest and 20 in young forest. To the seed bank were collected 20 soil samples in mature forest and 20 in young forest, next to the plots established for the census of regenerating assembly. The collection of soil was made through installments made with galvanized sheet 20 x 20 cm and 5 cm deep and including litter. In this study, the young and mature forests, there was no significant difference in species richness between the seed bank and the assembly of regenerating, but the floristic composition is not the same. human actions intensify the difference in the density of seed bank and assembly of regenerating between young and mature forests. / As florestas tropicais secas vêm sofrendo ao longo do tempo com o desenvolvimento agrícola, a extensão da ocupação humana e extração de recursos naturais. Dois processos ecológicos vêm sido estudados nos trabalhos referentes a regeneração natural: o banco de sementes do solo e a assembleia de regenerantes. Porém, poucos trabalhos associam o banco de sementes com a assembleia de regenerantes em áreas que sofreram antropização, sendo o desmatamento e queimadas, os principais fatores que alteram a composição e riqueza florística e a densidade de sementes do banco de sementes e da assembleia de regenerantes, além da idade da floresta. Este estudo pretendeu testar as seguintes hipóteses: 1) o banco de sementes possui uma maior riqueza de espécies do que a assembleia de regenerantes e ações antrópicas intensificam esta diferença; 2) o banco de sementes possui uma maior densidade do que a assembleia de regenerantes e ações antrópicas intensificam esta diferença; 3) a composição florística do banco de sementes é diferente da assembleia de regenerantes e ações antrópicas intensificam esta diferença. O estudo foi desenvolvido em uma área de floresta sazonalmente seca, denominada caatinga, localizada no Instituto de Pesquisa Agropecuária (IPA) em Caruaru, Pernambuco, em um fragmento de Floresta Madura e Floresta Jovem. Foram consideradas pertencentes à assembleia de regenerantes as espécies herbáceas e plântulas e juvenis de espécies lenhosas, que possuíam até 1 m de altura. Para a amostragem da assembleia de regenerantes foram instaladas aleatoriamente 40 parcelas de 1x2 m, sendo 20 na floresta madura e 20 na floresta jovem. Para o banco de sementes foram coletadas 20 amostras de solo na floresta madura e 20 na floresta jovem, ao lado das parcelas instaladas para o censo da assembléia de regenerantes. A coleta do solo foi feita através de parcelas confeccionadas com chapa galvanizada de 20 x 20 cm, com 5 cm de profundidade e incluindo a serrapilheira. Neste estudo, nas florestas jovem e madura, não houve diferença significativa na riqueza de espécies entre o banco de sementes e a assembleia de regenerantes, mas a composição florística não é a mesma. Ações antrópicas intensificam a diferença na densidade do banco de sementes e assembleia de regenerantes entre florestas jovem e madura.

Our knowledge of whether hurricanes cause lasting changes in forest composition and the patterns and role of fire in Caribbean dry forests are lacking. This project combines paleoecological and paleotempestological methods to document the disturbance and environmental history of the last 1000 yrs at Laguna Alejandro, situated in the lowland dry forests of arid SW Dominican Republic. I analyzed multiple proxy data sources of a 160 cm coastal lagoon sediment profile. High-resolution (1 cm) sampling for loss-on-ignition and magnetic susceptibility indicated multiple erosion and hurricane events, including a hurricane ~996 cal YBP, and several erosion events and hurricanes between ~321 cal YBP and present day. Pollen analysis documented 32 plant families with most levels dominated by pollen of Fabaceae (legumes), the Urticales order, and Cyperaceae (sedges), though families of upland and montane vegetation are also present ~510-996 cal YBP. All pollen slides contained microscopic charcoal indicating the occurrence of regional or extra-local fires over the last ~1000 yrs. Local fires, as indicated by macroscopic charcoal, occurred before ~434 cal YBP and may be tied to hurricanes, increased moisture in the region (thereby increased fuel and ignition chances), or prehistoric human activities. Pollen spectra representing periods before and after disturbance events were similar and may support the idea of forest resilience, but more samples are needed. Multiple erosion events between ~294 cal YBP and present may be tied to hurricanes or tropical storms and increasing late-Holocene aridity in the region as documented by several studies from the Caribbean. / Master of Science

As matas secas representam um ambiente extremamente ameaçado, sendo considerado um dos mais ameaçados do mundo. Um fato que contribui para esta ameaça além da intensa pressão antrópica, é a falta de conhecimento, sem o qual é impossível se realizar ações para sua conservação. Na região do Rio Paranã as matas secas revelam espécies compartilhadas com a caatinga, concordando com a idéia de uma ocorrência mais ampla deste habitat no passado. Na região do Peruaçu, dentre as espécies que ocorrem nas matas secas e em suas outras fisionomias, como o carrasco, existem espécies compartilhadas com a Mata Atlântica (Enyalius pictus), e espécies aparentemente associadas à estes habitats secos e densos, na região do planalto dos gerais (Stenocercus quinarius). Na região do Peruaçu, estas espécies apresentaram uma estreita associação com estes habitats, assim como ocorre em outras localidades. Estas características de sua história natural, determinam ocorrências local e regionalmente, e permitem dispersão durante climas favoráveis à expansão de seu habitat e isolamento durante sua fragmentação. E. pictus, pode se dispersar entre as matas secas e úmidas, atingindo a região do Peruaçu, o que concorda com a idéia de uma maior abrangência das matas durante momentos do passado, mas aponta uma conexão com a Mata Atlântica e não Caatinga. Esta maior abrangência também é observado na distribuição de S. quinarius restrito hoje à fragmentos isolados de vegetação densa ao longo do Planalto dos Gerais. Os resultados obtidos demonstram extrema necessidade de levantamentos de espécies detalhados e registros de sua história natural nas áreas de mata seca, para melhorar nosso conhecimento sobre este bioma, ajudar no entendimento da história biogeográfica deste ecossistema, e a definir áreas prioritárias à conservação dentro de sua distribuição. / Dry Forests are environments extremely endangered, considered one of the most en-dangered ecosystems of the world. The lack of knowledge, together with intense anth-ropic pressure, contributes to this threat, and without this knowledge it is impossible to perform conservational actions to protect this habitat. At Paranã region dry forests revealed species shared with Caatinga, what is in agreement with the hypothesis of broader occurrence in the past. At Peruaçu region, among those species found at the dry forests and at its physiognomies, such as carrasco, there are species shared with the Atlantic Forest (Enyalius pictus) and those associated with this dry habitats from Planalto dos Gerais (Stenocercus quinarius). At Peruaçu region these species had a strong association with these habitats, as they show at other localities. These natural history features determine its occurrence locally as well as regionally, which results in dispersions during suitable climatic conditions for habitat expansion and isolation dur-ing habitat fragmentation. Therefore E. pictus could disperse between dry and wet forests, reaching Peruaçu region, also agreeing with the hypothesis of broader occur-rence of dry forests in the past, however indicated a connection with Atlantic Forest and not with Caatinga. This wider occurrence in the past is also observed in the distri-butional range of S. quinarius restricted today to small isolated fragments of denser vegetation along Planalto dos Gerais. These results indicate an extremely necessity for more species inventories, and records of their natural history associated with dry for-est, to improve our knowledge on it, to help the understanding of its biogeographical history and delineate priority areas for conservation within its distributional range.

Climate models predict changes to the frequency and intensity of extreme events, with large effects on tropical forests likely. Predicting these impacts requires understanding how landscape configuration and land-use change influence the susceptibility of forests to disturbances such as wind, drought, and fire. This is important because most tropical forests are regenerating from anthropogenic disturbance, and are located in landscape mosaics of forest, agriculture, and other land use. This dissertation consists of four chapters that combine remote sensing and field data to examine causes and consequences of disturbance and land-use change in tropical second-growth forests. In Chapter 1, I use satellite data to identify factors associated with permanence of second-growth forest, and assess how estimates of carbon sequestration vary under different assumptions about second-growth forest permanence. I show that most second-growth forest is cleared when young, limiting carbon sequestration. In Chapter 2, I combine data from weather stations, remote sensing, and landowner surveys to model fire activity on 732 farms in the study area over ten years. The relative importance of these factors differs across scales and depending on the metric of fire activity being considered, illustrating how implications for fire prevention and mitigation can be different depending on the metric considered. Chapter 3 combines Landsat imagery and field data to map wind damage from a severe convective storm, providing strong empirical evidence that vulnerability to wind disturbance is elevated in tropical forest fragments. Finally, in Chapter 4 I integrate annual forest census data with LiDAR-derived topography metrics and tree functional traits in a hierarchical Bayesian modeling framework to explore how drought, topography, and neighborhood crowding affect tree growth, and how functional traits modulate those effects. The results from these studies demonstrate innovative approaches to understanding spatial variation in forest vulnerability to disturbance at multiple scales, and the results have implications for managing forests in a changing climate.

Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2018-05-23T13:33:44Z No. of bitstreams: 1 PDF - Carolline Barros Cavalcante.pdf: 13868183 bytes, checksum: 58630d1453863a2b482f4307d4564397 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2018-05-23T16:50:50Z (GMT) No. of bitstreams: 1 PDF - Carolline Barros Cavalcante.pdf: 13868183 bytes, checksum: 58630d1453863a2b482f4307d4564397 (MD5) / Made available in DSpace on 2018-05-23T16:50:50Z (GMT). No. of bitstreams: 1 PDF - Carolline Barros Cavalcante.pdf: 13868183 bytes, checksum: 58630d1453863a2b482f4307d4564397 (MD5) Previous issue date: 2014-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The crown architecture is influenced by genetic and environmental factors, which are intermediated by plant hormones. In order to avoid radiation excess and water loss through transpiration, the species from arid lands such as Caatinga developed survival strategies. In Caatinga lands, the species were grouped according to their leaf phenology and it’s expected that the different phenologic patterns be related to the morphologic characteristics of the plant, including its crown. In this case, this study aimed to characterize the crown architecture of groups having different leaf phenologies from Caatinga and understand the existing relations. Nine crown species were represented, being three evergreen, three 2- to 3-month deciduous and three 4- to 6-month, and for each species three individuals were analyzed, totaling up 27. For each individual, it was accounted the number of connectors, regular, final and emission nodes, besides the distances between the different kinds of nodes. The results showed that among the analyzed groups, the greatest averages to the number of nodes and connectors were found in the 2- to 3-month-old deciduous group, followed by the evergreen group, and finally the 4- to 6-month-old deciduous group. What concerns the distances, only the distance between the final adjoining nodes differed among the groups, in a way that the evergreen trees showed the lowest average. The less segmented deciduous canopies of 4-6 months facilitate the quick distribution of resources throughout the plant, while canopies more segmented, as 2-3 months avoid self-shading of leaves along the branches. Evergreen species showed complexity of canopy reduced with self-shading avoiding excessive water loss, indicating a relationship between leaf phenology and canopy architecture in species of the Caatinga. / A arquitetura copa é influenciada por fatores genéticos e ambientais, que são intermediados por hormônios vegetais. Para evitar o excesso de radiação e a perda de água por transpiração, as espécies de ambientes áridos como a Caatinga desenvolveram estratégias de sobrevivência. Na Caatinga, as espécies foram agrupadas de acordo com a sua fenologia foliar e espera-se que os diferentes padrões fenológicos estejam relacionados às características morfológicas da planta, inclusive de sua copa. Sendo assim, objetivo deste estudo foi caracterizar a arquitetura da copa de grupos com diferentes fenologias foliares da Caatinga e compreender as relações existentes. Foram representadas as copas nove espécies, sendo três perenifólias, três decíduas de 2-3 meses e três decíduas de 4-6 meses e para cada espécie foram analisados três indivíduos, totalizando 27. Para cada indivíduo foi contabilizado o número de conectores, nós regulares, nós finais e nós de emissão, além das distâncias entre os diferentes tipos de nós. Os resultados mostraram que entre os grupos analisados, as maiores médias para o número de nós e conectores foram apresentadas pelo grupo das decíduas de 2-3 meses, seguido pelo grupo das perenifólias e por fim, pelo grupo das decíduas de 4-6 meses. Para as distâncias, apenas a distância entre nós finais vizinhos diferiu entre os grupos, de modo que o grupo das perenifólias apresentou a menor média. As copas menos segmentadas das decíduas de 4-6 meses facilitam a distribuição de recursos por toda a planta de forma rápida, enquanto que copas mais segmentadas, como das decíduas de 2-3 meses evitam o autosombreamento das folhas ao longo dos ramos. Espécies perenifólias apresentaram complexidade de copa reduzida, com autosombreamtento evitando a perda excessiva de água, evidenciando uma relação entre a fenologia foliar e a arquitetura da copa em espécies da Caatinga.

As matas secas representam um ambiente extremamente ameaçado, sendo considerado um dos mais ameaçados do mundo. Um fato que contribui para esta ameaça além da intensa pressão antrópica, é a falta de conhecimento, sem o qual é impossível se realizar ações para sua conservação. Na região do Rio Paranã as matas secas revelam espécies compartilhadas com a caatinga, concordando com a idéia de uma ocorrência mais ampla deste habitat no passado. Na região do Peruaçu, dentre as espécies que ocorrem nas matas secas e em suas outras fisionomias, como o carrasco, existem espécies compartilhadas com a Mata Atlântica (Enyalius pictus), e espécies aparentemente associadas à estes habitats secos e densos, na região do planalto dos gerais (Stenocercus quinarius). Na região do Peruaçu, estas espécies apresentaram uma estreita associação com estes habitats, assim como ocorre em outras localidades. Estas características de sua história natural, determinam ocorrências local e regionalmente, e permitem dispersão durante climas favoráveis à expansão de seu habitat e isolamento durante sua fragmentação. E. pictus, pode se dispersar entre as matas secas e úmidas, atingindo a região do Peruaçu, o que concorda com a idéia de uma maior abrangência das matas durante momentos do passado, mas aponta uma conexão com a Mata Atlântica e não Caatinga. Esta maior abrangência também é observado na distribuição de S. quinarius restrito hoje à fragmentos isolados de vegetação densa ao longo do Planalto dos Gerais. Os resultados obtidos demonstram extrema necessidade de levantamentos de espécies detalhados e registros de sua história natural nas áreas de mata seca, para melhorar nosso conhecimento sobre este bioma, ajudar no entendimento da história biogeográfica deste ecossistema, e a definir áreas prioritárias à conservação dentro de sua distribuição. / Dry Forests are environments extremely endangered, considered one of the most en-dangered ecosystems of the world. The lack of knowledge, together with intense anth-ropic pressure, contributes to this threat, and without this knowledge it is impossible to perform conservational actions to protect this habitat. At Paranã region dry forests revealed species shared with Caatinga, what is in agreement with the hypothesis of broader occurrence in the past. At Peruaçu region, among those species found at the dry forests and at its physiognomies, such as carrasco, there are species shared with the Atlantic Forest (Enyalius pictus) and those associated with this dry habitats from Planalto dos Gerais (Stenocercus quinarius). At Peruaçu region these species had a strong association with these habitats, as they show at other localities. These natural history features determine its occurrence locally as well as regionally, which results in dispersions during suitable climatic conditions for habitat expansion and isolation dur-ing habitat fragmentation. Therefore E. pictus could disperse between dry and wet forests, reaching Peruaçu region, also agreeing with the hypothesis of broader occur-rence of dry forests in the past, however indicated a connection with Atlantic Forest and not with Caatinga. This wider occurrence in the past is also observed in the distri-butional range of S. quinarius restricted today to small isolated fragments of denser vegetation along Planalto dos Gerais. These results indicate an extremely necessity for more species inventories, and records of their natural history associated with dry for-est, to improve our knowledge on it, to help the understanding of its biogeographical history and delineate priority areas for conservation within its distributional range.

Over the last 2000 years, climatic and anthropogenic factors have influenced vegetation in Madagascar, but the contribution of these two factors has been the subject of intense debate, a debate hampered by the scarcity of palaeoecological studies on the island. Southwest Madagascar is semi-arid and comprises fragmented tropical dry forests where human subsistence strategies are diverse. Therefore, it provides a perfect setting to generate new palaeoecological records and investigate vegetation response to changes in human land-use and rainfall variability. The aim of this thesis is to understand how and when land-use changed, and rainfall variability impacted the landscape in the southwest region, using dendroclimatological and palaeoecological approaches. Carbon isotopes in the rings of four baobab trees (Adansonia spp.), were compared with pre-existing palaeoclimate data to produce rainfall records for the past 1700 years. Pollen, carbon isotopes, and charcoal in sediment cores from two lakes namely Lake Longiza and Lake Tsizavatsy (located in the northern and southern sites respectively in southwest Madagascar) were analysed to produce vegetation and fire records during the late Holocene in the region. Combination of the four baobab isotope records yields a new 700-year record for the southwest, which suggests an aridity trend over time, associated with a long-term reduction and increase in the duration of wet and dry periods respectively. Drying was more pronounced for the southern site than the northern site. A comparison with a high-resolution record from the northwest region allowed the rainfall of the southwest to be extended back to the last 1700 years as follows: from AD 300-500, the southwest region experienced a dry period which was followed by a wet period until AD 1000. Subsequently, there was a dry period from AD 1000-1250, followed by a wet period in the southwest. The period from AD 1300-1400 represented the wettest period in the record, followed by a decreasing wet period until AD 1600. The period between AD 1600 and 1800 represented the driest period, peaking around AD 1700. This was followed by a relatively wet period of about 50 years and another 100-year dry period. The last period assessed, from AD 1985 to 2000, was a relatively wet period. Such variability of the rainfall might have affected ecosystems and human land-use in the region. The tropical dry forest biome of southwest Madagascar has taxa from the dry forest, riparian forest and savanna woodland in the pollen records of both sites. In the core from the northern site (Lake Longiza), the pollen record suggests a heterogeneous mosaic of dry forest and riparian forest that was present over the last 2400 years. In the earliest part of the record, the community was dominated by trees from both the dry forest and riparian ecosystems. The onset of changes was recorded around AD 420, with a decrease in dry forest and riparian trees and an increase in grasses and xerophytics, possibly driven by dry conditions. This was followed by a short recovery of trees and C3 plants around AD 870 punctuated by a decrease in dry forest taxa around AD 980, possibly associated with the suggested expansion of pastoralism. After this period, the landscape became more open and grassier, as indicated by the dominance of C4 plants in the stable isotope record. Similar patterns of change in the pollen record, with a further increase in grasses and pioneer taxa, were recorded around AD 1900. Charcoal influx also started to increase drastically at this time, suggesting fire and forest clearance associated with a shift to agriculture. These large shifts in human land-use (probably a combination of both pastoralism and agriculture) coincided with the decline of floral diversity of the landscape, as indicated by pollen rarefaction. However, the diversity of the floral community gradually recovered, because of the persistent heterogeneity of the landscape. The core from the southern site (Lake Tsizavatsy) had a basal date of approximately 700 years BP but presented a hiatus of about 500 years from AD 1420-1910. The preceding period of AD 1300-1420 was marked by a decrease in the abundance of trees during the wettest period in the region, which was most likely because of human activities (foraging and pastoralism), as inferred by the increase in charcoal influx and pioneer taxa. During the second period, from AD 1910- 2010, there was an increase in xerophytic taxa, which suggests a long dry climate, recorded prior to this period. In addition, from AD 1950, trees decreased while pioneer taxa increased, despite the stable influx of charcoal recorded during this period. This possibly indicates the effect of human activities that did not involve the use of fire, probably conducted by ethnicities other than the forager communities, which are still present in the area today. This thesis contributes significantly to the understanding of palaeoclimate, palaeoecology and the history of human subsistence in a biodiverse region of Madagascar, where no other record is currently available. Results from stable isotope analysis from baobabs showed a drying trend over the past 700 years, which has interacted with land-use to affect vegetation structure and composition over time. The pollen and charcoal results suggest the northern site, where vegetation was a mosaic of dry forest and riparian forest, experienced an impact of human activities through a shift to agriculture especially in the last 100 years. The savanna woodland of the southern site, however, was less affected by humans, probably as occupants were subsistence foragers, but the vegetation had a higher response to aridity. The results show that two distinctive human subsistence (pastoralism and foraging) were present simultaneously in the region until modern times. The northern site has evolved possibly from foraging into extensive agriculture, probably related to the fertility of the alluvial soil in the area, while the southern community remained dominated by foragers, while adopting today a seasonal practice of agriculture. From a conservation perspective, strategies of conservation for each ecosystem investigated here are proposed. In the northern site, monitoring and reducing fire-use within the dry forest ecosystem would allow tree recovery. In addition, restoring and establishing protected areas within the riparian forest would allow these ecosystems to act as refugia for regional biodiversity. Such measures will likely reduce the pressure on these ecosystems, where agriculture is a threat due to the availability of both water and fertile soil in their surroundings. Alternative livelihoods are required for the northern populace, for example through the exploitation of invasive aquatic plants such as Typha, which can be used in making of handcrafted artefacts, to reduce pressure on forest ecosystems through agricultural practices. For the southern site, maintaining the resilience of the savanna woodland through reforestation of functional species is also important to allow sustainability of services provided by these ecosystems. These strategies are applicable locally for Madagascar and for worldwide tropical dry forests, one of the globally most threatened vegetation types due to anthropogenic pressure and climate change.

Ecological restoration has the potential to provide a multitude of benefits, such as conserving biodiversity and supporting natural-resources dependent livelihoods. Tropical dry forests (TDFs) occur in densely populated human-modified landscapes in the tropics and are susceptible to degradation, making them an important biome to restore when degraded. TDFs are also socio-ecological systems, where local people rely on the forest for subsistence and livelihoods and effectively manage them for desire outcomes. People’s reliance on TDFs necessitates restoration projects to take into account more than biophysical and abiotic considerations when they are designed. In this decade of restoration, while there is the much-needed impetus to restore degraded land, to achieve enduring and just outcomes at large spatial scales, restoration projects need to more intentionally address local considerations, such as traditional land tenure systems and livelihood strategies, and goals such as socio-economic development. At the same time, to guide restoration efforts and realistically forecast the consequences of these efforts in the future, there is a need for rapid and accurate assessment tools to quantify the impact of restoration on biodiversity and people at several time steps. In Chapter 1, I use India, a country with high biophysical potential for restoration, as a case study to demonstrate a people-centric approach for identifying restoration opportunities. I find that there is a large overlap between areas of high biophysical restoration potential and high poverty, indicating potential and need to pursue restoration in a manner that addresses both ecological and social goals. In Chapter 2, I study a commonly adopted livelihood strategy, seasonal migration, in forest-dependent communities in India. I find that households in more agricultural and prosperous districts experience lower rates of migration but are more sensitive to climatic variability than households in poorer districts. In Chapter 3, I examine the impact of ecological restoration of a tropical dry forest in central India (CI). I find no significant difference in the cumulative number of bird species detected, but a significant difference in bird communities across the sites. In the lower frequencies dominated by birds and insects, I find that restored sites were positively associated with acoustic space occupancy in comparison to unrestored and low Lantana density (LLD) sites. In Chapter 4, I study the combined socio-ecological outcomes of restoration in the same sites in CI. I find that in the absence of alternative, people rely on Lantana camara, an invasive shrub, for subsistence and livelihoods, in the form of firewood and farm boundaries. I do not find any significant effect of restoration or LLD on people’s perception of ease of forest use, except for the distances covered for grazing, an important indicator of restoration success in this landscape. Finally, I also find that restoration is not associated with any significant changes in soundscapes in the higher frequency ranges dominated by insects and bats. Taken together, my chapters contribute to a greater understanding of the potential for restoration to meet social and ecological goals, the vulnerability of the livelihoods of people living on forest-fringes of TDFs to climate variability and expected and unexpected socio-ecological outcomes of restoration.