Orientadores: Ricardo Ribeiro Rodrigues, Flavio Antonio Maes dos Santos / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-21T20:07:39Z (GMT). No. of bitstreams: 1 Garcia_LeticiaCouto_D.pdf: 4213297 bytes, checksum: 251e5ae3edee734a1c9d00ebaa020ca4 (MD5) Previous issue date: 2012 / Resumo: A busca pela restauração de ambientes degradados tem sido um desafio em todas as regiões do planeta e há consenso de que estudos ecológicos podem contribuir para o aprimoramento da prática da restauração. No entanto, pouco se conhece sobre a trajetória dos ecossistemas em processo de restauração, especialmente quanto ao restabelecimento da diversidade de espécies e de suas funções nos processos ecológicos. O objetivo da pesquisa proposta foi verificar se há ou não a previsibilidade da recuperação de atributos ao longo do tempo, no que tange à diversidade de espécies, estrutura da vegetação, grupos funcionais, diversidade e redundância funcional e oferta de recursos para a fauna, em comunidades vegetais de matas ciliares em restauração em comparação com um ecossistema de referência. O objeto de estudo foram matas ciliares em região de Floresta Estacional Semidecidual, na região central do Estado de São Paulo, cujos plantios utilizaram elevada diversidade inicial. Foram amostrados mensalmente todos os indivíduos em reprodução de todas as formas de crescimento e a sua fenologia durante dois anos (353 espécies). Nestes indivíduos foram levantadas as características estruturais e reprodutivas, como: formas de crescimento, altura e área basal, fenologia, tipos florais, cores e tamanho das flores, índice de originalidade floral, síndromes de dispersão, cores e tamanhos dos frutos. Partiu-se da premissa de que o restabelecimento dos descritores estudados indica uma evolução positiva e autônoma dos ecossistemas em processo de restauração rumo à sua sustentabilidade. Alguns desses descritores se restabeleceram com o tempo, tais como a estrutura da vegetação, proporção de grupos sucessionais, diversidade de espécies arbóreas e sua funcionalidade e originalidade floral, quantidade de flores e frutos produzidos. Porém, ações de manejo adaptativo podem ser necessárias com vistas a suprir eventuais lacunas funcionais, principalmente no que tange às formas de vida não-arbóreas, devendo essas serem introduzidas, já que foram insuficientemente representadas, principalmente em áreas bastante fragmentadas. Desse modo, o manejo adaptativo dessas áreas poderá auxiliar na recuperação desses descritores. Para as futuras áreas que serão implantadas, a consideração desses fatores e o planejamento prévio de quais espécies, características funcionais e formas de vida a serem plantadas serão de grande relevância. Para completar o trabalho, acreditamos que aliar o conhecimento adquirido com políticas públicas e com a legislação ambiental nacional é indispensável. Desse modo, discutimos também o projeto de alteração da lei do Código Florestal brasileiro e os efeitos que poderão ocorrer na conservação e restauração dos ecossistemas nacionais / Abstract: Throughout the world there is large scale environment degradation. Hence, restoration of degraded areas has been a challenge. There is a consensus that ecological studies can contribute to improve the practice of restoration. However, there is a knowledge lack about the trajectory of ecosystems' under restoration; in particular, regarding re-establishment of species diversity and its function in the ecological process. The aim of the present study is to verify whether riparian forest communities under restoration recover their attributes over time, such as species diversity, structure, plant functional groups, functional diversity and redundancy and resource provision for fauna compared to a reference forest. We studied riparian forests of the seasonal semideciduous forest domain, in the Atlantic Forest Biome, São Paulo State, SE, Brazil. These areas were restored using a high diversity of species during the planting process. We sampled all reproductive individuals of all growth forms and followed their phenology monthly for two years (353 species). We measured reproductive and structural plant traits such as growth form, size, basal area, reproductive phenology, floral types, flower color and size, dispersal syndrome, fruit color and size. We assumed that recover of the studied descriptors indicates positive and autonomous advancement in ecosystem restoration towards its sustainability. Several of these attributes were re-established over time, such as the vegetation structure, ecological sucessional group proportion, species diversity of trees and their flower functionality and originality, as well as the amount production of flowers and fruits. On the other hand, adaptive management actions may be necessary in order to afford any functional gaps, especially in regard to forms of non-tree species that should be introduced since they have been underrepresented, particularly in landscapes very fragmented. Thereby, adaptive management of these areas may assist the recovery of these descriptors. Consideration of these factors and prior planning of which species and grow forms should be planted will be of great relevance for areas that will be implemented in the future. We also believe that combining the knowledge acquired with public policy and the national environmental legislation is essential. Hence, we discussed the proposal bill to the Brazilian Forest Code and the effects that may occur in conservation and restoration of national ecosystems, where several current protected areas may lose protection and it will be a setback for conservation and restoration of Brazilian forests / Doutorado / Biologia Vegetal / Doutor em Biologia Vegetal

TerraSAR-X images have been tested for agricultural fields of corn and wheat. The main purpose was to evaluate the impact of daily temperatures in crop development to optimize climate induced factors on the plant growth anomalies. The results are completed by utilizing Geographic Information Science, e.g. tools of ArcMap 10.3.1 and databases of ground truth and meteorological information. Synthetic Aperture Radar (SAR) images from German Aerospace Center (DLR) are acquired and the field survey datasets are sampled, each per month for three years (2010-2012) but only for the crop seasons (April-October). Correlation between SAR images and farmland anomalies is investigated in accordance with daily heat accumulations and a comparison of the three years’ SAR backscatter signatures is explained for corn and wheat. Finding the influence of daily temperatures on crops and hence on the TerraSAR-X backscatter is developed by Growing Degree Days (GDD) which appears to be the most suitable parameter for this purpose. Observation of GDD permits that the coolest year was 2010, either rest of the years were warmer and GDD accumulated in 2011 was higher as compared to that of 2012 in the first half of the year, however 2012 had rather more heat accumulation in the second half of the year. SAR backscatter from farmland depicts the crop development stages which depend upon the time when satellite captures data during the crop season. It varies with different development stages of crop plants. Backscatter of each development stage changes as the roughness and the moisture content (dielectric property) of the plants changes and local temperature directly impacts crop growth and hence the development stages.

Two riparian habitats in southeastern Arizona provide the setting for a study of 127 plants useful to human foragers. A view of plant part availability is based on annual phenological profiles, and on historic and prehistoric records of plant use. Food choice is limited in March and April, but high August through November. Riparian plants also offer numerous non-food resources. Trees and shrubs serve more needs in relation to number of available species than do perennial herbs (including grasses) and annuals. Southwestern ethnographic literature hints that certain native taxa (Panicum, Physalis, Populus, Salix, Typha and Vitis) might receive special care. Inherent qualities of parts, coupled with ethnographic records of preparation and use, provide a basis for speculation on which parts might survive in an ancient record. Most are expected to disintegrate in open sites. Parts sought for different needs can enter a dwelling via diverse routes that produce confusingly similar archaeological debris. Modern experiments to wash pollen from 14 separate harvests permit evaluation of plant fruit and leaves as pollen traps, to help interpret pollen recovered from ancient dwellings. High amounts of Berberis, Rumex and Ribes pollen, sometimes in clumps or as tetrads, travel on harvested fruit. Arctostaphylos, Monarda, Oxalis, Rhus, Rhamnus, Vitis and Juniperus parts carry lower amounts. Quercus and Gramineae pollen grains travel on parts of other taxa, as well as on their own fruit. The phenological profiles offer insight into group life-form activities in response to local temperature and precipitation trends. Rising and maximum temperatures coincide with intense vegetative and reproductive activity for trees, shrubs, herbaceous perennials, and annuals. Increased levels of precipitation coincide with maximum flowering and fruiting of herbaceous perennials and fall annuals. Limited data on six taxa from Utah generally agrees with observations in this study, suggesting strong genetic control in the phenology of some riparian taxa.

Linking environmental variation to population dynamics is necessary to understand and predict how the environment influences species abundances and distributions. I used demographic, environmental and trait data of forest herbs to study effects of spatial variation in environmental factors on populations as well as environmental change in terms of effects of forest succession on field layer plants. The results show that abundances of field layer species during forest succession are correlated with their functional traits; species with high specific leaf area increased more in abundance. I also found that soil nutrients affect vegetative and flowering phenology of the forest herb Actaea spicata. The effect of nutrients shows that a wider range of environmental factors than usually assumed can influence plant phenology. Moreover, local environmental factors affected also the demography of A. spicata through effects on vital rates. An abiotic factor, soil potassium affecting individual growth rate, was more important for population growth rate than seed predation, the most conspicuous biotic interaction in this system. Density independent changes in soil potassium during forest succession, and to a lesser extent plant population size dependent seed predation, were predicted to alter population growth rate, and thereby the abundance, of A. spicata over time. Because these environmental factors had effects on population projections, they can potentially influence the occupancy pattern of this species along successional gradients. I conclude that including deterministic, as opposed to stochastic, environmental change in demographic models enables assessments of the effects of processes such as succession, altered land-use, and climate change on population dynamics. Models explicitly incorporating environmental factors are useful for studying population dynamics in a realistic context, and to guide management of threatened species in changing environments.

Le biome boréal, emmagasinant d’importantes quantités de carbone en son sol et recouvrant une majorité du territoire alaskien, fennoscandien et russe, contribue grandement au système climatique. Toutefois, les variabilités climatiques et les propriétés de l’écosystème, notamment en ce qui a trait à la présence ou l’absence de pergélisol, complexifient la quantification de la variabilité des bilans de carbone du biome boréal, au sein duquel se retrouvent des écosystèmes forestiers, lentiques et de zones humides. Ces bilans de carbone sont grandement influencés par le début et la fin de la saison de croissance photosynthétique, étant à leur tour dépendants de plusieurs variables environnementales telles que la température de l’air et du sol, le contenu du sol en eau, les stades de développement de la végétation, etc. Cette recherche vise à quantifier l’impact de ces variabilités environnementales sur la variabilité des moments où se produisent le début et la fin de la saison de croissance photosynthétique, en distinguant les forêts boréales avec et sans pergélisol. La saison de croissance photosynthétique est caractérisée à partir de la productivité primaire brute dérivée de mesures covariance des turbulences provenant de 40 sites-années d’observation à travers la forêt boréale nord-américaine où l’épinette noire est l’espèce d’arbre dominante. Les variables environnementales considérées étaient les températures de l’air et du sol, les stades de développement de la végétation, le couvert nival, le rayonnement photosynthétiquement actif et le contenu du sol en eau. Le cadre statistique choisi incluait le calcul des coefficients de corrélations de Pearson, l’analyse des points communs et la modélisation par équations structurelles. Les résultats de cette étude montrent que la variabilité du début de la saison de croissance dans les sites sans pergélisol est contrôlée directement par la variabilité annuelle des stades de développement de la végétation ainsi que par le moment où survient le dégel du sol. Ce résultat souligne ainsi l’importance de l’accès à l’eau liquide du sol afin que la végétation initie la photosynthèse. Aucune variable environnementale ne pouvait significativement expliquer le contrôle du début de la photosynthèse au sein des sites avec pergélisol. À l’automne, le contenu du sol en eau ainsi que le début du couvert nival influencent directement la variabilité de la fin de la saison de croissance photosynthétique. Il est alors montré que la disponibilité de l’eau peut mener à une cessation plus hâtive de la photosynthèse à l’automne. L’effet de l’apparition du couvert nival est quant à lui opposé dans les sites avec et sans pergélisol. Son retard dans les sites sans pergélisol témoigne d’une température de l’air suffisamment élevée pour que les précipitations tombent sous forme liquide, prolongeant ainsi les activités photosynthétiques. Son retard dans les sites avec pergélisol signifie plutôt des précipitations neigeuses moindres, retardant ainsi l’apparition d’une couche isolante pour le sol, qui aurait pu allonger la saison de croissance photosynthétique. Cette étude contribue à clarifier les processus contrôlant le début et la fin de la saison de croissance photosynthétique et aidera à améliorer la compréhension des effets des changements climatiques sur la force du puits de carbone de la forêt boréale nord-américaine. / The boreal forest, storing large amounts of carbon in its soil and covering a majority of the Alaskan, Canadian, Fennoscandian and Russian territory, is an integral part of the climate system. However, climatic variability and ecosystem properties, particularly with regards to the presence or absence of permafrost, limits our understanding of the carbon balance variability in the boreal biome, which comprises forest, lake and wetland ecosystems. The boreal carbon sink-source strength is greatly influenced by phenological events, including the start and end of the photosynthetic growing season, which are themselves dependent on several environmental variables such as air and soil temperature, soil water content, vegetation development stages, etc. This research aims to provide new insights on the influence of environmental variability on the variability in the timing of the photosynthetic growing season, by broadly distinguishing between boreal forests with and without permafrost. The photosynthetic growing season is characterized using gross primary productivity derived from eddy covariance measurements of net ecosystem carbon dioxide exchange. Data from 40 black spruce- dominated site-years of observation across the North American boreal forest are used. The considered environmental predictors were air and soil temperatures, vegetation development stages, snow cover, photosynthetically active radiation and soil water content. The statistical framework included the calculation of Pearson correlation coefficients, commonality analyses and structural equation modeling. This study shows that the variability in the start of the growing season in permafrost-free sites is directly controlled by the variability in vegetation development stage as well as by the thawing of seasonally frozen ground. This result thus emphasizes the importance of access to liquid soil water for the vegetation to initiate photosynthesis. No environmental variable could significantly explain photosynthesis recovery in sites with permafrost. In fall, the soil water content as well as the start of snow cover directly influence the variability in the end of the photosynthetic growing season. These results suggest that the availability of water can limit photosynthesis in the fall. The effect of snow cover is opposite in sites with and without permafrost. A delay in the appearance of continuous snow cover in sites without permafrost indicates that the air temperature is high enough for precipitation to fall in liquid form and for photosynthesis to continue. In contrast, its delay in sites with permafrost indicates less snowfall, thus delaying the appearance of an insulating layer for the soil, which could have lengthened the photosynthetic growing season. This study sheds light on the controls of the annual variation of the timing of the photosynthetic growing season and will help understanding of the effects of climate change on the strength of the North American boreal forest carbon sink.