Abiotic transformation of estrogens in synthetic municipal wastewater: An alternative for treatment?

The abiotic transformation of estrogens, including estrone (E1), estradiol (E2), estriol (E3) and ethinylestradiol (EE2), in the presence of model vegetable matter was confirmed in this study. Batch experiments were performed to model the catalytic conversion of E1, E2, E3 and EE2 in synthetic wastewater. Greater than 80% reduction in the parent compounds was achieved for each target chemical after 72 h with the remaining concentration distributed between aqueous and solid phases as follows: 13% and 7% for E1, 10% and 2% for E2, 6% and 2% for E3, and 8% and 3% for EE2, respectively. Testosterone, androstenedione and progesterone were also monitored in this study, and their concentrations were found to be in agreement with initially spiked amount. Data collected under laboratory conditions provided the basis for implementing new abiotic wastewater treatment technologies that use inexpensive materials.     

Effects of petroleum contamination on soil microbial numbers, metabolic activity and urease activity

The influence of petroleum contamination on soil microbial activities was investigated in 13 soil samples from sites around an injection water well (Iw-1, 2, 3, 4) (total petroleum hydrocarbons (TPH): 7.5-78 mg kg⁻¹), an oil production well (Op-1, 2, 3, 4, 5) (TPH: 149-1110 mg kg⁻¹), and an oil spill accident well (Os-1, 2, 3, 4) (TPH: 4500-34 600 mg kg⁻¹). The growth rate constant (μ) of glucose stimulated organisms, determined by microcalorimetry, was higher in Iw soil samples than in Op and Os samples. Total cultivable bacteria and fungi and urease activity also decreased with increasing concentration of TPH. Total heat produced demonstrated that TPH at concentrations less than about 1 g kg⁻¹ soil stimulated anaerobic respiration. A positive correlation between TPH and soil organic matter (OM) and stimulation of fungi-bacteria-urease at low TPH doses suggested that TPH is bound to soil OM and slowly metabolized in Iw soils during OM consumption. These methods can be used to evaluate the potential of polluted soils to carry out self-bioremediation by metabolizing TPH.     

Impact of soil water regime on degradation and plant uptake behaviour of the herbicide isoproturon in different soil types

The environmental fate of the worldwide used herbicide isoproturon was studied in four different, undisturbed lysimeters in the temperate zone of Middle Europe. To exclude climatic effects due to location, soils were collected at different regions in southern Germany and analyzed at a lysimeter station under identical environmental conditions. ¹⁴C-isoproturon mineralization varied between 2.59% and 57.95% in the different soils. Barley plants grown on these lysimeters accumulated ¹⁴C-pesticide residues from soil in partially high amounts and emitted ¹⁴CO₂ in an extent between 2.01% and 13.65% of the applied ¹⁴C-pesticide. Plant uptake and ¹⁴CO₂ emissions from plants were inversely linked to the mineralization of the pesticide in the various soils: High isoproturon mineralization in soil resulted in low plant uptake whereas low isoproturon mineralization in soil resulted in high uptake of isoproturon residues in crop plants and high ¹⁴CO₂ emission from plant surfaces. The soil water regime was identified as an essential factor that regulates degradation and plant uptake of isoproturon whereby the intensity of the impact of this factor is strongly dependent on the soil type.     

Pesticide distribution in an agricultural environment in Argentina

An assessment of the off-site migration of pesticides from agricultural activity into the environment in the Neuquen River Valley was performed. The aim of this study was to evaluate the distribution of pesticides in several compartments of a small agricultural sub-catchment. Soil, surface water, shallow groundwater and drift deposition were analyzed for pesticide residues. Results showed the presence of some pesticide residues in soil, surface water and shallow groundwater compartments. The highest detection frequencies in water (surface and subsurface) were found for azinphos-methyl and chlorpyrifos (>70%). In terms of concentration, the highest levels were observed in shallow groundwater for azinphos methyl (22.5 μg/L) and carbaryl (45.7 μg/L). In the soil, even before the application period had started, accumulation of residues was present. These residues increased during the period studied. Spray drift during pesticide application was found to be a significant pathway for the migration of pesticide residues in surface water, while leaching and preferential flows were the main transport routes contributing to subsurface contamination.     

Water rights and legal pluralism: four contexts for negotiation

Increasing water scarcity is increasing pressure on water management institutions, particularly in the area of water rights. A common response is to formalise water tenure, one of several options for securing access and resolving conflicts concerning water allocation. This article looks at four contexts where negotiation, self-governance and concepts of legal pluralism may help improve water resource management. Existing users and potential new users need to negotiate before water resources are developed. Users can participate in forums with authority to solve basin management problems through self-governance. Negotiated water transfers offer an alternative to water acquisition by expropriation.     

The interplay of career involvement and goal conflicts: An eight-wave study with STEM professionals

Based on a “whole-life”-perspective and integrating theories of self-identity and resource management, the present longitudinal study examines the dynamic relationship between career involvement and conflicts between work and nonwork goals in a sample of 3095 German-speaking doctoral students and doctorate holders (37.0% women) from various STEM fields. We expected increases in goal conflicts to decrease career involvement, and simultaneously tested reciprocal relationships, that is, from involvement on conflicts. The random intercept cross-lagged panel model (RI-CLPM) was used to analyze within-person associations across eight measurement occasions (6-month time intervals) while controlling for between-person effects. At the between-person level, career involvement and goal conflicts were negatively correlated. At the within-person level, results showed negative cross-lagged effects from goal conflicts to career involvement as well as negative cross-lagged effects from career involvement to goal conflicts. This indicates that the interplay of goal conflicts and career involvement can result in either an upward or a downward spiral. Theoretical and practical implications are discussed.     

Herbivory reduces plant interactions with above- and belowground antagonists and mutualists

Herbivores affect plants through direct effects, such as tissue damage, and through indirect effects that alter species interactions. Interactions may be positive or negative, so indirect effects have the potential to enhance or lessen the net impacts of herbivores. Despite the ubiquity of these interactions, the indirect pathways are considerably less understood than the direct effects of herbivores, and multiple indirect pathways are rarely studied simultaneously. We placed herbivore effects in a comprehensive community context by studying how herbivory influences plant interactions with antagonists and mutualists both aboveground and belowground. We manipulated early-season aboveground herbivore damage to Cucumis sativus (cucumber, Cucurbitaceae) and measured interactions with subsequent aboveground herbivores, root-feeding herbivores, pollinators, and arbuscular mycorrhizal fungi (AMF). We quantified plant growth and reproduction and used an enhanced pollination treatment to determine if plants were pollen limited. Increased herbivory reduced interactions with both antagonists and mutualists. Plants with high levels of early herbivory were significantly less likely to suffer leaf damage later in the summer and tended to be less attacked by root herbivores. Herbivory also reduced pollinator visitation, likely due to fewer and smaller flowers, and reduced AMF colonization. The net effect of herbivory on plant growth and reproduction was strongly negative, but lower fruit and seed production were not due to reduced pollinator visits, because reproduction was not pollen limited. Although herbivores influenced interactions between plants and other organisms, these effects appear to be weaker than the direct negative effects of early-season tissue loss.     

The effects of biotic and abiotic factors on the spatial heterogeneity of alpine grassland vegetation at a small scale on the Qinghai–Tibet Plateau (QTP), China

Understanding the complex effects of biotic and abiotic factors on the composition of vegetation is very important for developing and implementing strategies for promoting sustainable grassland development. The vegetation–disturbance–environment relationship was examined in degraded alpine grasslands in the headwater areas of three rivers on the Qinghai–Tibet Plateau in this study. The investigated hypotheses were that (1) the heterogeneity of the vegetation of the alpine grassland is due to a combination of biotic and abiotic factors and that (2) at a small scale, biotic factors are more important for the distribution of alpine vegetation. On this basis, four transects were set along altitudinal gradients from 3,770 to 3,890 m on a sunny slope, and four parallel transects were set along altitudinal gradients on a shady slope in alpine grasslands in Guoluo Prefecture of Qinghai Province, China. It was found that biological disturbances were the major forces driving the spatial heterogeneity of the alpine grassland vegetation and abiotic factors were of secondary importance. Heavy grazing and intensive rat activity resulted in increases in unpalatable and poisonous weeds and decreased fine forages in the form of sedges, forbs, and grasses in the vegetation composition. Habitat degradation associated with biological disturbances significantly affected the spatial variation of the alpine grassland vegetation, i.e., more pioneer plants of poisonous or unpalatable weed species, such as Ligularia virgaurea and Euphorbia fischeriana, were found in bare patches. Environmental/abiotic factors were less important than biological disturbances in affecting the spatial distribution of the alpine grassland vegetation at a small scale. It was concluded that rat control and light grazing should be applied first in implementing restoration strategies. The primary vegetation in lightly grazed and less rat-damaged sites should be regarded as a reference for devising vegetation restoration measures in alpine pastoral regions.     

Social representations of socioenvironmental dynamics in extractive ecosystems and conservation practices with sustainable development: a bibliometric analysis

Environment, Development and Sustainability - Social representations necessarily originate from the interaction between individuals and groups in a social setting through communication and shared...     

Child passenger restraint use and emergency department--reported injuries: a special study using the National Electronic Injury Surveillance System-All Injury Program, 2004

INTRODUCTION: In 2004, more than 180,000 child passengers aged 相似文献