Plastics, especially microplastics, are a diverse group of polymer-based particles, currently emerging as a global environmental threat—plastic pollution. An attempt was made to search for the presence of plastics in soils, particularly in a traditionally agricultural region such as Castilla y León (CYL). This study aimed to evaluate the use of plastics in agricultural soils in general, with an emphasis on CYL, by analyzing the present state and future perspectives on the addition of plastic waste to some agricultural soils in CYL. Surprisingly, many agricultural soils, including arable lands, irrigation, and especially greenhouse soils, receive plastic residues every day, which can lead to contaminants. By analyzing government data, we discovered that the volume of plastic waste from intensive agriculture is increasing (49,131 t in 2020) and that the current management system does not meet the needs of the sector. From this review, it can be inferred that plastics affect cultivated soils in CYL; this could affect both the economy and the soil itself and, by extension, the trophic food chain, food, and human health.

The vertical distribution of soil organic carbon (SOC), considered to be a key component of the carbon cycle, is still poorly understood in tropical highest mountain ecosystems such as the Andean paramo. The estimation of the SOC in the presence and absence of anthropic intervention, will help to define policies to mitigate CO2 emissions into the atmosphere from this ecosystem. The aim of this research was to determine soil organic carbon sequestration at three soil depths under two types of soil use in the paramo of Sumapaz, Colombia. The soil variations of pH, phosphorus, aluminum, bulk density, carbon sequestration, cation exchange capacity, texture and to estimate the vertical distribution of soil organic carbon SOC, were evaluated, respectively. Two sites were selected to establish the soil estimations according to soil use: natural vegetation cover and potato (Solanum tuberosum L.) crop. Samples were taken from 0-25, 25-50 and > 50 cm soil depths. Consequently, eight physical-chemical variables were analyzed in terms of the SOC sequestration estimated for each soil depth and soil. The averages for SOC under natural vegetation cover were: 188 tC.ha-1 to 25 cm, 183 tC.ha-1 to 50 cm, and 178 tC.ha-1 at soil depths below 50cm. For potato (Solanum tuberosum L.) crops, SOC sequestration were: 119 tC.ha-1 to 25 cm, 83 tC.ha-1 to 50 cm, and 71.8 tC.ha-1 at soil depths below 50cm. These results allow to support the soil management strategies that addressed to preserve SOC and regulate water level within the ecosystem of the Andean paramo.

An [H3KV12O27(AsO4)4]6−-isostructural ε-Keggin fragment anion, [H6KV12O27(VO4)(PO3CH3)3]5−, was photochemically prepared. This K+-capped anion is formally built of nine VIVO6 octahedra, three PO3C tetrahedra, and four VVO4 tetrahedra, one of the latter being a central VO43− group. The capping K+ cation lies on the C3 axis and links two adjacent anion, to form a linear chain of the anions along c-axis.

[Eu(H2O)8]3+ cations in [Eu(H2O)8]2[V10O28]·8H2O form an approximately square-antiprismatic configuration. This configuration provides another model for the Eu3+ aqua ion in aqueous solutions. The lifetime of the 5D0 state for [Eu(H2O)8]3+ is 0.13 ± 0.01 ms at 4.2K, leading to a validity of the luminescence lifetime method for the determination of the number of bonded water molecules (within the Eu-O distances of 2.5Å).

The well-known compound tetrakis(tert-butylammonium)-cyclo-tetrametavanadate (V), [(CH₃)₃CNH₃]₄[V₄O₁₂] (1h_RT), which crystallizes in the tetragonal I4/m space group, undergoes an irreversible solid state transformation upon heating, constituting one of the few examples in which the initial and the final stages are structurally characterized by sc-XRD. Now, we observed the ability of the same compound to undergo an additional single-crystal-to-single-crystal (SCSC) transformation upon thermal stimuli, but this time at low temperatures (153 K). Compound 1h_RT contains a discrete unprotonated [V₄O₁₂]⁴⁻ tetrahedral anion in which V and O bridging atoms are coplanar. In both phases, these tetrameric anions are linked through tert-butylammonium cations in an extensive network of hydrogen bonds, but at low temperatures, this phase loses its characteristic O-V-O coplanarity, with the resulting rearrangement of the crystal packing and hydrogen-bond network which provide its reversibility at low temperatures. Again, the initial and final stages have been characterized structurally by sc-XRD.