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1.
Environ Res ; 218: 114961, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36495955

RESUMO

Due to their seemingly ubiquitous nature and links to environmental and human health problems, microplastics are quickly becoming a major concern worldwide. Artificial environments, such as those found in urban environments, represent some of the main sources of microplastic. However, very few studies have focused on the occurrence of microplastics in urban soils. The aim of the current research was to evaluate the microplastic contamination in urban soils from artificial and natural land uses throughout Coimbra city, Portugal. Sixty-seven spaces and ten land use areas were evaluated. The artificial land use areas were dumps, landfills, parking lots, industries and construction areas, and the natural land use areas were forests, urban parks, moors (wetlands), pastures and urban agricultural areas. Microplastic extraction was done by density separation. Quantification and size measurements of microplastics was carried out using a microscope. Polymer types were identified by µ-FTIR for 25% of the samples. The microplastic content ranged from 5 × 103 to 571 × 103 particles·kg-1, with a mean of 106 × 103 particle·kg-1. The green park was the land use with the highest concentration of microplastics (158 × 103 particle·kg-1) and the forest was the one with the lowest concentration (55 × 103 particle·kg-1). The landfill (150 × 103 particle·kg-1), industry (127 × 103 particle·kg-1) and dump (126 × 103 particle·kg-1) were the artificial spaces with the highest levels of microplastics. The main polymers detected were polypropylene and polyethylene, followed by polyvinyl chloride and rubber, and the main sizes measured between 50 and 250 µm. Our results indicate that natural spaces can contain higher amounts of microplastics as compared to artificial spaces in the urban environment. This suggests that microplastics are easily transported through the urban landscape and that urban green spaces can retain microplastics in their soils. Land use planning may present an opportunity to better control the levels of microplastics in urban environments.


Assuntos
Microplásticos , Poluentes Químicos da Água , Humanos , Plásticos , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Polímeros , Solo
2.
Environ Res ; 217: 114798, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36427636

RESUMO

The Guadiana Basin is a transnational basin, presenting historical contamination with potentially toxic metals (PTM), which origin can be both natural and anthropogenic. This study explores the use of a set of observational, chemical and ecotoxicological assays with Heterocypris incongruens, Vibrio fischeri, Pseudokirchneriella subcapitata, Thamnocephalus platyurus, identifying the most sensitive to be included in a toolbox to analyze the quality of freshwater sediments related to this type of contamination. The study included the analysis of a reservoir and streams sediments of Guadiana basin, in two consecutive years with different climate conditions 2017 (dry year) and 2018 (normal year). The results showed high chemical variability along the basin, with greater contamination with PTM in the reservoir sediments. The calculated Enrichment Factors (EF) indicated high anthropogenic contamination by Cd, followed by Pb (EF > 1.5). The geoaccumulation index (Igeo) revealed that the sediments were severely polluted with Cd, and slightly polluted with Pb and Cu, inducing a higher sublethal toxicity to Heterocypris incongruens. Among the parameters evaluated, and after the use of multivariate statistical techniques, the toolbox for assessing sediments quality, in similar climate and geological conditions, should include the analysis of: meteorology, land use/cover in the area, granulometry, organic matter content, PTM concentrations, contamination indices (e.g., Igeo and EF), and sublethal bioassays with H. incongruens (total sediment analysis) and Vibrio fisheri luminescence inhibition (pore water analysis).


Assuntos
Metais Pesados , Poluentes Químicos da Água , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Cádmio/análise , Chumbo/análise , Monitoramento Ambiental/métodos , Água Doce , Sedimentos Geológicos/análise , Metais Pesados/toxicidade , Metais Pesados/análise , Medição de Risco
3.
Environ Res ; 223: 115488, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36781012

RESUMO

Land use change alters the hydrochemical features, nutrient outputs, and community structure of aquatic photosynthetic organisms in watersheds and has an important impact on C, N, and P biogeochemical processes. In shallow water environments, sediments are the most important burial sites for C, N, and P; however, the factors underlying the control of their deposition by land use changes remain unclear. In this study, the relationship among hydrochemical features, aquatic photosynthetic organism community structure, and C, N, and P deposition in surface waters associated with different land uses was studied at the Shawan Karst Water-Carbon Cycle Test Site, Puding, SW China, by combining field monitoring and laboratory experiments performed over a complete hydrological year from September 2018 to August 2019. The results indicate that (1) OC and TN deposition showed small differences among ponds associated with five land uses, while TP was significantly higher in ponds associated with shrubland and grassland than in ponds of cultivated land, bare soil, and bare rock. (2) Cultivated land increased OC and TN deposition by increasing N and P output and planktonic algae biomass in surface waters, while grassland and shrubland ponds mainly by increasing DIC output and macrophyte biomass. (3) Compared with cultivated land, grassland and shrubland significantly enhanced TP deposition by promoting the deposition of calcium-bound P and biogenic P from macrophytes and their epiphytic algae in surface waters. In conclusion, the shift of cultivated land and bare soil to grassland and shrubland may be conducive to the formation of benign aquatic ecosystems and stabilization of C, N, and P sinks in karst shallow surface waters.


Assuntos
Ecossistema , Nitrogênio , Nitrogênio/análise , Solo/química , Carbono/análise , Água/química , China
4.
J Environ Manage ; 346: 118959, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37734215

RESUMO

Environmental crimes are a global issue due to the damage they cause to landscapes and ecosystems. This study focused on characterizing environmental crimes in the Canary Islands (Spain). Four categories of environmental crimes related to construction, mining and tilling, solid waste, and liquid waste) were defined and analysed. A total of 28 databases were generated, corresponding to each of the 7 major islands and each environmental crime typology. Each database was linked to information on land use and the socioeconomic and physical characteristics of the territory. For each database, firstly a descriptive statistical analysis was conducted, followed by the generation of a regularized Random Forest model with the aim of identifying characteristics that may be related to the location of environmental crimes. The results showed that, in most cases, proximity to residential accommodations, agricultural areas and industrial zones act as the main explanatory features of the distribution of environmental crimes. Furthermore, a marked pattern of concentration of environmental crimes in the coastal belt of the islands was observed, mainly associated with urban-tourist development since the 1960s and 1970s.


Assuntos
Efeitos Antropogênicos , Ecossistema , Humanos , Espanha , Crime , Ilhas
5.
Environ Geochem Health ; 45(10): 7255-7274, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37004580

RESUMO

Understanding the precise sources of heavy metals (HMs) in soil and the contribution of these sources to health risks has positive effects in terms of risk management. This study focused on the HMs in the soil of five land uses in an industrial and mining city. The sources of HMs in soils were identified, and the soil mineralogical characteristics and health risks of HMs were discussed. The results showed that the HMs (Cu, Zn, Ni, Cd, Pb) found in the soil of the five land uses were affected by human activities. For example, the Cu in grassland, gobi beach, woodland, green belt, and farmland is 22.3, 3.5, 22.5, 16.7, and 21.3 times higher than the soil background values in Gansu Province, respectively. The Positive Matrix Factorization model (PMF) results revealed that traffic emissions and industrial and agricultural activities were the primary sources of HMs in the soil, with industrial sources accounting for the largest share at 55.79%. Furthermore, various characteristics proved that the studied HMs were closely related to smelting products. Concentration-oriented health risk assessments showed that HMs in the different soil types held non-carcinogenic and carcinogenic risks for children and adults. Contamination source-oriented health risk assessments of children and adults found that industrial activities controlled non-carcinogenic and carcinogenic risks. This study highlighted the critical effects of smelting on urban soil and the contribution of pollution sources to health risks. Furthermore, this work is significant in respect of the risk control of HMs in urban soils.


Assuntos
Metais Pesados , Poluentes do Solo , Humanos , Carcinógenos , China , População do Leste Asiático , Monitoramento Ambiental/métodos , Metais Pesados/toxicidade , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/toxicidade , Poluentes do Solo/análise
6.
Reg Environ Change ; 23(3): 97, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37489177

RESUMO

Diverse agricultural land uses are a typical feature of multifunctional landscapes. The uncertain change in the drivers of global land use, such as climate, market and policy technology and demography, challenges the long-term management of agricultural diversification. As these global drivers also affect smaller scales, it is important to capture the traits of regionally specific farm activities to facilitate adaptation to change. By downscaling European shared socioeconomic pathways (SSPs) for agricultural and food systems, combined with representative concentration pathways (RCP) to regionally specific, alternative socioeconomic and climate scenarios, the present study explores the major impacts of the drivers of global land use on regional agriculture by simulating farm-level decisions and identifies the socio-ecological implications for promoting diverse agricultural landscapes in 2050. A hilly orchard region in northern Switzerland was chosen as a case study to represent the multifunctional nature of Swiss agriculture. Results show that the different regionalised pathways lead to contrasting impacts on orchard meadows, production levels and biodiversity. Increased financial support for ecological measures, adequate farm labour supplies for more labour-intensive farming and consumer preferences that favour local farm produce can offset the negative impacts of climate change and commodity prices and contribute to agricultural diversification and farmland biodiversity. However, these conditions also caused a significant decline in farm production levels. This study suggests that considering a broader set of land use drivers beyond direct payments, while acknowledging potential trade-offs and diverse impacts across different farm types, is required to effectively manage and sustain diversified agricultural landscapes in the long run. Supplementary information: The online version contains supplementary material available at 10.1007/s10113-023-02092-5.

7.
GeoJournal ; : 1-17, 2023 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38625199

RESUMO

The Jordan Valley's territorial extent is defined for this study as an elongated stretch of border area, located west of Jordan's boundary with the West Bank, Palestine. This region along with the West Bank was conquered by the Israeli Army during the June 1967 War and has been held by Israel since. Almost 88% of its 200,000 Palestinian population then living in the region were expelled and turned overnight into refugees in Jordan and elsewhere. In the subsequent 56 years since, the region, declared by Israel as a highly militarized zone, has often been discursively publicized as the front line of Israel's eastern defense. This paper seeks to refute such a notion that indirectly gave Israel justification to subject the remaining Palestinian inhabitants residing there (currently numbering ca. 60,000) to a harsh discriminatory regimen of surveillance and control under military occupation. At the same time, the Israeli government has over decades privileged the ca. 10,000 incoming Jewish settlers, now living in some 30 Israeli Jewish settlements in the Jordan Valley. Employing a grounded theory approach in our study provided an opportunity for the local Palestinians to have their voices heard, shedding needed analytical light on their difficult situation on the ground.

8.
J Environ Manage ; 298: 113514, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34391108

RESUMO

The effect of rainfall on the water quality of urban lakes is related to the surrounding land use types. Six lakes surrounded by business units (commercial lakes) and park green spaces (park lakes) in the central area of Beijing, China, were monitored between June 2013 and October 2015. A total of 638 water samples were obtained. The results showed that the water quality was generally worse in the rainy season than in the dry season, with the mean dissolved oxygen (DO) concentration declining by 25.1 %. Compared to the rise in DO of park lakes after rainfall, commercial lakes showed a decreased DO. The nitrate nitrogen (NO3--N) concentration decreased after rain, and that in commercial lakes decreased more than that in park lakes. Different from DO and NO3--N, the ammonia nitrogen (NH4+-N)), total suspended solids (TSS) and total phosphorus (TP) concentrations of the lakes increased obviously after rain. The values in park lakes increased 138 % (NH4+-N)), 120 % (TSS) and 69 % (TP) more than those in commercial lakes. Principal component analysis (PCA) results illustrated that green space was the main source of TSS and TP for urban lakes. Most of the nitrogen (N) comes from artificial impervious surfaces. These results will help target pollutant control for urban lakes.


Assuntos
Poluentes Químicos da Água , Qualidade da Água , China , Monitoramento Ambiental , Lagos , Nitrogênio/análise , Fósforo/análise , Chuva , Movimentos da Água , Poluentes Químicos da Água/análise
9.
Environ Monit Assess ; 192(7): 434, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32542519

RESUMO

Soil erosion affects agricultural production by reducing the area of rural properties and altering the dynamics of watersheds. Gullies are a complex and irregular type of erosion form that can reach large dimensions, and studying gullies to stabilize erosion processes is a challenge. This study aims to understand their environmental relationships as a basis for future research and to recover land degraded by soil erosion. We combined mapping techniques using geographic information system (GIS) with temporal evolution of land use and fractal dimensions of gullies using FracLac to determine the stability of gullies in a watershed in south Minas Gerais (Brazil). We used R software to apply linear regressions and tested the statistics to verify the compatibility of the model. Environmental characteristics of the watershed contribute to the formation of gullies, but human activities influence the deflagration of these features. The temporal evolution of the land use demonstrated that nearly 50% of the watershed was used as pastures throughout the years, which contributed to soil degradation. The evolution of the fractal dimension showed fluctuations over the years, indicating that the gullies are not stable. The regressions suggest that the vegetation, geology, land use, channel order, and curvature may influence the fractal dimensions of gullies. We concluded that human activity influences the evolution of gullies; the use of techniques such as vegetation measures can contribute to the stabilization of gullies. We also concluded that fractal analysis is an interesting tool for performing environmental evaluations of irregular and complex features, such as gullies.


Assuntos
Conservação dos Recursos Naturais , Sistemas de Informação Geográfica , Brasil , Monitoramento Ambiental , Fractais , Solo
10.
Ecotoxicol Environ Saf ; 169: 185-191, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30448701

RESUMO

The bulk depositions of trace metals to three land uses in the Yangtze River Delta are investigated based on the collected 154 precipitation samples from August 2015 to May 2017. The volume-weighted mean (VWM) concentrations of Ni, Cu, Zn, Cd, and Pb were 13.28, 5.32, 13.02, 0.33, and 10.53 µg L-1, and 12%, 16%, 3%, 11%, and 26% of precipitation events exceeded the limits in the Central Drinking-Water Source Area (GB3838-2002), respectively. Furthermore, the five metals varied significantly under urban, industrial, and rural land use conditions, indicating that these metal concentrations were greatly determined by local sources; lower concentrations were found in sea and local air masses than in air masses from inland trajectories. Combining the precipitation amounts, the bulk deposition fluxes of the five metals were 25.99, 25.47, 20.60, 10.40, 0.64 mg m-2 yr-1. By comparing the metal deposition fluxes in 98 studies across China, Ni and Pb deposition in the Yangtze River Delta was higher, while that of Cd and Zn was lower than their respective averages across China, indicating that Ni and Pb pollution should receive more attention in the study area. CAPSULE: Bulk/wet deposition fluxes of trace metals varied greatly among rural, industrial, and urban areas, and Pb and Ni showed severe pollution levels in the Yangtze River Delta.


Assuntos
Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Metais Pesados/análise , Rios/química , Oligoelementos/análise , China , Humanos , Indústrias , População Rural , População Urbana
11.
J Environ Manage ; 232: 999-1011, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33395769

RESUMO

To understand the distribution of soil elemental concentrations and their potential sources of trace metal contamination in the high-conservation Nee Soon freshwater swamp forest in Singapore, we analyzed samples from 227 surface and 35 subsurface (auger profiles) locations. Our assessment involved distribution maps, principle component analysis, cluster analysis, and correlation analysis of element concentrations determined from a mixed acid digestion and measurement on an ICP-MS. We found a distinct zonation in the distribution of several elements (Ba, Cr, Cu, Fe, Mn, Pb, Sr, Ti, V, and Zn) between the upper and lower catchment that gives an erroneous notion of widespread contamination in the lower catchment. We believe this zonation is natural, likely related to differences in the underlying geology. However, Cu, Pb, and Sb concentrations were greatly enriched by anthropogenic activities on military training lands in the lower catchment, firing ranges in particular. Barium, Sr, and Zn also appear to be enriched in the lower part of the catchment, possibly from anthropogenic activities including military activity and roads. Although soils in the catchment are not highly contaminated, isolated areas with high concentrations of Cu, Pb and Sb may warrant management attention given the sensitive nature of the urban forest, which includes the last remaining fresh water swamp forest in Singapore.

12.
J Environ Manage ; 246: 203-213, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31176982

RESUMO

To support sustainable urban planning and the design of water pollution mitigation strategies, the spatial and temporal trends of water quality in urban streams needs to be further understood. This study analyses over ten years of surface water quality data from 53 upstream catchments (20 of them predominated by a single type of land use) and two lowland sites across Greater Melbourne, Australia. We evaluated the impact of various catchment characteristics, especially urban land uses, on spatial and temporal urban water quality trends. Here, we focused on common urban pollutants: total suspended solids (TSS), total phosphorous (TP), total nitrogen (TN), zinc (Zn), copper (Cu) and nickel (Ni). Site median nutrient and heavy metal concentrations were negatively correlated with the catchment's elevation and its average annual rainfall. Further analysis shows that such trends were driven by the geographical pattern of Melbourne - i.e. low-laying sites tend to have less rainfall and be more urbanised. Only median concentrations of heavy metals (Zn and Cu) were correlated to catchment imperviousness. Further characterising of the urban environment was done into specific land uses (residential, industrial and commercial), yet median concentrations of all pollutants were not significantly correlated with land uses. This is because simple metrics, such as land use proportions, do not adequately reflect the significant variability in pollution sources that can exist even within the same land use type. Indeed, our temporal analysis found that the water quality difference between catchments with similar land uses is likely caused by their site-specific pollutant sources (construction and illegal discharge) and environmental management actions (wastewater management actions) regardless of similarities in land use. A 3-stage urbanisation cycle (development, operation and renewal) is suggested to further explain the urban water quality variance, but more data from small areas of an urban catchment is required to directly understand the unique impact of each urbanisation stage on water quality.


Assuntos
Rios , Poluentes Químicos da Água , Austrália , Monitoramento Ambiental , Qualidade da Água
13.
Environ Monit Assess ; 192(1): 58, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31858272

RESUMO

The reduction of riparian vegetation around aquatic environments causes several physicochemical alterations and favors the entry of pesticides via surface runoff. Such changes have negative effects on aquatic organisms. In this study, we evaluated histopathological alterations in gills of Astyanax bifasciatus to test the hypothesis that more severe histopathological alterations occur in gills of fish from streams with higher agricultural impact from the surrounding area. The specimens were collected by electrofishing in seven streams of the lower Iguaçu basin between August 2015 and February 2016. The gills were processed according to routine histological methods and examined by light microscopy. The histopathological alterations, mainly stage II (lamellar aneurysm and total fusion of lamellae), were observed in fish collected in streams with higher agricultural activity. In these streams, the histopathological index indicated slight to moderate organ lesions. In contrast, in streams with more vegetation cover, fish collected presented stage I histopathological alterations (lamellar edema and lamellar hyperplasia), and the HI indicated normal functioning of the gills. In addition, chloride and acid mucous cells were more abundant in the gills of fish collected in rural streams. Our findings demonstrate that more severe histopathological alterations were registered in fish collected from streams with intense agricultural activity in the surrounding area. Therefore, it highlights that vegetation cover around the streams is a positive force for the conservation and health of aquatic organisms.


Assuntos
Monitoramento Ambiental/métodos , Peixes/crescimento & desenvolvimento , Florestas , Brânquias/efeitos dos fármacos , Praguicidas/toxicidade , Rios/química , Poluentes Químicos da Água/toxicidade , Agricultura , Animais , Brasil , Brânquias/patologia , Praguicidas/análise , Alimentos Marinhos , Estações do Ano , Clima Tropical , Poluentes Químicos da Água/análise
14.
Ecotoxicol Environ Saf ; 164: 722-731, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30176561

RESUMO

The quality of soils under different land uses is getting deteriorated throughout the world due to various anthropogenic activities. This deterioration is highly complex in riverine floodplain areas due to contamination by multiple point and non-point sources and change in seasons. Therefore, a study was conducted to analyze seasonal (pre and post-monsoon) variations in physico-chemical characteristics, contents of metal(loid)s (Al, As, Cd, Cr, Co, Cu, Fe, Mn, Mo, Ni, Pb, Sb and Zn) in riverine floodplain soils under three land uses (agricultural, riverbank and roadside) from areas around the rivers Beas and Sutlej in Punjab, India. Further, analysis was done to assess the ecological and genotoxic risks (Allium cepa genotoxicity assay) posed by metal(loid)s in these soils. It was observed that soil samples under the three land uses were slightly alkaline (pre-monsoon) to acidic (post-monsoon) in nature with sandy texture and low soil organic matter. The levels of most metal(loid)s increased in post-monsoon soil samples under the three land uses, which was attributed to increase in soil organic matter, silt and clay contents in post-monsoon samples due to precipitation, flooding and sedimentation. The ecological Risk Index (58.3-104.5) and Modified Risk Index (145.2-178.9) calculated to analyze the level of ecological risks of metal(loid)s revealed that As, Cd and Sb posed moderate to considerable ecological risks in the agricultural and roadside soils in both seasons. Allium cepa genotoxicity assay indicated that the metal(loid)s in studied soils can cause genotoxic effects in biological systems. Therefore, various steps such as reduction in use of agrochemicals, promotion of organic agricultural methods and decontamination of soils using techniques such as phytoremediation etc must be taken to ensure reduction and containment of metal(loid)s in such riverine floodplain areas.


Assuntos
Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Fenômenos Químicos , Dano ao DNA , Ecologia , Monitoramento Ambiental , Concentração de Íons de Hidrogênio , Índia , Medição de Risco , Estações do Ano
15.
Disasters ; 41(2): 228-257, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27238758

RESUMO

Claims of environmental injustice, human neglect, and racism dominated the popular and academic literature after Hurricane Katrina struck the United States in August 2005. A systematic analysis of environmental injustice from the perspective of the survivors remains scanty or nonexistent. This paper presents, therefore, a systematic empirical analysis of the key determinants of Katrina-induced environmental injustice attitudes among survivors in severely affected parishes (counties) in Louisiana and Mississippi three years into the recovery process. Statistical models based on a random sample of survivors were estimated, with the results revealing significant predictors such as age, children in household under 18, education, homeownership, and race. The results further indicate that African-Americans were more likely to perceive environmental injustice following Katrina than their white counterparts. Indeed, the investigation reveals that there are substantial racial gaps in measures of environmental injustice. The theoretical, methodological, and applied policy implications of these findings are discussed.


Assuntos
Atitude , Tempestades Ciclônicas , Desastres , Meio Ambiente , Justiça Social/psicologia , Sobreviventes/psicologia , Adolescente , Adulto , Negro ou Afro-Americano/psicologia , Negro ou Afro-Americano/estatística & dados numéricos , Idoso , Atitude/etnologia , Pesquisa Empírica , Feminino , Humanos , Louisiana , Masculino , Pessoa de Meia-Idade , Mississippi , Classe Social , Sobreviventes/estatística & dados numéricos , População Branca/psicologia , População Branca/estatística & dados numéricos , Adulto Jovem
16.
J Environ Manage ; 172: 2-9, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26905446

RESUMO

Mineral-associated organic carbon (MOC), that is stabilized by fine soil particles (i.e., silt plus clay, <53 µm), is important for soil organic carbon (SOC) persistence and sequestration, due to its large contribution to total SOC (TSOC) and long turnover time. Our objectives were to investigate how climate, soil type, soil texture, and agricultural managements affect MOC contributions to TSOC in China. We created a dataset from 103 published papers, including 1106 data points pairing MOC and TSOC across three major land use types: cropland, grassland, and forest. Overall, the MOC/TSOC ratio ranged from 0.27 to 0.80 and varied significantly among soil groups in cropland, grassland, and forest. Croplands and forest exhibited significantly higher median MOC/TSOC ratios than in grassland. Moreover, forest and grassland soils in temperate regions had higher MOC/TSOC ratios than in subtropical regions. Furthermore, the MOC/TSOC ratio was much higher in ultisol, compared with the other soil types. Both the MOC content and MOC/TSOC ratio were positively correlated with the amount of fine fraction (silt plus clay) in soil, highlighting the importance of soil texture in stabilizing organic carbon across various climate zones. In cropland, different fertilization practices and land uses (e.g., upland, paddy, and upland-paddy rotation) significantly altered MOC/TSOC ratios, but not in cropping systems (e.g., mono- and double-cropping) characterized by climatic differences. This study demonstrates that the MOC/TSOC ratio is mainly driven by soil texture, soil types, and related climate and land uses, and thus the variations in MOC/TSOC ratios should be taken into account when quantitatively estimating soil C sequestration potential of silt plus clay particles on a large scale.


Assuntos
Sequestro de Carbono , Carbono , Solo/química , Agricultura , Silicatos de Alumínio , Carbono/análise , Carbono/química , China , Argila , Clima , Florestas , Pradaria
17.
Ecotoxicol Environ Saf ; 112: 87-95, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25463858

RESUMO

Road-deposited sediment (RDS) is a valuable environmental medium for characterizing contamination of metals in urban areas and the associated risks to human health. A total of 62 RDS samples were collected for metal test in four urban areas in a medium size city in eastern China. The areas that represented different land uses consisted of intense traffic area (ITA), commercial area (CA), residential area (RA), and riverside park area (RPA). The effects of particle size and different land uses on metal contamination and health risk were the major focus in this study. The test results showed that RDS in ITA appeared to have higher metal content, enrichment factor (EF), ecological risk index (RI), and the non-cancer and cancer risks than in the other areas. The metal contamination and health risk increased inversely with particle size. The particles less than 63 µm were found to be most critical in development of metal contamination and health risk. The EF was measured to be greater than 2.0 in the four areas, indicating a moderate enrichment. The measured RI ranged between 50 and 200, indicating considerable to moderate risks. The non-cancer risk for children was high in the four areas but was low for adults in all test areas except in ITA. The cancer risk of Cr for children was high in all test areas. Based on the test results, the contamination control and management for metals in RDS shall focus on the effects from such factors as particles (<63 µm) and the land use for intense traffic (ITA).


Assuntos
Poluentes Atmosféricos/toxicidade , Sedimentos Geológicos/análise , Metais/toxicidade , Material Particulado/toxicidade , Poluentes do Solo/toxicidade , Poluentes Atmosféricos/análise , China , Cidades , Meio Ambiente , Monitoramento Ambiental , Humanos , Metais/análise , Tamanho da Partícula , Material Particulado/análise , Medição de Risco , Poluentes do Solo/análise
18.
Huan Jing Ke Xue ; 45(5): 2848-2858, 2024 May 08.
Artigo em Zh | MEDLINE | ID: mdl-38629547

RESUMO

The application of biomarkers to study the molecular composition of soil organic matter (SOM) can be used to analyze the source and degradation of SOM and reveal the stability mechanism of soil organic carbon (SOC) at the molecular level. In order to further clarify the effects of different land use patterns (farmland, grassland, and forest) on the molecular composition of SOM, the changes in molecular composition of organic matter (free lipids, cutin, suberin, and lignin) on a global scale were studied using a meta-analysis method. The results showed that there were significant differences in the molecular composition of organic matter under different land use patterns. The contents of free lipids (n-alkanes, n-alkanols, n-alkanoic acids, and cyclic lipids), cutin, and lignin phenols in forest soil were significantly higher than those in grassland and farmland. There was no significant difference in the content of suberin between grassland and forest soil. The ratio of suberin to cutin in grassland was the highest, with an average of 2.96, and the averages of farmland and forest were 1.68 and 2.21, respectively. The ratio of syringic acid to syringaldehyde (Ad/Al)S and the ratio of vanillic acid to vanillin (Ad/Al)V of farmland soil were the largest, which were 1.25 and 1.58, respectively, and were significantly higher than those in grassland (0.46 and 0.69) and forest (0.78 and 0.7). The results of correlation analysis showed that in farmland soil, suberin was significantly correlated with mean annual precipitation (MAP) and clay; cutin was significantly correlated with clay; and lignin was significantly correlated with mean annual temperature (MAT), MAP, sand, and bulk density. In grassland soil, total free lipids were significantly correlated with MAP and bulk density; suberin and cutin were significantly correlated with MAT and MAP; and lignin was significantly correlated with MAP, pH, sand, and bulk density. However, only lignin was significantly correlated with MAP and sand in forest soils. Overall, the contents of SOC and molecular components in forest soil were higher under the three land use practices, and the contribution of plant roots to SOM in grassland soil was greater. In farmland soil, the degradation of lignin was accelerated due to human farming activities. Future research should focus on the regulation of soil physicochemical properties and climatic conditions on the molecular composition of SOM.

19.
Sci Total Environ ; 923: 171437, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38447735

RESUMO

Human actions can damage the ecosystems and affect the services depending on them, with ample detrimental consequences. In earlier studies, the Conservation Use Potential (PCU) framework proved useful in assessing the capacity for aquifer recharge, suitable land uses and resistance to erosion at the river basin scale. On the other hand, the joint analysis of PCU and land uses allowed identifying the adequacy of current uses in relation to suitability (natural uses) in various basins. This was especially useful from the management perspective in basins with environmental conflicts, where current uses differed from suitability, because the PCU indicated how and where the conflicts should be mitigated. Besides the use as management tool, the PCU has potential to shed light over environmental issues such as ecosystem services, but that was not tempted so far. The aim of this work was therefore to bridge that knowledge gap and frame the PCU's application from the standpoint of Ecosystem Services (ES) assessment. We demonstrated how the PCU could be used to improve provision (recharge), support (sustainable agriculture) and regulation (resistance to erosion) services in a specific basin with land use conflicts (the Upper Rio das Velhas basin, located in Minas Gerais, Brazil), through the planning of suitable uses. It was noted that the studied basin is mostly composed of Very Low, Low and Medium potentials. These classes occur because steep slopes, fragile soils and lithologies with high denudation potential and low nutrient supply dominate in the basin. On the other hand, urban sprawl has a negative impact on all ES, while maintaining agricultural areas with appropriate management can effectively regulate erosion. As per the current results, the premise of using the PCU as joint management-environmental tool was fully accomplished, and is recommended a basis for public policy design and implementation in Brazil and elsewhere.

20.
Data Brief ; 54: 110521, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38783964

RESUMO

The dynamic soil properties for soil health (DSP4SH) is a Science of Soil Health Initiative that was designed to collect, process, and publicize scientifically rigorous datasets that inform sound indicators and interpretations. The Soil and Plant Science Division of the United States Department of Agriculture - Natural Resources Conservation Service (USDA-NRCS) and university cooperators collected a suite of standardized soil health metrics across eight states (Oregon, Washington, Kansas, Minnesota, Illinois, Connecticut, North Carolina, and Texas) within five soil survey regions (Northwest, North Central, Northeast, Southeast, and South Central). The DSP4SH database provides a substantial dataset of soil health metrics assessed. The dataset is composed of dynamic soil properties (DSP) data collected from each management system or ecological state represented by one to three independent plot replicates. Each plot has a minimum of three pedons. Nine groups from the DSP4SH monitoring network provided datasets used in developing the database. The submitted data includes 37 laboratory measured parameters, 60 variables of layer/horizon descriptions, 41 variables for laboratory analysis conducted at the Kellogg Soil Survey laboratory, and 12 variables for the management systems. An additional 31 variables were developed for site or plot description. Additional variables were developed to normalize the dataset. In preparation for DSP assessment, all tables (except for dataset from KSSL lab) were categorized by management system or ecological state. The categories were business as usual (BAU), the reference condition (Ref) and the soil health management (SHM). The overarching goal of DSP4SH phase 1 and 2 dataset publication is to promote increased accessibility, further analysis of the data, and overall understanding of the benefits of surveying dynamic soil properties for soil health.

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