Search Results (2)

Globally, soil acidification is becoming a serious environmental and ecological concern, posing a major threat to ecosystem functions and services. In order to clarifying the acidification mechanism, evaluating acidification risk, and reconditioning soil acidification, the effects of acidification on clay mineral composition and soil surface properties should be evaluated. In this study, the surface charge, specific surface area (SSA), species and content of clay minerals were investigated using the ion adsorption method, methylene blue method, and X-ray diffraction (XRD) for brown soil samples, which collected from Muping, Shandong Province, China. The results showed that the clay mineral species and content varied with the degree of acidification. A small amount of montmorillonite was found in weakly acidic soils, and gibbsite was found in strongly acidic soils. Furthermore, although illite, kaolinite, vermiculite, and chlorite were commonly found in soils with different acidification degrees, their content differed. The negative charge (CEC₈.₂), permanent negative charge (CEC_P), variable negative charge (CEC_V), and SSA values decreased with increasing acidification, while anion exchange capacity values (AEC) decreased. The change of CEC_V was caused by soil organic matter, and the change of CEC_P was caused by illite content, which accounted for the largest proportion in clay minerals of brown soil. Full article

Green belts are an urban planning approach meant to address urban sprawl and enhance resilience. Many Latin American cities located in arid lands would benefit from the green belt; however, little is known about the factors that determine green belt implementation in these regions. The purpose of this study is to fill this gap by examining the case of Hermosillo, Mexico, a rapidly growing city located in a desert environment with an envisioned green belt. A cross-disciplinary team worked with city officials and NGOs to implement a portion of the green belt by identifying suitable soils to locate and design a park within strategic segments of the green belt. However, rapid urbanization and the urgent need for recreational spaces led to the destruction of the landscape. A reflection on lessons learned stress the need for engagement with local communities and real estate developers to integrate social needs and market forces into the planning process for effective green belt implementation. Recommendations include a combination of bottom-up and top-down approaches, with efforts centered around housing development that provides the needed infrastructure and public space and is fully integrated to the rest of the city. For cities in arid lands, it becomes critical to adopt soft-path approaches for water resources management, assessment of soil conditions, and reconditioning of poor or polluted soils. To maintain the ecological functions of the protected land, efforts must be accompanied by policies that support the vision for the green belt, means to regulate gentrification, and resources allocated for enforcement. Full article