CHAPTER 2. BACKGROUND 14
2.1.2 Secondaryforest succession
Secondary succession is the process of regeneration and species turnover of, predomi- nantly, woody vegetation on land that was formerly forested. It is a continuous process but is often initiated by disturbance of the canopy cover causing an influx of solar radiation (Chazdon, 2014). As succession progresses with increasing forest age it can be conceptualised as di↵erent successional stages (Table 2.1). Forbs, grasses and sedge species are the first to colonise pastoral and agricultural land after abandonment (Uhl et al., 1988). Following shortly behind, light demanding pioneers, e.g. Cecropia species, begin to establish and complete canopy closure can occur within 4 years (Lucas et al., 2002). An understory comprised of, shade tolerant, later successional, e.g. Chrysophyl- lum species, and climax species develops beneath the canopy formed by the pioneer species. The more intermediate and later successional species emerge through the pio- neer canopy after 15 – 20 years (Uhl, 1987). This succesional stage eventually gives way to the climax species that will make up the mature forest. This final stage is not static as previously assumed (Richards, 1955) but rather in a dynamic state of equilibrium (Chanthorn et al., 2015). Its complex and diverse structure is maintained by frequent disturbances causing irregular mortality and recruitment of trees at small spatial and temporal scales (Brokaw, 1982; Chambers et al., 2013). Patterns of dominant processes in vegetation establishment vary at each stage of succession (Table 2.2). These patterns of succession are often visible in secondary forests in the BrazilianAmazon (Figure 2.2).
The polarimetric attributes extracted from the ALOS-2 PALSAR-2 data showed different sensitivity with the biophysical variables. In general, the volumetric scattering from canopies was most correlated with the structural parameters (DBH, Ht, G, S, and AGB), whilst angular decomposition were most correlated with land-use history. These differences in the polarimetric attributes responses of PALU and FC can be attributed by the structural differences in the regrowth pathways. The high intensity of past-use reduces the complexity of the secondaryforest by reducing not only the AGB, but also the species richness and composition [18,36]. For instance, the increment of the AGB in areas previously burned 4–5 times can be 50% less than in the areas abandoned right after clear-cut . Uhl et al.  reported a strong reduction in biomassaccumulation at eight years of the SF in the Central Amazon. The AGB was 60–87 Mg ha − 1 after 1 year of grazing, 28 Mg ha − 1 with 6 years of grazing and only 0.16 Mg ha − 1 with 11 years of grazing. This slow increment related to past land-use was significant up to 18-years-old, but disappear at AdvSS . Such differences on structural parameters of the SFs could highlight the divergences among polarimetric attributes by land-use history and biophysical variables.
The extent to which our findings of a lack of effect of N 2 fixers on biomassaccumulation during secondaryforest succession are consistent across Neotropical forests that vary widely in environ- mental conditions (Quesada et al., 2010, 2012), biomass accumula- tion rates (Poorter et al., 2016), fixer abundance (Gei et al., in review; Liao, Menge, Lichstein, & Ángeles- Pérez, 2017; Pellegrini, Staver, Hedin, Charles- Dominique, & Tourgee, 2016; ter Steege et al., 2006) and fixer species community composition (S. A. Batterman, pers. comm.) remains unclear. In addition, we focus our study on the above- ground dynamics of trees and their contribution to eco- system N 2 fixation. The biomass of trees comprises the majority of biomass in tropical forests and trees (Saatchia et al., 2011), but nev- ertheless the role of below- ground biomass pools and interactions require further examination as resource competition is a net mea- sure of above- and below- ground plant–plant interactions. Roots account for a substantial proportion of tree biomass (almost 30 percent of the total biomass of young trees in a nearby plantation; Sinacore et al., 2017) and root:shoot ratios and root architecture are likely to shift along successional and other environmental gra- dients (Jaramillo, Ahedo- Hernández, & Kauffman, 2003; Rasmann, Bauerle, Poveda, & Vannette, 2011; van Noordwijk, Cadisch, & Ong, 2004; Zangaro, Alves, Lescano, Ansanelo, & Nogueira, 2012) and to differ across tree species and functional groups (Becker & Castillo, 1990; Markesteijn & Poorter, 2009; Shukla & Ramakrishnan, 1984; Sinacore et al., 2017). Including roots in future studies is a major challenge but will refine our ability to understand the role of N 2 fixer species in secondaryforest succession.
In the Amazon region, height-diameter at breast height (H:DBH) models are important because dense forest understory makes it diicult and time-consuming to view the top of the canopy to measure the tree heights. Several H:DBH models have been proposed for old-growth tropical forests for that purpose (Feldpausch et al. 2011; 2012; Hunter et al. 2013), however, they are scarce for secondary forests (Lucas et al. 2002; Neef and Santos 2005). For instance, Lucas et al. (2002) used genus-speciic nonlinear models to estimate tree height based on diameter for the most common species from a secondaryforest in Manaus (central Amazon). Conversely, Neef and Santos (2005) estimated tree height, and its increments, at stand-level age based on the Bertalanfy– Chapman–Richards model in a secondaryforest in Santarém (eastern Amazon). Other models related to H:DBH include the logistic, Weibull, and Richards models (Fang and Bailey 1998; Huang et al. 2000).
It is difficult to define AGB strata derived from environ- mental factors, such as vegetation, soil, precipitation and topography data. The interrelationships between these fac- tors are not completely understood at the regional scale [18, 31, 73]. A better comprehension is urgently required to stratify and improve AGB estimations . The implica- tions of not considering stratification, based on either veg- etation types, slope aspects, or the combination of both, for AGB estimations are the cost, time and work of estab- lishing forest inventory plots and the high cost of acquiring airborne LiDAR transects due to the large area of the Bra- zilian Amazon biome. Thus far, there has been no consen- sus on AGB stratification in the BrazilianAmazon biome, which is why the NFI and the EBA project have opted for a systematic sampling instead of a stratified one. Our esti- mation of the number of AGB plots for each environmen- tal factor map shows that the maps have many strata with a few large classes where most plots are located. The NFI, EBA and SL AGB data could be used to analyze which environmental factor map (or which strata) better repre- sents AGB. Moreover, variance analyses of the AGB data (of maps and available plots) within each environmental factor map class should be considered in future studies.
region show that TS and PV areas presented much higher particulate matter values than the control area, this validating the choice of CH as a control in this study and corroborates with the toxicity evaluation study of Sisenando et al.  who also chose this same area as a control. With respect to meteorological vari- ables, results presented show no significant difference between mean temperatures modeled among the areas. Higher humidity in Porto Velho in comparison to other points is justified by the fact that the area is part of the Amazon biome and consequently suffers greater influ- ence from humidity emanating from the Amazon rain- forest [39,40].
dressing the dual goals of improving agriculture and forest conservation, the identification of such policies has been problematic (Angelsen and Kaimowitz 2001). For example, Cattaneo (2001) finds that a reduction in transportation costs for agricultural goods leads to an increase in defor- estation, while White et al. (2001) find that households increase the intensification of pasture management only when this option is cheaper than cutting surrounding forest. Vosti, Carpentier, Witcover, and Valentim (2001) find that defores- tation continues to increase when intensive sys- tems of pasture are adopted, and Pichón et al. (2001) find that labor intensification strategies are linked to a reduction in land-clearing only in cases where the household is labor-constrained. This paper adds to this continuing research by investigating the intensification of cattle and dairy production. While cattle are often noted as one of the driving forces of tropical deforestation, it must be recognized that they are also a vital part of the small landholder’s income and insurance base. And, since cattle are only likely to increase in numbers in these regions, the study of intensi- fication and management issues is imperative to the design of constructive developmental policy.
and explains the failure of laws for the conservation of the Amazon rain forest, more rigid in terms of size of the legal reserve on rural properties compared with those applied in the savanna (Rocco 2005; Martins 2011). The remain- ing vegetation of the Amazon in Maranhão is basically composed of rain forest with lianas, alternating between dense and open vegetation, showing a gradual transition from the wetter forest type to semideciduous forest, along a north-south gradient (Muniz 2011). In addition, the region includes a mosaic of disturbed landscapes mainly represented by secondary forests, managed plantations and pastures (Araújo et al. 2011).
Additionally, the tree component (eucalyptus) in the ICLF system is also an important carbon sink, because of its high potential to accumulate large amounts of carbon in the woody biomass and to provide more recalcitrant resi- dues .  observed that ICLF promoted higher carbon stocks when com- pared to an integrated crop-livestock system, no-tillage and native vegetation, not only in the surface layer, but also in deep soil layers (1 m). The higher car- bon stocks observed for ICLF was attributed to the deposition of the crop resi- dues on the soil surface, but also the greater amounts of residues provided by pasture and trees in deeper soil layers.
This research was supported by the NASA Earth System Science Fellowship (NESSF) Grant no. NNX07AN84N (F.D.B.E.-S. and M.K.), the NASA Terrestrial Ecology Program contribution to the Large Scale Biosphere-Atmosphere Experiment in the Amazon (LBA), CalTech Postdoctoral Fellowship at JPL (F.D.B.E.-S.), NERC consortia projects, AMAZONICA (NE/F005806/1, TROBIT) for support of RAINFOR and M.G., R.J.W.B., O.L.P., T.R.F., G.L-G., J.L. and Y.M., and two grants from the European Research Council (T-FORCES, O.L.P.; GEOCARBON, M.G., O.L.P. and Y.M.L.). We thank the Brazilian Ministry of Science and Technology for its support of the LBA program and the National Institute for Research in Amazonia (INPA) for implementation of this program. Development of the RAINFOR network including measurement of biomass dynamics has been supported by 34 different grants, especially the Moore Foundation. We thank the authorities in Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru and Venezuela, and colleagues across the region for support. We are grateful to Dr Jeff Chambers who brought several of us together in an excellent meeting in 2006 at Tulane University where the idea for quantifying the disturbance spectrum was born. The Carnegie Airborne Observatory is made possible by Moore Foundation, the Grantham Foundation for the Protection of the Environment, the John D. and Catherine T. MacArthur Foundation, the Avatar Alliance Foundation, the W.M. Keck Foundation, the Margaret A. Cargill Foundation, Mary Anne Nyburg Baker and G. Leonard Baker Jr, and William R. Hearst III.
National School-based Student Health Survey (PeNSE), led by the Brazilian Institute of Geography and Statistics in 2015, in which 9th grade students participated, it was found that 14.8% of students had suffered acts of bullying. Regarding the aggressors, 19.8% stated that they had already bullied, mocked, bashed, scolded or intimidated some of their classmates (IBGE, 2016). Therefore, the discussion of such theme in the present paper is considered relevant, since there is a need for better understanding he characteristics of such phenomenon and its consequences, along with the identification of the people involved, as bullying is often seen as a harmless joke, whereas it actually results from implied violence. Thus, the present study aims to identify the characteristics of the cases of bullying by students from the BrazilianAmazon, more specifically from Nossa Senhora da Conceição School, located in the municipality of Bujaru, State of Pará, in the year of 2017.In addition, it aims to identify which type of bullying occurs most frequently among the researched types (verbal, psychological, physical, sexual and cyberbullying) and what are the main forms of student involvement in the episodes.
The point to be stressed, however, is that the geomercantile privatisation of land was linked to forms of turning direct producers into labour, as already discussed. Even the policy of immigration was also a policy of making labour. During Pombal's policy of immigration, from 1751 to 1777, natives were settled close to some of these settlements under the ideological justification of ‘civilising' them by their contact with Westerners. In fact, native settlements were aimed at offering labour to those immigrants wanting to ascend to entrepreneurial small production.349 Moreover, the Lei de Terras of 1850 authorised the immigration of labour by private enterprises. This enforced previous law that conceded layers of the empire’s lands to the organisation of free labour colonies.350 Private immigration usually aimed at the immigration of labour that was also encouraged by Brazilian legislation. However, Westerners usually wanted to become autonomous producers and the crash between those different interests led them to abandon private settlements as was the case of the colonia N.S. do 6 in 1858-59 that was abandoned by foreign immigrants, who were replaced by Brazilian immigrants.351 Furthermore, even considering difficulties and failures of some official Western settlements, they made an important contribution to the supply of labour. The fact that some immigrants abandoned their plots due to distance from consuming centres and ports, poor natural fertility of soil,
In particular, cattle ranching appeared to be a profitable land-use option, even in the long run and without subsidies (Faminow 1998). It also be- came increasingly clear that the anti-inflationary policies of fiscal restraint and subsidy reduction had reduced the rate of deforestation only during the recessionary period of 1987–1991. As investment rates and economic growth recovered in the 1990s, the rate of deforestation gradually in- creased again (Young 1995). Finally, non-destructive alternatives such as non-timber forest product extraction, bio-prospecting, eco-tourism, and sustainable timber management were found to have much less economic potential than had been previously claimed (Southgate 1998). The recent literature thus paints a very different picture of Amazonia, one in which deforested land has economically profitable and sustainable alternative uses. The recent debate also points to a sharper conflict of interest be- tween economic development and forest conservation (Kaimowitz 2001), and emphasizes the importance of gaining a better understanding of the trade-offs.
In the upper Amazon River (AM), Brazil, it was observed in the large family farm va- riability pumpkin landraces, which is widely used in food. Local cultivars are grown in small areas, for consumption in agricultural production and marketing unit in regional markets. The varieties of family agriculture are important sources of variability of germplasm characterization and require for their best knowledge. They still represent a featured action for the knowledge of genetic variability in conservation programs, use and breeding of the species.
When we analyze only %MCN of the dry season, we observe that stations DE, T-1 and T-2 showed the most important results, given that they were all statistically significant in both types of exposure. The response exhibited at station DE may be directly related to the proximity of the largest sugar cane plant of the region and to the fact that the municipality is the second lar- gest sugar cane producer in the area, which contains large plantations surrounding the city limits where non- mechanized harvesting is still practiced . The results of stations T (T-1 and T-2), both for micronuclei and pollutant levels, corroborate Ignotti et al.  and Rosa et al. , whose studies show that Tangará da Serra exhibits one of the worst indicators of morbidity and mortality from respiratory diseases in the southern region of BrazilianAmazon.
In Entangled Edens (2002), Slater speculates that the association of technology, wilderness and women warriors can be traced to early chroniclers who claimed to have seen Amazonian women wearing golden crowns, overseeing subterranean mines, and weeping tears of pure silver (83). The topos of the virgin territory changes over time, transforming the Amazon from a place to conquer into a place to respect and preserve. During the early part of the twentieth century, the Amazon was generally an unknown hinterland for most Brazilians, a remote place to be civilized for the nation, according to Brazilian journalist, author and engineer Euclides da Cunha (1866-1909), 2 or to be explored by the likes of military engineer Marechal Cândido Rondon (1865-1958), who supervised the laying of hundreds of kilometers of telegraphic wire in the Amazon and other remote regions of Brazil. 3 Yet for others, such as English explorer Percy Harrison Fawcett (1867-1925), 4 the region was key to solving the mysteries of the sunken city of Atlantis and its esoteric knowledge (Slater 240n3). During the military dictatorship, the vast region was the object of the military’s plans for economic development and gold mining, especially after the discovery of gold at the Serra Pelada mine in 1979 (Slater 105). In the post-dictatorship years, the Amazon became associated with the causes of ecology and the biodiversity, and what was previously conceived of as a “jungle,” became known as the “rainforest,” an area whose preservation was also justified by the presence and rights of indigenous peoples (Slater 149). 5 Thus, while early novels evoke the exoticism of the wilderness in lost world narratives, the more contemporary works examine the region’s political and ecological impact. Yet in both cases, the Amazon remains a special locus for the national imagination, where aspirations for national greatness and dramas of psychological trauma may be played out with this vast, isolated region as backdrop.
Surveys: The survey was two pages front and back. Not all the potential questions were included on the questionnaire. Since the researcher had to limit the length of the survey to a reasonable time frame, some meaningful questions had to be discarded. In addition, tourists who stayed in other type of accommodations instead of backpacker hostels were not surveyed, minimizing the chance to capture other types of tourists. The survey phase of the study relied on the researcher collecting data from backpacker hostels in Manaus and Bel é m cities, as the researcher is well trained in survey techniques, has had previous experience with surveys and is a Portuguese, Spanish and English language speaker. The researcher approached each respondent, making sure that the respondent completed the whole questionnaire. The low number of completed questionnaires (n=207) was due to the small size of the backpacker market in the BrazilianAmazon region, justifying the reason behind this study. Additionally, the researcher did not have the need to obtain a high number of respondents, because the qualitative data was dominant and the quantitative data was supplementary in this study (Section 3.5).
With MIC between 25 and 200 øg/mL, the extracts of Zanthoxilumsp(Rutaceae) also were active against RMPr strain and may have the antimicrobial activity justified due to the presence of alkaloids and flavonoids. These substance have already had their bioactivity previously proved as trypanocidal[18,19]. Others species of Rutaceae, also showed antimicrobial activity, that confirm the tendency of this family to synthesize secondary metabolites that are biologically active. The extracts of Zingiberzerumbet(Zingiberaceae) were active against M. tuberculosis H 37 R v and INHr strains with MIC of 200
Monitoring tropical forest cover is central to biodiversity preservation, terrestrial carbon stocks, essential ecosystem and climate functions, and ultimately, sustainable economic development. The Amazonforest is the Earth’s largest rainforest, and despite intensive studies on current deforestation rates, relatively little is known as to how these compare to historic (pre 1985) deforestation rates. We quantified land cover change between 1975 and 2014 in the so-called Arc of Deforestation of the BrazilianAmazon, covering the southern stretch of the Amazonforest and part of the Cerrado biome. We applied a consistent method that made use of data from Landsat sensors: Multispectral Scanner (MSS), Thematic Mapper (TM), Enhanced Thematic Mapper Plus (ETM+) and Operational Land Imager (OLI). We acquired suitable images from the US Geological Survey (USGS) for five epochs: 1975, 1990, 2000, 2010, and 2014. We then performed land cover analysis for each epoch using a systematic sample of 156 sites, each one covering 10 km × 10 km, located at the confluence point of integer degree latitudes and longitudes. An object-based classification of the images was performed with five land cover classes: tree cover, tree cover mosaic, other wooded land, other land cover, and water. The automatic classification results were corrected by visual interpretation, and, when available, by comparison with higher resolution imagery. Our results show a decrease of forest cover of 24.2% in the last 40 years in the Brazilian Arc of Deforestation, with an average yearly net forest cover change rate of -0.71% for the 39 years considered.