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O PNLD Literário estabeleceu-se como a maior política pública de fomento à leitura no âmbito nacional, substituindo seu antecessor, o PNBE. Entre 2020 e 2021, o projeto de pesquisa “PNLD Literário 2020 – Tendências da literatura juvenil” acompanhou o desenvolvimento e a efetivação do programa, proporcionando análises das obras que chegavam às escolas. Assim, o presente trabalho apresenta análises de obras selecionadas pelos professores do sistema educacional do município de João Pessoa através do PNLD Literário na sua edição de 2020. As obras analisadas fazem parte da literatura juvenil, um campo ainda em desenvolvimento no país, o qual também ainda carece de fortuna crítica no seu campo de estudos. A partir dos critérios de Antunes (2019) e Ceccantini (2020) as análises objetivaram parâmetros notáveis do gênero, a fim de avaliar a qualidade estética dos textos escolhidos, sendo eles: Quando meu pai perdeu o emprego (2018); Irmão Negro (2018); Malala, a menina que queria ir para a escola (2018); e A face oculta: uma história de bullying e cyberbulling (2018). No conjunto, as obras mostraram semelhanças na utilização de artifícios narrativos simplificados e, em alguns casos, uma despreocupação em proporcionar uma experiência estética aos estudantes os quais os livros são destinados.

We provide the first record of Xiphophorus maculatus (Günther, 1866) in a river basin in the northeastern Brazil. Specimens were collected in the Jaguaribe River basin, João Pessoa, Paraíba state, Brazil. Two hundred eighty-one specimens, corresponding to 143 males and 138 females of X. maculatus, were collected at nine sites along the basin, from 2017 to 2019. Specimens total length ranged from 17.5 to 26.6 mm in males and from 11.7 to 32.7 mm in females. Introduction of non-native species greatly threatens the biological diversity worldwide. When introduced into a new habitat, X. maculatus usually decreases microcrustacean, macroinvertebrate and native fish populations.

Evaluating the conservation of aquatic ecosystems, especially those which serve to supply, has been carried out using a variety of tools. However, the perception of water quality by the local community which lives in direct contact with water resources has not been considered with enough importance. This study analysed the relationship between the conservation status of reservoirs as perceived by the local community and their conservation status according to physical, chemical, and biological indicators. To do so, we calculated the Trophic State Index (TSI) of the reservoirs, the diversity and richness of benthic macroinvertebrate and we analysed the human influence in the riparian zone. Thus, we created the Community Conservation Perception Index (CCPI) to quantitatively associate the perception of the local community with environmental quality indicators (TSI, diversity, richness and anthropogenic influences in the riparian zone). We found that interviewee perception of reservoir conservation (using the CCPI) was related to trophic state, richness and diversity of benthic macroinvertebrate, and the presence of residences and agriculture in the riparian zone. It is necessary to consider the environmental perception of the local community as a relevant factor in management programmes and the conservation of ecosystems, even if artificial, as is the case with reservoirs. These communities can significantly contribute to maintaining the environmental quality through their performance in participatory management in projects such as: participating in the investigation of pollution in reservoirs, collecting parameters related to water quality, and community action in designing conservation strategies.

Evaluating the conservation of aquatic ecosystems, especially those which serve to supply, has been carried out using a variety of tools. However, the perception of water quality by the local community which lives in direct contact with water resources has not been considered with enough importance. This study analysed the relationship between the conservation status of reservoirs as perceived by the local community and their conservation status according to physical, chemical, and biological indicators. To do so, we calculated the Trophic State Index (TSI) of the reservoirs, the diversity and richness of benthic macroinvertebrate and we analysed the human influence in the riparian zone. Thus, we created the Community Conservation Perception Index (CCPI) to quantitatively associate the perception of the local community with environmental quality indicators (TSI, diversity, richness and anthropogenic influences in the riparian zone). We found that interviewee perception of reservoir conservation (using the CCPI) was related to trophic state, richness and diversity of benthic macroinvertebrate, and the presence of residences and agriculture in the riparian zone. It is necessary to consider the environmental perception of the local community as a relevant factor in management programmes and the conservation of ecosystems, even if artificial, as is the case with reservoirs. These communities can significantly contribute to maintaining the environmental quality through their performance in participatory management in projects such as: participating in the investigation of pollution in reservoirs, collecting parameters related to water quality, and community action in designing conservation strategies.

Abstract: Aim The study analyzed the potential use of the phytoplankton functional groups as an environmental bioindicator in aquatic ecosystems of Brazilian semiarid region. Methods Using data collected over five years of a natural lagoon and two reservoirs, we evaluate the relationship between functional groups and environmental conditions through the multivariate approach. The Q index was applied to assess ecological status in these ecosystems. Results In Panati, the temporary and natural lagoon, the partial habitat desiccation and presence of macrophytes reflected in the less nutrients concentrations and phytoplankton composition, with high biomass of coccoids Chlorophyceae, diatoms and desmids (functional groups J, MP and N, respectively). Taperoá and Soledade reservoirs presented high cyanobacteria contribution, however the biomass and contribution of cyanobacteria in Taperoá (SN, S1) were lower than in Soledade. In this reservoir, cyanobacteria were more abundant, alternating in dominance (LO, M, LM, SN, S1). According to tendencies revealed by Redundancy Analysis (RDA), the main driving abiotic factors on the phytoplankton functional groups were pH, nutrients and light availability. As expected, phytoplankton composition directly influenced the Q index result, showing mostly bad to tolerable conditions in Soledade, medium to good in Taperoá and good to excellent in Panati. Conclusions The Q index was a good tool to assess the water quality and ecological status in aquatic ecosystems from the Brazilian semiarid region, reflecting the influence of natural control mechanisms on the harmful cyanobacteria blooms in temporary ecosystems.

Abstract: Aim To determine the internal P loading potential of semiarid tropical reservoir sediment while verifying the driving factors that affect P release rates. Methods An experiment was performed with water and sediment from the reservoir Boqueirão de Parelhas in Brazil. The effects of three variables on P release were studied: air temperature (region average of 28 °C and 32 °C, simulating an increase of 4 °C), pH (region average of pH 8, more acidic pH 6 and more alkaline pH 10) and oxygen (presence and absence). In addition, P fractionation analysis was performed on the P forms in the sediment. Results It was found that the minimum P release was in an oxic treatment at pH 6 and temperature 28 °C (0.22 mg m-2 d-1 ± 0.13) and the maximum P release in an anoxic treatment at pH 10 and temperature 32 °C (2.1 mg m-2 d-1 ± 0.15). The total P in the sediment was 597 mg kg-1, and the major P form in the sediment was NaOH-rP, the P bound to aluminum, corresponding to 42% of the total P. Conclusion These results allow us to confirm that the sediment of the Boqueirão reservoir is susceptible to the release of P bound to aluminum due to the prevalence of this form in its sediments concomitant with the high temperatures and alkaline pH of the water. This scenario can be aggravated by climate change.

Phosphorus (P) is the main nutrient responsible for the harmful effects caused by the enrichment of aquatic systems, and submerged macrophytes play an important role in this process, since they can both remove and release this nutrient in environmental compartments. The present study aimed to evaluate the influence of submerged macrophytes on P in the water, sediment, and water-sediment interface in a eutrophic reservoir in a semiarid region and to evaluate the relationship between the concentration of this nutrient in macrophyte tissue and that available in the different compartments. Were performed ten collection campaigns, in three reservoir locations: at the entrance of the Paraíba River; in the intermediate area between the river entrance and the dam and at the dam. We observed a difference in the P concentration inside and outside macrophyte banks, and this difference was determined by the abundance and intensity of macrophyte growth and decomposition. In sites with extensive vegetation banks and where decomposition was more intense, macrophytes released P to the water-sediment interface and sediment compartments. By contrast, in sites with smaller vegetation banks and where macrophytes did not show reduced abundance, P was removed from these compartments. The entry of new water originating from river water transfer was an important modifying factor of the physical and chemical characteristics and macrophyte abundance. The zone where the river enters the reservoir was the area most affected by the water transfer. The macrophyte decomposition in this zone resulted in the highest P concentration in the water-sediment interface and sediment compartments, which demonstrates the importance of macrophytes in the fertilization of water bodies and, consequently, in the eutrophication process. In turn, in the dam zone, where the macrophyte banks were more stable and without large variations in abundance, P was removed from the compartments. A relationship between P in macrophyte tissue and that available in the environment was observed, particularly at the water-sediment interface, indicating that this compartment was the main P source for these plants, which demonstrated that these plants store higher amounts of P in nutrient-rich sediment and water, functioning as an indicator of the nutritional status of a reservoir.

Cyanobacteria harmful algal blooms (CyanoHABs) have become increasingly frequent and intense in public supply reservoirs as a result of eutrophication and global climate change. The semi-arid region of Brazil has a well documented history of CyanoHABs but the underlying factors that control the excessive proliferation of these organisms and the production of their bioactive secondary metabolites are not comprehensively understood. This study aimed to identify the environmental factors that explain the spatial and temporal variations in the abundance of cyanobacteria and the concentration of cyanotoxins (microcystins, saxitoxins, and cylindrospermopsin) in semi-arid reservoirs. The following hypotheses were tested: (a) the largest biovolumes of potential toxin producing cyanobacteria occur when cyanotoxin concentrations are highest; and (b) the environmental factors that explain variations in biovolume of cyanobacteria also explain changes in cyanotoxins concentrations. Samples were taken from four reservoirs located in the Northeast region of Brazil, over a three-month period (October 2016 and February and June 2017). Of the 24 species of cyanobacteria identified, 13 were potentially toxin-producing. Physicochemical variables such as water volume of the reservoir, water transparency, soluble reactive phosphorus, and total phosphorus explained the abundance of cyanobacteria and the levels of cyanotoxins. These results corroborate the hypothesis that similar physicochemical conditions influence the abundance and diversity of cyanobacteria and cyanotoxins. Cyanobacterial blooms composed of more than one potential toxin producing species were observed in the studied reservoirs, where potential microcystin-producing species were the most common. Microcystins and saxitoxins were detected in all the reservoirs studied, while cylindrospermopsin and the cyanobacterium Cylindrospermopsis raciborskii were simultaneously recorded in only one reservoir (Camalaú Reservoir). Cylindrospermopsin was only detected in a reservoir for the first time in the State of Paraíba. Canonical redundancy analysis showed that the cyanotoxins were related to potential toxin producing species. These results corroborate the proposed hypothesis that there is a correlation between cyanotoxins and the biomass of potential producers. Also, there were situations where cyanotoxins were detected without the presence of potential producers. These results demonstrate the need for reassessment of potential toxin producing species of cyanobacteria in semi-arid reservoirs. This may lead to the identification and characterization of novel producers of these bioactive secondary metabolites.

O presente estudo objetivou analisar a dinâmica de grupos funcionais do fitoplâncton e a variação do grau de trofia em reservatório do semiárido brasileiro durante estiagem prolongada. O estudo foi realizado no reservatório de Cordeiro, no município do Congo, Paraíba, com amostragens no período de junho a dezembro de 2015, com frequência trimestral, no ponto próximo ao barramento do reservatório. As espécies do fitoplâncton foram identificadas e quantificadas para obtenção da densidade, posteriormente as espécies foram classificadas de acordo com suas estratégias e grupos funcionais. O estado trófico foi determinado à partir do Índice do estado trófico para ambientes tropicais. O período de estudo foi caracterizado pela redução dos níveis de água acumulados no reservatório. A transparência do Secchi foi baixa, cujos valores foram inferiores a 1m. As concentrações de fósforo total durante o período de estudo foram elevadas (acima de 200 μg/L). As concentrações de clorofila a, tiveram valores mínimos de 8,17μg/L em julho de 2015, e máximos de 93,67 μg/L em outubro de 2015, com oscilações durante todo o período de estudo. O ambiente foi classificado como mesotrófico no mês de junho e eutrófico nos meses de outubro e dezembro. Foram identificadas dez espécies descritoras, agrupadas em quatro estratégias de vida (CS, C, R, e S) e 08 grupos funcionais (D, F, H1, N, P, X1 e Z). Os grupos funcionais refletiram as mudanças ambientais, sendo notória a presença de grupos típicos de lagos rasos meso-eutróficos. As espécies potencialmente tóxicas encontradas no estudo podem representar riscos à saúde das pessoas que utilizam essa água para consumo.

ObjectiveThe objective of this study is to evaluate whether the distribution of structural attributes of rotifers in reservoirs in the semiarid region is more strongly influenced by abiotic or biotic environmental factors (density of cyanobacteria).MethodSampling occurred in two reservoirs in the Paraíba Basin, northeastern Brazil (Poções and Camalaú) during April and June 2012. Eight sampling points were distributed at two stations in each reservoir: the region near the entrance of the main tributary and region of the dam and collections were made in the limnetic and littoral zone in every season. To assess the abiotic influence and density of cyanobacteria in the distribution of the structural attributes of rotifers, environmental variables bivariate correlation was conducted in series.ResultsIn Poções reservoir, the distribution of rotifer biomass was negatively related to the density of cyanobacteria; among the environmental variables, chlorophyll-a and total nitrogen were negatively related to all of the tested structural attributes, while the concentrations of total phosphorus were strongly related to the abundance of rotifers. In the Camalaú reservoir, the biomass was a structural attribute with a stronger correlation to the density of cyanobacteria; between the environmental variables and Egeria densa, nitrate was negatively related to all of the attributes tested, while transparency was moderately related to the abundance, biomass and richness as well as Chara sp. with abundance.ConclusionsAssemblages of rotifers are more clearly related to environmental conditions, especially those indicative of trophic conditions, despite the density of cyanobacteria having been a factor that was positively related to the structural characteristics of rotifers and thus indicative of such structural assemblies. This can be used for analysis of local environmental condition factors.

ObjectiveThis study analyzed the influence of ecological filters (abiotic variables) on the phytoplankton community in hypersaline ecosystems.MethodsThe abiotic variables measured herein were: pH, water temperature, salinity, ammonium ion, total nitrogen, nitrite, nitrate, total phosphorus, and soluble reactive phosphorus. The phytoplankton community was studied for density, richness and Shannon-Wiener diversity index. Data were analyzed using analysis of variance, linear regression and Canonical correspondence analysis (CCA).ResultsIn total, 110 taxa were identified in 3 solar salterns, distributed into 9 taxonomic classes, with the predominance of Cyanobacteria (41.8%) and Bacillariophyceae (22.7%). The species Pseudanabaena galeata was the only species sampled in all saline environments. Salinity significantly influenced the richness in the three salterns, Augusto Severo (F(1,22) = 23.2, p

AimIn this research, we aimed to model limnological parameters in the Salina Unidos (Macau-Brazil) using GIS technology. We hypothesized that in solar saltworks, the geochemical characteristics of the brines (i.e. the strong solution of salts) vary considerably through the salt ponds circuit, in which drastic changes can damage the entire salt production.MethodsGeochemical parameters were monitored in seven sampling points distributed along the salt ponds circuit, during a complete cycle of salt production, i.e., from January to December 2007. The open source software Spring 5.1.6 was used to build, store, analyze and model the spatial distribution of the parameters.ResultsWe identified a spatial gradient of the salinity and temperature, with values increasing from evaporation ponds to concentration ponds, showing a relationship with the salt production. The parameters, depth, dissolved oxygen concentrations and total dissolved reactive phosphorus showed a decrease from the evaporation ponds towards the concentration ponds. Among the dissolved inorganic nitrogen forms analyzed (NH3-, NO2- and NO3-), nitrate was the predominant, namely in the concentration ponds, where it reached the highest concentrations. The concentration of chlorophyll awas higher in the initial and intermediate evaporation ponds, showing a distinct dynamics of in relation to other environmental variables.ConclusionsThe increased concentration of the analyzed limnological parameters, from the evaporation ponds towards the concentration ponds, evidenced a heterogeneous distribution varying significantly with season. The geochemical spatialization of brine, as illustrated by GIS approach, is very important for the conservation of these environments because this spatial heterogeneity can provide a high diversity of habitat types. This spatial analysis proved to be a practical tool for an adequate management of solar saltworks considering the environmental (ecosystem) and the socio-economic aspects.

Aquatic systems in semi-arid Brazil include natural shallow lakes, artificial reservoirs and intermittent streams and rivers. These systems are distinctive features in the semi-arid landscape and comprise a range of associated systems functioning as an ever-changing mosaic of dry/wet patches. Lakes and reservoirs in semi-arid Brazil are subject to important periods of water shortages, whereas rivers and streams are characterized as highly variable and driven by the extremes of water flow and its absence. Within this view a catchment-scale approach must be used to create a holistic model to conceptualize and comprehend these aquatic systems, since the aquatic environment types in the semi-arid region of Brazil incorporate broader aspects within the catchment scale such as geomorphology, vegetation, climate and land use. This paper summarizes some of the information on the aquatic systems of the Brazilian semi-arid region and shows the importance of limnological studies in this region. It also attempts to establish perspectives for future research considering the catchment as a scale for surveying biological processes and limnological characteristics of the various aquatic systems. It is presented information on their overall structure and functioning, as well as characteristics of some biological communities, such as phytoplankton, periphyton, aquatic macrophytes, benthic invertebrates and fish. The importance of the understanding of eutrophication in reservoirs and the role of the dry phase in streams is emphasized, and information on possible actions of planning and management to improve water quality of reservoirs are presented.Os ecossistemas no semiárido brasileiro englobam lagos rasos naturais, reservatórios artificiais e rios e riachos intermitentes. Estes sistemas são particularidades na paisagem do semiárida e compreendem uma grande variedade de sistemas associados, funcionando como um mosaico em constante mudança entre épocas de seca e chuva. Lagos e reservatórios no semiárido brasileiro estão sujeitos a importantes períodos de escassez de água, enquanto que os rios e riachos são caracterizados como altamente variáveis e impulsionados pelos extremos de fluxo de água e sua ausência. Dentro desta perspectiva uma abordagem em escala de bacia hidrográfica deve ser usada para se criar um modelo holístico para conceituar esses sistemas aquáticos, uma vez que os tipos de ambientes aquáticos na região semiárida do Brasil incorporam aspectos mais amplos dentro da escala de bacia hidrográfica como geomorfologia, clima, vegetação e uso da terra. Este artigo sintetiza algumas das informações sobre os sistemas aquáticos da região semiárida brasileira e mostra a importância de estudos limnológicos nesta região. Ele também tenta estabelecer perspectivas para pesquisas futuras considerando a bacia hidrográfica como uma escala para levantamento de processos biológicos e as características limnológicas dos vários sistemas aquáticos. É apresentada informações sobre sua estrutura e funcionamento geral, bem como características de algumas comunidades biológicas, tais como o fitoplâncton, perifíton, macrofitas aquáticas, invertebrados bentônicos e peixes. A importância do entendimento da eutrofização em reservatórios e o papel da fase de seca em riachos são enfatizados, e informações sobre possíveis ações de planejamento e gestão para melhorar a qualidade da água dos reservatórios são apresentados.