Resilience Perception of a Mining Town in Eastern Amazonia: A Case Study of Canaã Dos Carajás, Brazil.

The ability of communities to react to risks and disturbances is for their balance, development, and sustainability. The concept of resilience provides a way to think about policies and actions for future changes in socioeconomic and ecological-environmental systems. This paper analyzes, in the context of mining, the perception of the resilience of Canaã dos Carajás population in Pará State, Brazilian Amazon. The methodology involved face-to-face interviews based on a structured questionnaire conducted on a sample of 140 residents stratified from 11 social actors in the Canaã community. This approach allowed the evaluation of resilience perception using 26 interview statements derived from six resilience theories. Our multivariate analysis found that the level of residents' perception of resilience was reasonable (with an average score of 3.04 ± 0.22 using a Likert scale, with a Cronbach's alpha of 0.788). The interviewees pointed out one positive and five negative factors that influenced the level of resilience in Canaã. According to residents' perceptions, the resilience of Canaã dos Carajás was moderate but could have been improved with more economic diversification, more infrastructure, and less inequality in access to services and participation in decision-making. The considered most relevant themes were problems caused by mining in the municipality, quality of life issues, difficulties dealing with change after the arrival of mining, and economic problems. This study contributes to the literature because it used theories as a conceptual orientation for the development of a resilience scale to measure resilience at the community level in the context of large-scale mining.

Geography is essential for reproductive isolation between florally diversified morning glory species from Amazon canga savannahs.

The variety, relative importance and eco-evolutionary stability of reproductive barriers are critical to understanding the processes of speciation and species persistence. Here we evaluated the strength of the biotic prezygotic and postzygotic isolation barriers between closely related morning glory species from Amazon canga savannahs. The flower geometry and flower visitor assemblage analyses supported pollination by the bees in lavender-flowered Ipomoea marabaensis and recruitment of hummingbirds as pollinators in red-flowered Ipomoea cavalcantei. Nevertheless, native bee species and alien honeybees foraged on flowers of both species. Real-time interspecific hybridization underscored functionality of the overlap in flower visitor assemblages, questioning the strength of prezygotic isolation underpinned by diversification in flower colour and geometry. Interspecific hybrids were fertile and produced offspring in nature. No significant asymmetry in interspecific hybridization and hybrid incompatibilities among offspring were found, indicating weak postmating and postzygotic isolation. The results suggested that despite floral diversification, the insular-type geographic isolation remains a major barrier to gene flow. Findings set a framework for the future analysis of contemporary evolution of plant-pollinator networks at the population, community, and ecosystem levels in tropical ecosystems that are known to be distinct from the more familiar temperate climate models.

Natural history of the narrow endemics Ipomoea cavalcantei and I. marabaensis from Amazon Canga savannahs.

Amazon comprises a vast variety of ecosystems, including savannah-like Canga barrens that evolved on iron-lateritic rock plateaus of the Carajás Mountain range. Individual Cangas are enclosed by the rain forest, indicating insular isolation that enables speciation and plant community differentiation. To establish a framework for the research on natural history and conservation management of endemic Canga species, seven chloroplast DNA loci and an ITS2 nuclear DNA locus were used to study natural molecular variation of the red flowered Ipomoea cavalcantei and the lilac flowered I. marabaensis. Partitioning of the nuclear and chloroplast gene alleles strongly suggested that the species share the most recent common ancestor, pointing a new independent event of the red flower origin in the genus. Chloroplast gene allele analysis showed strong genetic differentiation between Canga populations, implying a limited role of seed dispersal in exchange of individuals between Cangas. Closed haplotype network topology indicated a requirement for the paternal inheritance in generation of cytoplasmic genetic variation. Tenfold higher nucleotide diversity in the nuclear ITS2 sequences distinguished I. cavalcantei from I. marabaensis, implying a different pace of evolutionary changes. Thus, Canga ecosystems offer powerful venues for the study of speciation, multitrait adaptation and the origins of genetic variation.