Study on soil quality in different functional zones of Sofia region

Abstract

The present study deals with examining the condition of urban soils and their potential to deliver soil-related regulating ecosystem services concerning the level of anthropogenic pressure in different functional zones of Sofia, Bulgaria. Analyses of data for selected characteristics of superficial 0-10 cm soil layer of urban soils were performed. Soils were sampled from 30 experimental plots within a geo-referred network covering urban and peri-urban territories. The concentrations of heavy metals Cu, Zn, Pb and Fe were analysed to determine the level of pollution, while soil pH, cation-exchange capacity (CEC), total carbon and total nitrogen content were used as indicators for assessing the regulating ecosystem service “soil quality”. The results demonstrate the differences in the potential of four functional zones – green zones, industrial zones, residential zones and zones for urban agriculture, to regulate and maintain “soil quality”. The purpose of the assessment is to outline the zones with the potential for implicating mitigation measures in urban and peri-urban zones, based on maps of soil quality, which contributes to focusing more attention on the protection and restoration of urban soils, to reduce soil pollution and to increase the reuse of urban soils.

Methodological Approaches and Literature Analysis in the Study of Soil Carbon in Urban Green Spaces: A Systematic Review

“…Their soil carbon data provide carbon information, despite being the central theme of the research. For example, studies that focused on soil properties [22,29,[62][63][64][65][66][67][68][69][70][71][72][73][74], ecosystem services [2,19,31,43,[75][76][77][78] or aspects such as urban sprawl and land use change [26,77,79,80].…”

“…As mentioned in the introduction, a predominant focus on soil carbon has been studied in the form of SOC [1,2,4,[16][17][18][19]21,22,[26][27][28][29]43,45,[48][49][50][51][52][54][55][56][57][58][59][60][61][62]65,67,[69][70][71][72]74,76,[80][81][82][83] and in the form of Total Carbon [25,50,51,63,65,66,68,73,75,[77]…”

“…In terms of the methodology, there majority of the articles reported in situ sampling in soils of urban green areas. Many of these studies were based solely on in situ measurements [1,2,16,18,21,22,29,43,49,[52][53][54]56,[58][59][60][61][62][63][64][65][66][67][68][70][71][72][73][74][75][76]78,80,81,83,85]. Some researchers complement this approach with other methods such as remote sensing imagery [4,26,27,57], open data [26,28,45,79,84], logarithmic modelling [17,31,48,50,…”

“…Some authors focused only on the investigation of specific green spaces [1,[16][17][18]22,25,27,49,[51][52][53][54][55][56]59,63,[65][66][67]71,78,79]. On the contrary, others authors chose to compare soil carbon derived from different types of green space [2,4,19,21,28,29,31,43,45,[48][49][50]57,60,69,70,[73][74][75][76][83][84][85].…”

Sustainability of Organic Farming from a Global Perspective: A Critical Analysis of Soil Types and Fertility Status of Organically Managed vs. Chemicalized Vegetable Fields of South India

“…Perhaps the current study is the rst comparative analysis of pH variations over organic and chemicalized elds over the broad South Indian tropical climatic zone. Although the majority of elds (about 70%) showed a pH of medium soil quality range of 6.5 to 7.5 (Todorova & Zhiyanski, 2023), statistical analysis reveals that the variation in pH over seven speci c soil types in the region is signi cant and varies widely from 5.43 (Pampadumpara soil series) to 8.88 (Koratty soil series). Naturally, soil series and orders may be distinct in pH (Bonfante & Bouma, 2015).…”