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Estimating the on-site and off-site impacts of soil erosion as a function of land use and climate conditions in semi-arid basins is key for soil and water conservation strategies. However, a research gap exists in the theme, requiring further investigation using local hydrological data. To accomplish it, the SDR-InVEST model was applied to the Pardo-FB basin (Brazil) using different land use, soil conservation, and climate conditions. The mean annual soil loss and the mean sediment yield in the basin varied between 7 and 36 Mg ha−1 yr−1 and 1.2 and 52.2 Gg yr−1, respectively. The basin areas where on-site and off-site erosion tolerances were exceeded ranged from 20% to 50% and from 0% to 1%, respectively, depending on the scenario. The results indicate that anthropic areas and high erosivities increase soil detachment and decrease sediment retention, generating higher erosion and sedimentation rates in the basin. The restoration of native vegetation and soil conservation practices reduced the erosion impacts, but their effectiveness was reduced in the wet climate scenario. The results contribute to the establishment of soil conservation strategies in the Pardo basin, as well as in similar basins around the world.

Climate change is a global phenomenon that affects biophysical systems and human well-being. The Paris Agreement of the United Nations Framework Convention on Climate Change entered into force in 2016 with the objective of strengthening the global response to climate change by keeping global temperature rise this century well below 2 °C above pre-industrial levels and to pursue efforts to limit the temperature increase even further to 1.5 °C. The agreement requires all Parties to submit their “nationally determined contributions” (NDCs) and to strengthen these efforts in the years ahead. Reducing carbon emissions from deforestation and forest degradation is an important strategy for mitigating climate change, particularly in developing countries with large forests. Extensive tropical forest loss and degradation have increased awareness at the international level of the need to undertake large-scale ecological restoration, highlighting the need to identify cases in which restoration strategies can contribute to mitigation and adaptation. Here we consider Brazil as a case study to evaluate the benefits and challenges of implementing large-scale restoration programs in developing countries. The Brazilian NDC included the target of restoring and reforesting 12 million hectares of forests for multiple uses by 2030. Restoration of native vegetation is one of the foundations of sustainable rural development in Brazil and should consider multiple purposes, from biodiversity and ecosystem services conservation to social and economic development. However, ecological restoration still presents substantial challenges for tropical and mega-diverse countries, including the need to develop plans that are technically and financially feasible, as well as public policies and monitoring instruments that can assess effectiveness. The planning, execution, and monitoring of restoration efforts strongly depend on the context and the diagnosis of the area with respect to reference ecosystems (e.g., forests, savannas, grasslands, wetlands). In addition, poor integration of climate change policies at the national and subnational levels and with other sectorial policies constrains the large-scale implementation of restoration programs. The case of Brazil shows that slowing deforestation is possible; however, this analysis highlights the need for increased national commitment and international support for actions that require large-scale transformations of the forest sector regarding ecosystem restoration efforts. Scaling up the ambitions and actions of the Paris Agreement implies the need for a global framework that recognizes landscape restoration as a cost-effective nature-based solution and that supports countries in addressing their remaining needs, challenges, and barriers.

Land occupation and management systems have defined fire regimes and landscapes for millennia. The savanna biome is responsible for 86% of all fire events, contributes to 10% of the total carbon emissions annually and is home to 10% of the human population. European colonization has been associated with the implementation of fire suppression policies in many tropical savanna regions, markedly disrupting traditional fire management practices and transforming ecosystems. In this paper we assess savanna burning approaches from pre-colonial to contemporary eras in three regions: northern Australia, southern Africa and Brazil. In these regions, fire suppression policies have led to (i) conflicts between government authorities and local communities; (ii) frequent late dry season wildfires and/or (iii) woody encroachment. Such consequences are facilitating changes to fire management policies, including recognition and incorporation of traditional ecological knowledge in contemporary community-based adaptive savanna fire management. Such programs include implementation of prescribed early dry season fires and, in some regions, generating income opportunities for rural and traditional communities through the reduction of late dry season wildfires and associated greenhouse gas emissions. We present a brief history of fire management policies in these three important savanna regions, and identify ongoing challenges for implementation of culturally and ecologically sustainable fire management policies.

Resumo A expansão de áreas de pastagens e cultivos agrícolas foi responsável pela maior parte do desmatamento no norte do estado de Minas Gerais. No presente estudo, avaliou-se a dinâmica do uso e cobertura da terra ocorrida nas últimas décadas (1986 a 2015) na Reserva de Desenvolvimento Sustentável Nascentes das Geraizeiras (RDS-NG) e em uma zona de 10 km do seu entorno no estado de Minas Gerais. Avaliaram-se também os efeitos do desmatamento sobre a fragmentação da vegetação natural usando dados de sensoriamento remoto e análise da paisagem. Os resultados deste estudo indicam que o desmatamento afetou mais da metade da vegetação natural até 2015, agravando a integridade dos fragmentos de vegetação nativa na área de estudo. A RDS-NG contribuiu para mitigar a fragmentação da vegetação natural ocorrida no entorno daquela Reserva com a regeneração natural de algumas áreas degradadas. Observou-se que a maior ameaça ambiental à reserva é a ocorrência do fogo, que varia anualmente em extensão e danos socioambientais. O uso sustentado das terras na RDS-NG pode ser melhorado com a ampliação das práticas de atividades econômicas sustentáveis, como o aproveitamento de produtos florestais não madeireiros, a implantação de consórcios agroflorestais e outras atividades econômicas de forma moderada. Essas práticas contribuirão para garantir a manutenção dos recursos naturais, a produção econômica e a geração de renda e trabalho à comunidade local, com inclusão de todos os segmentos sociais da população da Reserva e seu entorno. Abstract The expansion of pastures and cropping fields was responsible for most deforestation in Northern Minas Gerais state. In this study, we assessed the dynamics of land use and cover that occurred in recent decades (1986 to 2015) in the Sustainable Development Reserve Nascentes das Geraizeiras (SDR-NG) and a 10 km buffer zone in the state of Minas Gerais. The effects of deforestation on native vegetation fragmentation were also evaluated using remotely sensed data and landscape analysis. This study indicates that deforestation affected more than half of the native vegetation by 2015, which affected the integrity of native vegetation fragments in the entire study area. The SDR-NG contributed to mitigating the fragmentation of natural vegetation that occurred around that Reserve because of a secondary regrowth observed in some previously degraded areas. It was observed that the most significant environmental threat to that Reserve is fire events, which vary annually in extent and socio-environmental damages. The land sustained use in the SDR-NG could be improved by expanding sustainable economic activities, such as using non-timber forest products, the implementation of agroforestry systems, and other economic activities moderately. These practices will ensure the maintenance of natural resources, economic production, increase income and labor opportunities to local communities, and include all social segments and populations living within and around that Reserve.

Plant population response to ecological and anthropogenic factors provides essential information for conservation and management, mainly for species occurring in ecosystems under intense and rapid land use changes, like the Cerrado. We assessed the effects of land use and management upon the distribution of size and on the frequency of life stages of Butia capitata, an intensively harvested fruit palm, endemic to a southeastern portion of the Brazilian Cerrado. Most populations had a reverse-J size-class distribution, indicating good recruitment in the landscape even under fruit harvesting pressure and extensive cattle ranching. Regeneration was null or scarce in areas under more intense land use and management pressure, such as found on large, industrial farms. Soil fertility and texture were associated with seedling frequency, soil texture with sapling frequency, and precipitation with juvenile frequency. These factors must be taken into account for the enrichment, introduction and restoration of populations, actions demanded by traditional populations and family farmers who harvest the valuable fruits of B. capitata. Populations in areas with intense land use and inadequate management practices may be doomed to plummet. In contrast, in areas managed by traditional peoples and family farmers, characterized by low intensity of fruit harvesting and low frequency of cattle, populations should persist. Supporting traditional peoples and family farmers’ livelihoods and promoting changes in the management of areas where the species occurs may contribute to in situ conservation of the Cerrado’s biodiversity in multiple-use landscapes.

Crop wild relatives (CWR) are a key component of the world’s biota since they have the potential to contribute traits for crop improvement. The rich flora of the Brazilian Cerrado harbours a large number of CWR, but little is known about their distribution and conservation status. This study focused on the conservation of cassava (Manihot) wild relatives in the Cerrado. To accomplish this, we performed herbarium and field surveys to assess species conservation status based on geographic distribution, population density estimates, and rates of habitat loss. We found 75 species of Manihot occurring in the Cerrado, including 59 endemics. Among the endemic taxa, 24 are at some level of threat according to IUCN classification (14% Vulnerable, 22% Endangered, 5% Critically endangered), mostly owing to narrow geographic range and habitat loss. Most species are locally abundant, ranging from 55 to 1493 mature individuals per hectare. A quarter of the species recorded have been described over the past 5 years, indicating that the diversity of Manihot in the Cerrado is still underestimated. Areas of high species richness and endemism coincided mostly with Cerrado highlands, particularly in northern Goias state. Field surveys in 16 reserves indicate that 54% of Cerrado endemics are not represented in these protected areas. We believe that the patterns of distribution and conservation status uncovered here for Manihot are representative of many plant groups that are particularly diverse in high-altitude areas in the Cerrado. This calls for expansion of the network of protected areas to cover a wider range of environments, particularly those with a concentration of rare and endemic species, to ensure the effective in situ conservation of CWR present in the Cerrado flora.

Land use changes affect the abundance of plants, and even when plants are spared in agroecosystems, they are further impacted by management practices. Knowing how populations are impacted and the factors affecting them in the landscape is a major challenge in ecosystems under intense land use conversion, an even more important task when the plant is important for livelihoods. To understand how anthropogenic and environmental factors affect plant abundance and the population structure of Annona crassiflora, an important wild fruit tree of Cerrado, we evaluated populations in a gradient of anthropogenic and environmental conditions. Our sampling ranged from well-preserved sites, in natural areas, to highly disturbed pastures in the agroecosystems, covering an extensive area of the Cerrado biome. Results indicate that vegetation thinning and the presence of cattle negatively affect the abundance of small plants. High frequency of thinning and large cattle herds prevent recruitment of small plants in pastures, which may drive populations to local extinction in these sites. Reducing the frequency and intensity of vegetation thinning and cattle herd size may allow the recruitment of small plants into higher life stages. Fruit harvesting, which is positively associated with plant abundance, can continue to be practiced.

In the middle of a political and fiscal crisis, the Brazilian government is applying successive budget cuts, including in science funding. Recent cuts radically affect research programs on biodiversity that are crucial components for the design and monitoring of public policies for nature conservation and sustainable development. We analyze the consequences of such cuts on the Research Program on Biodiversity (PPBio), the largest biodiversity research network in Brazil (626 researchers, nine networks in all Brazilian biomes). Brazil holds a substantial part of the world's biodiversity and of tropical forests that play a significant role for regional and global climate stability. If underfunding is maintained, the dismantling of the Brazilian PPBio will have consequences that go beyond biodiversity knowledge itself but affect society as a whole. Brazil will likely fail to reach the National Targets for Biodiversity 2011–2020, and it will be difficult to fulfill the restoration target of the Brazilian NDC and to advance with the sustainable development goals. © 2017 Associação Brasileira de Ciência Ecológica e Conservação

Global sustainability rests on a myriad of benefits provided by natural ecosystems that support human livelihoods and well-being, from biodiversity persistence to climate regulation. The undeniable importance of conserving tropical forests has drawn most of the conservation spotlight towards it. However, open ecosystems such as the Brazilian Campo Rupestre (rupestrian grassland), have been historically overlooked despite their high diversity and key associated ecosystem services. We highlight major current threats to the persistence of the Campo Rupestre emphasizing its ecological, social, cultural, geo-environmental, and economic importance. We call attention to the importance of the Campo Rupestre as a reservoir of biodiversity and ecosystem services and offer priority actions that resulted from discussions involving scientists, industry representatives, environmental managers, and other members of civil society. Proposed actions include efforts related to ecological restoration, sustainable ecotourism, protection of traditional ecological knowledge, identification of emerging research questions, and development of tailored public policies. Such issues are integrated into a framework that collectively represents a road map to safeguard the Campo Rupestre from further degradation and steer its historical overexploitation towards sustainable management. Safeguarding the future of non-forest biomes like this poses a challenge to current paradigms of nature conservation. By establishing priorities and guidelines, we propose an actionable plan, which we hope can support informed decision-making policy towards a sustainable use of the Campo Rupestre. Long Term Ecological Research PELD-CRSC-17 Conselho Nacional de Pesquisas CNPq/MCTI Fundação de Amparo à Pesquisa do Estado de São Paulo 2013/50155-0, 2010/51307-0, 2019/07773-1

O presente trabalho aborda a questão dos ecossistemas e o reflorestamento para a restauração ecológica e a preservação da biodiversidade.

Large-scale commercial cattle ranching is the main driver of deforestation in the world, with several negative environmental and social impacts. To meet the growing demand for animal products, silvopastoral systems (SPS) can be an alternative as they have greater biodiversity and offer more environmental services than conventional cattle ranching systems. This paper aims to describe the implementation of SPS by traditional farmers in a rural settlement in southeastern Brazil, and the impacts on biodiversity of native plants. SPS were implemented by farmers in three selected areas that were cleared with a tractor. The impacts on the community and populations of native plants were estimated through vegetation sampling before and after the implementation of the SPS. Direct observations and semi-structured interviews were conducted to describe the implementation of the system and to understand the criteria employed to spare species, to manage native plants and the advantages of these systems according to farmers’ perceptions. Before the implementation, 1038 trees from 50 species and 29 botanical families were surveyed in the three areas. The tractor cleared on average 72 % of the trees, decreasing the number of trees ha−1 from 692 to 180 and reducing tree richness in 43 %. On average, 89 % of the removed trees had diameter ranging from 5 to 10 cm, indicating farmers’ preference in sparing the thickest trees. Farmers also spare useful species that have socio-economic importance, such as timber, fruit trees, fodder and medicine. According to the farmers, the advantages of the SPS are the high concentration of useful species, the environmental services provided and the increase in livestock production. The system described has great potential to ensure food security, generating socio-economic benefits for farmers and contributing to biodiversity conservation.

The palm Syagrus coronata plays an important ecological role in the caatinga ecosystems and is a source of income and livelihood for rural communities in semiarid northeastern Brazil. Despite its ecological and socioeconomic importance, little is known about the environmental factors determining its geographic distribution. The main goals of this study were to investigate the influence of climatic and environmental factors on the geographic distribution of S. coronata and to evaluate the conservation status within its potential distribution area. We modeled the fundamental niche of S. coronata using the MaxEnt algorithm and assessed the degree of vulnerability of environmental suitability areas quantifying the representativeness of protected areas and the different land use and land cover classes. Results predicted that the distribution of S. coronata is determined mainly by seasonality of precipitation and precipitation of the coldest quarter of the year. The areas of suitability, despite their large geographical extent, showed a high degree of environmental vulnerability, mainly due to the high conversion rate of native vegetation areas into agriculture and livestock and the low representation of protected areas. The results indicate a low effectiveness of the system of conservation units to protect the species, with anthropogenic disturbances threatening the quality of habitats and the persistence of S. coronata populations. Results can be used to support actions for the conservation and management of S. coronata, as well as decision making on the design of protected areas.

Sustainable Harvest of Mangaba (Hancornia speciosa) Fruits in Northern Minas Gerais, Brazil. The harvesting of non–timber forest products can contribute to conserving biodiversity and improving quality of life for rural communities. However, overexploitation can generate negative impacts on harvested populations, demanding the establishment of sustainable management practices. We estimated the maximum sustainable harvest of Hancornia speciosa Gomes (Apocynaceae) fruits in a savanna in northern Minas Gerais state, Brazil. The structure and population dynamics were analyzed in 70 permanent plots (20 x 50 m) in the years 2008–2011. A matrix population model based on life stages (seedlings, saplings, adults 1, adults 2) was used to calculate the population growth rate (λ), the stable stage distribution and the elasticity, and to simulate the effects of different fruit harvesting levels. The population growth rate (λ) value was 1.02 (CI95% 0.98 to 1.05), the maximum sustainable fruit harvest rate was 87%, and the elasticity analysis indicated that survival of the larger–size adults is the most important parameter to maintain the population. Apparently, the H. speciosa population is stable, which may indicate that the current harvesting level is not affecting population regeneration. However, other natural or anthropic disturbances, such as charcoal production and fire, can increase adult mortality, leading to population decline.

We evaluated the survival and growth of Amburana cearensis, Cedrela fissilis, and Sterculia striata seedlings in three seasonally tropical dry forest fragments that were subjected to different logging levels (intact, intermediately and heavily logged). In each fragment, we planted 40 seedlings of each species and monitored these over a period of 1 year. The highest seedling survival rate (64%) occurred in the heavily logged fragment, which, however, also had the highest mortality risk for all species during the dry season. Only S. striata seedlings had different survival rates among the fragments. Height and diameter growth were higher at sites with higher canopy openness in the wet season. The survival and growth rates of seedlings planted in logged fragments indicate that this technique can be applied to restore and enrich logged forests of the Paranã River Basin.

Plant populations can respond to temporal environmental heterogeneity caused by natural disturbances, such as herbivory. Palm individuals of several species are preyed upon by mammals, but the effects of such herbivory events on population dynamics remain poorly known. To evaluate the effects of environmental stochasticity on aGeonoma schottiana(Arecaceae) population, we surveyed annually 40 permanent 20 × 10-m plots in a riparian tropical forest over 5 y (2000–2004) and results were analysed using matrix models. The population growth rate (λ) was in equilibrium during the study period and only one bad year was identified (2002–2003), which had a higher mortality of juvenile individuals due to herbivory. Additionally, the bad year had a higher mortality of reproductive individuals than the other periods. The stasis matrix elements of the later life stages were the vital rates with highest elasticities. The mortality of juvenile and reproductive individuals had a negative contribution to λ in the bad year. Conversely, the growth of infant and juvenile individuals and the clonal growth of juveniles were the vital rates with highest contribution to stability maintenance of λ in the bad year in a life-table response experiment. The palm population had a high individual density, high proportion of the initial life stages, clonal growth, high fertility, abundant seed bank and high seedling recruitment. Despite these traits, if stochastic herbivory events occur frequently over a long period of time, the population will have a negative growth rate and the probability of local extinction will be very high.

In this study, we review the current available information on the social-ecological context of Brazilian tropical dry forests (TDFs), a vegetation type that covers approximately 3% of the country territory. For this purpose, we conducted a comparative analysis of two case studies, one study in the north of Minas Gerais state and the other in Parana River Basin, situated in southeastern and central Brazil, respectively. We compiled published bibliographical and census-based data for the two regions, concerning the historical human occupation and land use and the environmental and development policies affecting TDF management and sustainable use. Brazilian TDFs usually occur in semi-arid climates, and have been intensely converted mainly to extensive pasturelands in large farms, thus leading to high income concentration in those areas. Our case studies involve less-developed regions that support populations with very low human development indices, which is the norm for Brazilian TDFs. Many of these are traditional populations, such as indigenous and slave descendents, with peculiar cultural practices only recently considered in government policies proposed for the forest management. Though the two regions have similar land use histories, current social-ecological scenarios are very different. In the north of Minas Gerais, TDF conversion policies were debated intensely for the last 15 years, recently resulting in a state law specifically generated to regulate TDF use. Also, this region has 20 conservation units (CUs), some of them delimited inside the territories of the several traditional populations that inhabit TDF areas. This process caused enduring conflicts that can affect both CUs' effectiveness and the sustenance of these populations. In the Parana River Basin, there is no specific policy towards TDFs, whose use is regulated by the 43-year-old Brazilian Federal Forest Code. There are only four CUs in this region, and most traditional populations were expelled from their original territories and consequently lost their cultural identity. Government sustainability strategies are limited to the establishment of CUs, a response that may disregard social demands and cultural practices, depending on the local context. Given the uniqueness and threat level to TDFs, specific and more diversified policies towards land use should be established for these ecosystems in order to stimulate low-impact activities that maintain ecosystem services and improve the livelihoods of TDF inhabitants.

To understand the growth and reproduction of the palm Geonoma schottiana in the gallery forest of Central Brazil, two hypotheses were raised: (i) production of leaves and reproductive structures are concentrated in the period of the year with high light availability; (ii) leaf production and reproductive activity are related to plant length. However, it is expected that senility effects will cause fast reduction in growth and reproduction activities in higher plants. Growth and reproduction were concentrated in the dry season, when insolation is higher than in the wet season, suggesting that leaf and inflorescence production on G. schottiana in the gallery forest understory is more limited by light than by soil humidity. As the individual grows, leaf number and blade area increase, but reproduction activity is independent of plant length. Resources stored in the stem are important to growth, but exogenous factors, as canopy openness, should be more important to reproduction. Plant senescence seems to have a lesser effect on the production of vegetative and reproductive structures in G. schottiana than has been detected in congeneric species with greater clonal activity. Para compreender os fatores que influenciam o crescimento e a reprodução de Geonoma schottiana em mata de galeria no Brasil Central, foram levantadas duas hipóteses: (i) a produção de folhas e de estruturas reprodutivas está concentrada no período do ano de maior insolação; (ii) a produção de folhas e a atividade reprodutiva estão relacionadas ao comprimento do indivíduo. Entretanto, espera-se encontrar uma redução brusca nas atividades de crescimento e reprodução em indivíduos mais altos devido aos efeitos da senilidade. O crescimento e a reprodução ocorreram concentrados na estação seca, quando a insolação é maior do que na estação úmida. Assim, a produção de folhas e inflorescências de G. schottiana no sub-bosque de matas de galeria pode ser mais limitada pela luminosidade do que pela umidade do solo. Conforme o indivíduo cresce, o número de folhas e a área foliar aumentam, mas a atividade reprodutiva foi independente do comprimento do indivíduo. Os recursos armazenados no estipe são importantes para o crescimento, embora os fatores exógenos, como a abertura do dossel, possam ser mais importantes para a reprodução do que os carboidratos armazenados. A senilidade dos indivíduos parece ter um efeito menor na produção de estruturas vegetativas e reprodutivas ao contrário do que o tem sido detectado em espécies co-genéricas com maior atividade clonal.

We examined the following hypotheses: (i) seeds of dry forest trees have high pre- and post-germination mortality by desiccation due to the time between seed dispersal and germination and to irregular rains at the onset of the rainy season; (ii) seedlings from seeds dispersed in the dry season which survive the dry spells are larger at the end of the first rainy season than those dispersed in the rainy season because the former have more time to grow. We evaluated the possible trade-off between few large seedlings (resulting from natural dispersal) × many small seedlings (resulting from delayed dispersal) on seedling survival during the dry season. We sowed eight tree species in a greenhouse in September, simulating the natural dispersal timing (before the rains), and in November, when rains are more constant. Because shading can counteract the effects of desiccation, we applied three levels of shade (10%, 40% and 72% of PPFD). From September 2005 to December 2006, we provided the daily precipitation of a median year from a major patch of dry forest in Central Brazil. At the end of the rainy season, a subset of seedlings was collected for growth measurements (dry mass) and the remainder was left to follow the dry season survivorship. The lower germination expected for seeds dispersed in the dry season and in full sun was not confirmed for species that had some dormancy. The delayed dispersal was advantageous for the initial establishment of fast germinating species, but it was irrelevant or even disadvantageous for others. Also, the greenhouse weather was certainly milder than the natural environment, reducing the potential for mortality by desiccation. The growth of the four species of higher dormancy were not affected by timing of seed dispersal, while three out of four fast germinating species had higher root biomass when dispersed in the dry season. The growth during the rainy season did not affect seedling survival during the dry season. Keeping seeds to sow when rain is constant might be a good strategy to increase the establishment of fast-germinating tree species.

A venda de artesanato feito com escapos de S. nitens é uma importante fonte de renda na região do Jalapão, TO. Conhecer a época de produção e dispersão das sementes, bem como seu potencial germinativo, é essencial para propor formas de manejo que garantam a sustentabilidade econômica e ecológica deste extrativismo. Com o intuito de caracterizar a época de produção de sementes foram coletados capítulos entre agosto e dezembro/2003. Foram realizados experimentos de germinação em câmara a 22-30 ºC, sob foto e termoperíodo de 12 horas, e também em condições de escuro. Caracterizou-se também a germinação em condições de hipóxia (imersão em água) e acidez (pH 4 e 5). A produção de sementes iniciou-se em setembro e a maior parte da dispersão ocorreu entre outubro e novembro. A germinação das sementes coletadas entre setembro e outubro foi de 92 ± 7% (média ± DP), sementes coletadas a partir de novembro tiveram germinação significativamente menor. A acidez e a hipóxia não afetaram negativamente a germinação em relação ao controle. As sementes são fotoblásticas positivas e mantêm a germinação após congelamento a -20 ºC. A colheita de escapos após a frutificação (a partir do final de setembro) e a dispersão manual das sementes pelos próprios extrativistas no momento da colheita são estratégias importantes para o manejo da espécie e não prejudicam a atividade artesanal que está focada nos escapos e não nas flores, como ocorre para outras sempre-vivas.

We review the ecological and socio-economic impacts of the catastrophic dam failure in Mariana, Brazil. Tailing management practices by Samarco mining company ultimately caused a dam breach that abruptly discharged between 55 and 62millionm3 of tailings into the Doce River watershed. On November 5th, 2015, a tsunami of slurry engulfed the small district of Bento Rodrigues, loading the Doce River and its estuary with toxic tailings along a 663.2km trajectory, extending impacts to the Atlantic coast. Acute ecological impacts will adversely affect livelihoods of more than 1 million people in 41 riparian municipalities by reducing local access to fisheries resources, clean water, crop production sites, hydroelectric power generation and raw materials. The threats to riverine human communities are particularly critical for the disadvantaged populations from remote areas that rely on subsistence agriculture and fisheries, and are uniquely vulnerable to long-term heavy metal exposure. At the landscape scale, we predict multiple negative impacts, ranging from alterations of the genetic diversity of fish populations to long-term vegetation loss and poor regeneration in contaminated areas. Consequently, compromised soil stability and runoff control will increase the risk of further geomorphologic disturbance, including landslides, bank failure and mass movements. We propose spatially explicit long-term monitoring frameworks and priority mitigation measures to cope with acute and chronic risks. We posit that, from a national perspective, disastrous impacts like that of Doce River may become more frequent, given the recent regulatory changes that undermine both institutional governance structures and enforcement of environmental regulation.

We tested the relationship between the length of pasture use and the density, richness, and composition of naturally regenerating tropical seasonal deciduous forest in pastures. We sampled regenerating trees in 25 pastures distributed in four age classes ranging from < 6 to 40 yr of use. Density and composition of regenerating trees did not change with pasture age, but richness was lower in 25- and 40-yr-old pastures. Nonetheless, a number of species seem to be able to resprout even after 40 yr of ranching.

The goal of restoration is to accelerate ecosystem recovery, but in ecosystems that naturally regenerate rapidly restoration techniques need to be selected carefully to facilitate rather than impede natural recovery. We compared the effects of five restoration techniques, such as plowing the soil, removing grasses, adding forest litter, seeding, and planting nursery-growing seedlings, on the regeneration of seasonal deciduous forest trees in four abandoned pastures in central Brazil. We monitored all woody stems immediately prior to treatments and again 14 months after the treatments. We recorded an average of 16,663 tree stems per hectare and a total of 83 species before implementing treatments. Planting strongly increased species richness; adding litter and seeding had weaker positive effects on richness; and plowing and grass removal had no effect. Plowing substantially reduced the density of naturally established stems. Despite the high survival of planted seedlings, stem density in planting treatments did not change because the tractor and digging holes to plant seedlings caused mortality of naturally regenerating seedlings. Tree stems grew more in the grass release plots than in the control plots. Our results suggest that early succession of seasonal deciduous forest in pastures in the region studied does not need to be stimulated once the perturbation is stopped and that intensive restoration efforts may actually slow recovery. We recommend only enrichment planting of seedlings that are not able to resprout.

The handicrafts made from Syngonanthus nitens scapes have been an important source of income for rural communities in the Jalapao region of Brazil since the late 1990s. This study analyzed S. nitens harvest and management techniques and the economic importance of the handicrafts. We also tested the effects of harvest on S. nitens population ecology. Handicrafts provide about US$1,800/year per artisan, being especially important to women. Experimental scape harvesting in mid-October, which is when knowledgeable artisans harvest and when the seeds are mature, had no consistent effects on population density, plant survival, or reproduction (clonal or sexual) after one year. Since 40% of the new recruits come from seeds, harvest after seed maturation, combined with removal of only the scapes and not the flowerheads, can allow for S. nitens seeds to remain in the populations and help ensure sustainability of the growing S. nitens handicraft activity. Important economic aspects of S. nitens harvest sustainability include the high value of the handicrafts and the fact they are not perishable.

We studied the effect of forest gaps and cattle grazing on survival and growth of seedlings of seven native tree species, planted in dry forest fragments with different intensities of past logging in Central Brazil. Seedling survival after 12 mo ranged from 35 to 77 percent among species. Survival of most species was similar in gaps and understory in minimally disturbed forest remnants, but was lower in the gaps of more heavily logged forests. In contrast, growth was much higher in gaps than in understory in minimally disturbed forests, but for most species was similar in gaps and understory in more heavily logged forests. We did not detect an effect of cattle on seedling survival. Seedlings of the most commonly logged species show a high potential to survive and grow when planted in logged forests.

We assessed seed fate of six tree species in a seasonally deciduous forest of Central Brazil. Seed germination, predation, removal and death caused by pathogens or dessication were followed in an undisturbed forest site, a logged forest site, and an active pasture. In both forest types we sowed seeds under patches of liana tangles (Low Forest habitat) and under patches of mature forest (High Forest habitat). Seeds were monitored weekly for up to 8 months. Overall, small-seeded species ( Astronium fraxinifolium and Tabebuia impetiginosa ) had high germination, although germination was lower in the pasture due to insect predation. The hard-coated seeds of Erythrina sp. had higher germination rates in the pasture. The large-seeded Cavanillesia arborea and Swartzia multijuga had high seed removal (ca. 90%) in the pasture and under High Forest, but only 23–34% under Low Forest in the logged site. Lower removal of large seeds in Low Forest suggests that this habitat conceals the seeds and constrains the movement of large mammals. Both species were favored in Low Forest, suggesting that caution should be used when managing lianas. When protected from predation, seeds with a soft coat and high water content, such as the seeds of Eugenia dysenterica and S. multijuga , died from desiccation in the pasture. Restoration efforts must take into consideration high mortality caused by desiccation or insect predation in abandoned pastures of dry forests.

Seed dispersal, predation, desiccation and seedling survival are strong bottlenecks that impede tropical forest recovery on abandoned agricultural lands (reviewed in Holl 2002). The ability to resprout after disturbances overcomes these barriers, as those individuals bypass the seed stage and have more vigorous shoots than seedlings (Bond & Midgley 2001, Kammesheidt 1999, Kennard et al. 2002). Resprouting is a particularly important recovery mechanism in tropical dry forests (reviewed in Vieira & Scariot 2006). There are a number of reasons why resprouting may be more important in dry forests than in rain forests, including slower decay rates of trunk bases (Ewel 1980), or adaptation of plants to drought (Bond & Midgley 2001, Sampaio et al. 1993).

Physical damage caused by litterfall is a source of seedling mortality that can be influenced by environmental disturbances, such as the isolation of forest fragments due to habitat destruction. The impact of physical damage in seedling mortality was evaluated in forest fragments and continuous forests in central Amazonia using artificial seedlings. A total of 11 reserves distributed among three sites were studied: three 1-ha, three 10-ha, two 100-ha, and three continuous forest reserves. In each reserve, ten transects each comprised of ten artificial seedlings were monitored for one year at four-week intervals. Survival curves were compared using failure time analysis, and the effect of reserve size on artificial seedling mortality after one year was analyzed with a categorical model. In the analysis of survival curves, artificial seedling survival was significantly greater in the continuous forest than in the 10-ha reserve at one site only, a result that may have occurred by chance. After one y...

Tropical dry forests are the most threatened tropical terrestrial ecosystem. However, few studies have been conducted on the natural regeneration necessary to restore these forests. We reviewed the ecology of regeneration of tropical dry forests as a tool to restore disturbed lands. Dry forests are characterized by a relatively high number of tree species with small, dry, wind-dispersed seeds. Over small scales, wind-dispersed seeds are better able to colonize degraded areas than vertebrate-dispersed plants. Small seeds and those with low water content are less susceptible to desiccation, which is a major barrier for establishment in open areas. Seeds are available in the soil in the early rainy season to maximize the time to grow. However, highly variable precipitation and frequent dry spells are important sources of mortality in seeds and seedlings. Collecting seeds at the end of the dry season and planting them when soil has sufficient moisture may increase seedling establishment and reduce the time they are exposed to seed predators. Germination and early establishment in the field are favored in shaded sites, which have milder environment and moister soil than open sites during low rainfall periods. Growth of established seedlings, however, is favored in open areas. Therefore, clipping plants around established seedlings may be a good management option to improve growth and survival. Although dry forests have species either resistant to fire or that benefit from it, frequent fires simplify community species composition. Resprouting ability is a noticeable mechanism of regeneration in dry forests and must be considered for restoration. The approach to dry-forest restoration should be tailored to this ecosystem instead of merely following approaches developed for moister forests.

1 The effects of fragmentation on quantitative measures of floristic diversity in a palm community were examined in the Biological Dynamics of Forest Fragments study area in central Amazonia. Three 1-ha, three 10-ha, two 100-ha and three continuous forest reserves, distributed among three sites, were surveyed. In each reserve, 10 20 × 20 m plots were sampled, resulting in a total of 110 plots representing 4.4 sampled hectares. 2 The taxon composition of this palm community was dominated by stemmed, understorey palms. A total of 23 225 individuals from 36 taxa was recorded; five of the taxa were not sampled in continuous forest. 3 Taxa richness did not vary across reserve size or sites unless taxa not sampled in the continuous forest were removed from the analysis. Smaller forest fragments then harboured fewer taxa in the seedling stage than large forest fragments or continuous forest, despite the short time since isolation (10–15 years). There was a significant effect of location on the number of taxa per plot for all life stages, but only seedling and total were significantly affected by reserve size. 4 Reserve size did not affect the Shannon and Evenness indices. Reserves of similar sizes were floristically more similar than reserves of very different sizes. 5 Palms are important for the structure and composition of the forest. Their conservation may require the establishment of a number of large reserves.