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The strategic goals of the United Nations and the Aichi Targets for biodiversity conservation have not been met. Instead, biodiversity has continued to rapidly decrease, especially in developing countries. Setting a new global biodiversity framework requires clarifying future priorities and strategies to bridge challenges and provide representative solutions. Hyper-arid, arid, and semi-arid lands (herein, arid lands) form about one third of the Earth's terrestrial surface. Arid lands contain unique biological and cultural diversity, and biodiversity loss in arid lands can have a disproportionate impact on these ecosystems due to low redundancy and a high risk of trophic cascades. They contain unique biological and cultural diversity and host many endemic species, including wild relatives of key crop plants. Yet extensive agriculture, unsustainable use, and global climate change are causing an irrecoverable damage to arid lands, with far-reaching consequences to the species, ground-water resources, ecosystem productivity, and ultimately the communities' dependant on these systems. However, adequate research and effective policies to protect arid land biodiversity and sustainability are lacking because a large proportion of arid areas are in developing countries, and the unique diversity in these systems is frequently overlooked. Developing new priorities for global arid lands and mechanisms to prevent unsustainable development must become part of public discourse and form the basis for conservation efforts. The current situation demands the combined efforts of researchers, practitioners, policymakers, and local communities to adopt a socio-ecological approach for achieving sustainable development (SDGs) in arid lands. Applying these initiatives globally is imperative to conserve arid lands biodiversity and the critical ecological services they provide for future generations. This perspective provides a framework for conserving biodiversity in arid lands for all stakeholders that will have a tangible impact on sustainable development, nature, and human well-being.

info:eu-repo/semantics/publishedVersion

We have investigated the physicochemical characteristics of chromium-nickel-containing waste from the production of corrosion-resistant steels and a doped alloy obtained by reduction smelting. This is necessary to determine the parameters that reduce the losses of Ni and Cr during the processing of doped oxide raw materials and using the resulting dopant. It was determined that the alloy with the O/C ratio in the charge in the range of 1.09–1.78 had the γ-Fe and Fe3C phases with alloying elements as substitutional atoms. At O/C=1.78, the phase composition predominantly consisted of γ-Fe with a weak manifestation of Fe3C. A phased O/C change in charge of 1.33 and 1.09 resulted in an increase in the emergence of Fe3C on diffractograms. The microstructure of the chrome-nickel-containing corrosion-resistant steels scale mixture is disordered with the presence of particles of different sizes and shapes. The content of the alloying elements Ni and Cr was 7.65 % wt. and 14.26 % wt., respectively, at the oxygen content at the level of 29.70 % wt. The microstructure of the doped alloy with a different O/C ratio in the charge had a clear manifestation of several phases, characterized by differences in the content of the main alloying elements. The Ni content in the studied areas of different phases varied within 1.41–20.90 % wt., Cr ‒ 1.27–32.90 % wt. According to research, the most acceptable O/C ratio in the charge is 1.78. In this case, reduction was achieved with predominance in the phase composition of γ-Fe with a relatively weak manifestation of residual carbon as the carbide component. In other words, we have determined the indicators for the processing of chromium-nickel-containing industrial wastes and the production of a doped smelting product with a relatively low carbon content. This expands the possibilities of resource saving using the obtained alloy with the replacement of a certain proportion of standard alloying materials in the smelting of carbon-limited steel grades.

The physical and chemical properties of products from the carbon-thermal reduction of oxide chromo-containing ore raw materials have been investigated. This is necessary to determine the parameters that reduce the loss of Cr in the processing of ore materials and the use of metallized chromium doping additives in steelmaking. It has been determined that the increase in processing temperature from 1,250 K to 1,450 K led to an increase in the manifestation of Cr23C6and (Cr, Fe)7C3. In this case, the diffraction maxima of Cr2O3corresponded to the trend of weakening and, having been treated at 1,450 K, had a residual character. Cr3C2on the diffractograms was only evident after processing at 1,250 K. The phase of the metallic Cr was traced in the samples after processing at 1,350 K and 1,450 K with the increased intensity of manifestation when the heating temperature rose. It has been determined that the microstructure of reduction products is heterogeneous with the presence of particles of different sizes and chemical compositions. The increase in the reduction temperature from 1,250 K to 1,350 K and 1,450 K and the development of reduction processes were accompanied by particle sintering with the formation of a spongy microstructure. We have detected regions that characterized inclusions and the phases where Cr content amounted to 65.10 % by weight, Fe ‒ to 16.13 % by weight. Some local areas with particles with a relatively high content of ore impurities and carbon have also been found. It follows from the results of our study that the most acceptable temperature for reduction is 1,450 K. In this case, the reduction is ensured with a predominance in the phase composition of the metal Cr and carbides (Cr, Fe)7C3and Cr23C6relative to the oxide component of Cr2O3. In this case, the lower residual carbon content was due to the higher efficiency of the reducer compared to other temperature regimes. The spongy microstructure allows for a faster dissolution compared to standard ferroalloys, thereby reducing the duration of smelting

It was determined that the oxidic tungsten concentrate is represented basically by CaWO4. Other phases have a fragmentary manifestation with a low intensity of the corresponding diffraction peaks. Microstructure is heterogeneous, disordered. Particles with presence of the accompanying ore impurities (molybdenum, calcium, silicon, iron, aluminum, fluorine and carbon) were found. The metallized tungsten concentrate after heat treatment at 1,250 K had a reduction degree of 21 % with a prevalence of CaWO4 in the phase composition. An increase in temperature to 1,350 K and 1,450 K provided a reduction degree of 69 % and 87 %, respectively. Under these conditions, a significant predominance of WC and W2C carbides was found in the phase composition. The presence of CaWO4 was of a residual nature with a relatively low intensity of manifestation. The microstructure of metallized tungsten concentrate was inhomogeneous with the presence of particles of various sizes and chemical compositions. As the reduction temperature increased, manifestation of the processes of sintering of particles was observed, especially clearly after treatment at 1,350 K and 1,450 K, Визначено, що оксидний вольфрамовий концентрат представлений в основному CaWO4. Мікроструктура розупорядкована. Проведення металізації вольфрамового концентрату при температурі теплової обробки 1350 K та 1450 K забезпечило ступінь відновлення 69 % та 87 % відповідно. Фазовий склад переважно представлений WC та W2C з деякою часткою CaWO4. Мікроструктура неоднорідна з проявом процесів спікання. Відсутність фаз схильних до сублімації забезпечує зменшення втрат W під час легування, Определено, что оксидный вольфрамовый концентрат представлен в основном CaWO4. Микроструктура разупорядоченная. Проведение металлизации вольфрамового концентрата при температуре тепловой обработки 1350 K и 1450 K обеспечило степень восстановления 69 % и 87 % соответственно. Фазовый состав преимущественно представлен WC и W2C с некоторой долей CaWO4. Микроструктура неоднородная с проявлением процессов спекания. Отсутствие фаз склонных к сублимации обеспечивает снижение потерь W во время легирования