ABSTRACT
An environmental disaster caused by the rupture of a mining tailings dam has impacted a large area of the Rio Doce watershed in the Brazilian Atlantic Forest, resulting in unprecedented damage at spatial and temporal scales. The Atlantic Forest is one of the world's most important biodiversity hotspots. A long history of land use conversion has resulted in a highly fragmented landscape. Despite numerous restoration initiatives, these efforts have often biased criteria and use limited species assemblages. We conducted a comprehensive synthesis of the plant community in riparian forests along the Rio Doce watershed. Our work detailed vegetation composition (tree and sapling strata) and examined its relationship with edaphic and landscape factors, aiming to inform restoration projects with scientifically robust knowledge. A total of 4906 individuals from the tree strata and 4565 individuals from the sapling strata were recorded, representing a total of 1192 species from 75 families. Only 0.8% of the tree species and 0.5% of the sapling species occurred in all sampled sectors, with over 84% of the species occurring in a single watershed sector for both strata. We observed a high species heterogeneity modulated by turnover (92.3% in the tree, and 92.7% in the sapling strata) among sites. Overall, our research revealed a gradient of soil fertility influencing species composition across different strata. Additionally, we discovered that preserved landscapes had a positive impact on species diversity within both strata. The species exclusivity in the sampled sites and the high turnover rate imply the need to consider multiple reference ecosystems when restoring the watershed to reduce the risk of biotic homogenization. Finally, the reference ecosystems defined here serve as a basis for the selection of locally particular species in the implementation of restoration projects that aim to improve biodiversity, ecosystem services, and water security.
Subject(s)
Biodiversity , Environmental Restoration and Remediation , Forests , Brazil , Environmental Restoration and Remediation/methods , Conservation of Natural Resources/methods , Environmental Monitoring , Trees , RiversABSTRACT
The fate of HKUST-1 (Cu3(BTC)2, BTC = 1,3,5-benzenetricarboxylate) in the green Deep Eutectic Solvent (DES) reline (choline chloride/urea 1 : 2) was investigated, highlighting that not only reline can be used to make this MOF but also to transform it into another crystalline material. The synthesis of HKUST-1(reline) showing good textural properties and a particular rose morphology was indeed successfully achieved in this solvent. However, upon optimizing the reaction conditions such as concentration and metal/ligand ratio, it was found that another structure Cu2(BTC)Cl also forms. It was unequivocally demonstrated that, upon heating in reline, HKUST-1 converts to the non-porous chloride-incorporating material. Hence, a novel feature of DES in MOF synthesis is uncovered: its role as a structure-directing agent, triggering the transformation between two different MOF structures.
ABSTRACT
A series of nickel-decorated covalent organic frameworks, NiCl@RIO-12, were prepared using the post-synthetic modification strategy, that is, by reacting NiCl2 with pristine RIO-12 under alkaline conditions. Interestingly, they retained their crystallinity and the amount of nickel incorporated could be tuned from 3.6 to 25â wt % according to the reaction conditions. The incorporation of a higher amount of nickel in NiCl@RIO-12 consistently led to a lower Brunauer-Emmett-Teller surface area. Additionally, no agglomeration of nickel particles was found and a relatively homogeneous dispersion of nickel could be ascertained by SEM and TEM-EDS. The paramagnetic material exhibited promising catalytic activity in Suzuki-Miyaura cross-coupling under microwave heating. Thus, NiCl@RIO-12 notably demonstrated good thermal stability and its recyclability showed no substantial loss of activity after 3â cycles.
