Mountain Goc is one of the regions with the highest water potential in Central Serbia (Yugoslavia), with specific annual runoff of 12-17 l/s per square km. Upper part of the catchment area of the Gvozdacka River has 111 springs, on the surface of 13.3 square km. 33 springs has volume yield from 0.5 to 2.5 l/s, with physical and chemical parameters of high water quality. These springs never dry up, even during years with low amount of precipitation. The upper part of the catchment area of the Gvozdacka River is under association Abieti-Fagetum, which is one of the worthiest in Serbia (Yugoslavia). Besides annual amount of precipitation, characteristics of soil, hydro-geological attributes of rock masses, influence of vegetation on processes of interception and evapotranspiration, which are very important factors for preservation of springs and their volume yield, also the system of forest ecosystems management. Not adequate measures in exploitation of forests lead to decreasing of volume yield of springs, and often to their disappearing.

Globally distributed karstic soils are characterized by the high accumulation of heavy metal(loid)s, such as Cd. Biogeochemistries and transferability of metal(loid)s in such soils are notably different from that in soils of anthropogenic pollution as evidenced by increasing studies about rice and maize. To solve the question about metal(loid) background and transferability in the system of karstic soils and crops with underground fruits, we designedly collected 246 paired soil–peanut seed samples in a world-famous karstic region in Southwestern China covering an area of 98,700 km². The concentrations of eight regulatory metal(loid)s (Cd, As, Cr, Cu, Hg, Ni, Pb, and Zn) in soil samples exceeded current standards to different degrees, demonstrating a typical high background. However, the transferability of metal(loid)s from soils to peanut seeds is quite low, resulting in a low exceedance rate of metal(loid)s (Cd, 12.2% and Pb, 1.2%) in seeds (“seed metal(loid)s”), in accordance with the results that metal(loid)s in soils mostly distributed in the inert/residual fractions. Based on the distinct response characteristics of peanut seed metal(loid)s to soil status from rice/maize grain metals, a model was further developed for effectively predicting the concentration of Cd in peanut seeds. Collectively, this study provides a basis for the assessment of soil environmental quality and safety zoning of upland field in karst areas.

Human activities such as dams disturb the structure and function of wetlands, triggering large soil CO₂ and CH₄ emissions. However, controls over field CO₂ and CH₄ emissions and their carbon isotopic signatures in reservoir wetlands are not yet fully understood. We investigated in situ CO₂ and CH₄ emissions, the δ¹³C values of CO₂ and CH₄, and associated environments in the saturated and drained states under four elevations (i.e., the water column, <147 m, permanent inundation area without plants; the low, 145–160 m, frequently flooded area with revegetation; the high, 160–175 m, rarely flooded area with revegetation; and the upland area as the control, >175 m, nonflooded area with original plants) in the Three Gorges Reservoir area. The CO₂ emissions was significantly higher in high elevation, and they also significantly differed between the saturated and drained states. In contrast, the CH₄ emissions on average (41.97 μg CH₄ m⁻² h⁻¹) were higher at high elevations than at low elevations (22.73 μg CH₄ m⁻² h⁻¹) during the whole observation period. CH₄ emissions decreased by 90% at low elevations and increased by 153% at high elevations from the saturated to drained states. The δ¹³C of CH₄ was more enriched at high elevations than in the low and upland areas, with a more depleted level under the saturated state than under the drained state. We found that soil CO₂ and CH₄ emissions were closely related to soil substrate quality (e.g., C: N ratio) and enzyme activities, whereas the δ¹³C values of CO₂ and CH₄ were primarily associated with root respiration and methanogenic bacteria, respectively. Specifically, the effects of the saturated and drained states on soil CO₂ and CH₄ emissions were stronger than the effect of reservoir elevation, thereby providing an important basis for assessing carbon neutrality in response to anthropogenic activities.

The aims of this study were to determine type and application rate of composted animal manure to optimize sweet potato yield relative to N₂O emissions from upland soils. To this end, the study was conducted on upland soils amended with different types and rates of composted animal manure and located at two geographically different regions of South Korea. Field trials were established at Miryang and Yesan in South Korea during the sweet potato (Ipomoea batatas) growing season over 2 years: 2017 (Year 1) and 2018 (Year 2). Three composted animal manures (chicken, cow, and pig) were applied at the rates of 0, 10, and 20 Mg ha⁻¹ to upland soils in both locations. In both Years and locations, manure type did not affected significantly cumulative N₂O emissions from soil during the sweet potato growing season or the belowground biomass of sweet potato. However, application rate of animal manures affected significantly the cumulative N₂O emission, nitrogen (N) in soil, and belowground biomass of sweet potato. An increase in cumulative N₂O emission with application rates of animal manures was related to total N and inorganic N concentration in soil. The belowground biomass yield of sweet potato but also the cumulative N₂O emission increased with increasing application rate of composted animal manures up to 7.6 and 16.0 Mg ha⁻¹ in Miryang and Yesan, respectively. To reduce N₂O emission from arable soil while increasing crop yield, composted animal manures should be applied at less than application rate that produce the maximum belowground biomass of sweet potato.

Oil sands activities north of Fort McMurray, Alberta, have intensified in recent years with a concomitant debate as to their environmental impacts. The Regional Aquatics Monitoring Program and its successor, the Joint Canada-Alberta Implementation Plan for Oil Sands Monitoring (JOSM), are the primary aquatic programs monitoring this industry. Here we examine sediment data (collected by Ekman grabs) to investigate trends and sources of polycyclic aromatic hydrocarbons (PAHs), supplementing these data with sediment core studies. Total PAH (ΣPAH) concentrations were highest at Shipyard Lake (6038 ± 2679 ng/g) in the development center and lower at Isadore's Lake (1660 ± 777 ng/g) to the north; both lakes are in the Athabasca River Valley and lie below the developments. ΣPAH concentrations were lower (622–930 ng/g) in upland lakes (Kearl, McClelland) located further away from the developments. ΣPAH concentrations increased at Shipyard Lake (2001–2014) and the Ells River mouth (1998–2014) but decreased in nearshore areas at Kearl Lake (2001–2014) and a Muskeg River (2000–2014) site. Over the longer term, ΣPAH concentrations increased in Kearl (1934–2012) and Sharkbite (1928–2010) Lakes. Further (200 km) downstream in the Athabasca River delta, ΣPAH concentrations (1029 ± 671 ng/g) increased (1999–2014) when %sands were included in the regression model; however, 50 km to the east, concentrations declined (1926–2009) in Lake Athabasca. Ten diagnostic ratios based on anthracene, phenanthrene, fluoranthene, pyrene, benz[a]anthracene, chrysene, indeno[123-cd]pyrene, dibenz[a,h]anthracene, dibenzothiophene and retene were examined to infer spatial and temporal trends in PAH sources (e.g., combustion versus petrogenic) and weathering. There was some evidence of increasing contributions of unprocessed oil sands and bitumen dust to Shipyard, Sharkbite, and Isadore's Lakes and increased combustion sources in the Athabasca River delta. Some CCME interim sediment quality guidelines were exceeded, primarily in Shipyard Lake and near presumed natural bitumen sources.

The occurrence and spatial distribution of polychlorinated naphthalenes (PCNs) were investigated in sediments, upland and paddy soils from the Liaohe River Basin. Concentrations of ΣPCNs were in the range of 0.33–12.49 ng g⁻¹ dry weight (dw) in sediments and 0.61–6.60 ng g⁻¹ dw in soils, respectively. Tri-CNs and tetra-CNs were the dominating homologues. An increasing trend of PCNs contamination was found in sediments with the rivers flowing through industrial areas and cities. Soils collected near cities exhibited higher abundance of PCNs than that of rural areas. The distribution of PCNs was related to the local industrial activities, rather than total organic carbon. Positive matrix factorization (PMF) was used for the source apportionment of PCNs in sediments and paddy soils. The result of PMF indicated that PCNs in sediments and paddy soils were mainly from the industrial processes, with additional contributions from the historical use of Halowax 1014 and atmospheric deposition.

Nitrogen (N) deposition impacts natural and semi-natural ecosystems globally. The responses of vegetation to N deposition may, however, differ strongly between habitats and may be mediated by the form of N. Although much attention has been focused on the impact of total N deposition, the effects of reduced and oxidised N, independent of the total N deposition, have received less attention. In this paper, we present new analyses of national monitoring data in the UK to provide an extensive evaluation of whether there are differences in the effects of reduced and oxidised N deposition across eight habitat types (acid, calcareous and mesotrophic grasslands, upland and lowland heaths, bogs and mires, base-rich mires, woodlands). We analysed data from 6860 plots in the British Countryside Survey 2007 for effects of total N deposition and N form on species richness, Ellenberg N values and grass:forb ratio. Our results provide clear evidence that N deposition affects species richness in all habitats except base-rich mires, after factoring out correlated explanatory variables (climate and sulphur deposition). In addition, the form of N in deposition appears important for the biodiversity of grasslands and woodlands but not mires and heaths. Ellenberg N increased more in relation to NHx deposition than NOy deposition in all but one habitat type. Relationships between species richness and N form were habitat-specific: acid and mesotrophic grasslands appear more sensitive to NHx deposition while calcareous grasslands and woodlands appeared more responsive to NOy deposition. These relationships are likely driven by the preferences of the component plant species for oxidised or reduced forms of N, rather than by soil acidification.

Homologue and congener profiles of PCDD/Fs in eels, passive sampler and sediment extracts from the Burrishoole, a rural upland catchment on the western Irish seaboard were compared with potential PCDD sources. ΣPCDD/F levels in eels ranged from 2.9 to 25.9 pg g−1 wet weight, which are elevated compared to other Irish locations. The OCDD congener dominated the pattern of ΣPCDD/Fs in all matrices from Burrishoole. Passive samplers were successfully deployed to identify for the first time the presence in the water column of PCDD/Fs and dimethoxylated octachlorodiphenyl ether (diMeOoctaCDE), impurities found in pentachlorophenol (PCP) production. Principal component analysis (PCA) identified similarities between PCDD/F profiles in technical PCP mixtures and environmental samples from the Burrishoole region. Results strongly suggest residual PCDD contamination associated with historic local use of a dioxin contaminated product in the catchment area, with pentachlorophenol a strong candidate.

Nitrous oxide emission factors (N₂O-EF, percentage of N₂O–N emissions arising from applied fertilizer N) for cropland emission inventories can vary with agricultural management, soil properties and climate conditions. Establishing a regionally-specific EF usually requires the measurement of a whole year of N₂O emissions, whereas most studies measure N₂O emissions only during the crop growing season, neglecting emissions during non-growing periods. However, the difference in N₂O-EF (ΔEF) estimated using measurements over a whole year (EFwy) and those based on measurement only during the crop-growing season (EFgₛ) has received little attention. Here, we selected 21 studies including both the whole-year and growing-season N₂O emissions under control and fertilizer treatments, to obtain 123 ΔEFs from various agroecosystems globally. Using these data, we conducted a meta-analysis of the ΔEFs by bootstrapping resampling to assess the magnitude of differences in response to management-related and environmental factors. The results revealed that, as expected, the EFwy was significantly greater than the EFgₛ for most crop types. Vegetables showed the largest ΔEF (0.19%) among all crops (0.07%), followed by paddy rice (0.11%). A higher ΔEF was also identified in areas with rainfall ≥600 mm yr⁻¹, soil with organic carbon ≥1.3% and acidic soils. Moreover, fertilizer type, residue management, irrigation regime and duration of the non-growing season were other crucial factors controlling the magnitude of the ΔEFs. We also found that neglecting emissions from the non-growing season may underestimate the N₂O-EF by 30% for paddy fields, almost three times that for non-vegetable upland crops. This study highlights the importance of the inclusion of the non-growing season in the measurements of N₂O fluxes, the compilation of national inventories and the design of mitigation strategies.

Keeping in view the expanding environmental pollution and irrigation water deficit, a pot experiment was performed for the upland (Huyou2, Hanyou737) and paddy rice cultivars (Taigeng8; Yixiang2292), to study soil liming effects on methane (CH₄) and nitrous oxide (N₂O) emission, bioavailability and accumulation of Cd, Pb in upland and paddy rice. Upland rice reduced 90% of soil CH₄ emission as compared to paddy conditions. Soil CH₄ emission decreased by 45% and 39% with dolomite, and it reduced by 35% and 33% with lime treatment both in upland and paddy conditions, respectively. Soil N₂O emission decreased by 44% and 52% with dolomite, and with the lime application, it was reduced by 37% and 44% for both upland and paddy conditions respectively. Reduction in soil DTPA-extractable Cd was between 37-53% and 43–80% with dolomite and 16–37% and 24–72% Cd decreased with lime application in upland and paddy conditions respectively. Soil DTPA-extractable Pb reduced by 27–44% and 25–53% with dolomite and 16–40% and 11–42% with soil-applied lime in upland and paddy conditions, respectively. Cd accumulation in rice grain was decreased by 47–88% and 62–79% with dolomite and 31–86% and 45–52% reduction by lime application in upland and paddy rice respectively. Rice grain Pb reduced by 58–91% and 66–78% with dolomite application and 32–71% and 44–71% with lime in upland and paddy rice, respectively. Our results showed that soil liming significantly reduced soil N₂O and CH₄ emission and Cd, Pb accumulation in rice grain, but dolomite was more effective as compared to lime. Altogether, results of this study suggest that upland rice can be cultivated in CdPb polluted soils with least soil CH₄ emission. Cd and Pb toxicity, accumulation, and N₂O emission in upland rice can be minimized by soil liming of 3 g kg⁻¹ and optimizing the nutrients composition of the soil.