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71.
72.
Abstract

Chapter 28 of the UNCED agreement ‘Agenda 21’ asks for implementing sustainable development at the local level of government. Sweden is amongst the fore‐running nations in having responded quickly to these demands. Virtually all of Sweden's 288 municipalities have decided to embark on the Local Agenda 21 process. In this article, the progress so far and how LA21 has been interpreted at the local level are examined. The motives behind the process, the tensions between national and local policy making, and the role of municipal networks and NGOs are analysed. Four case studies of pioneer municipalities are used to illustrate how LA21 has sometimes inspired more far‐reaching goals at the local than at the national level, and the combination of economic development and marketing with environmental policy. It remains to be seen whether the most recent national government investment programme towards local projects for sustainable development will resolve the present conflicts between national goals and local priorities.  相似文献   
73.
Toxic heavy metals in air, soil and water are global problems that are growing threat to the environment. Therefore, the removal and separation of toxic and environmentally relevant heavy metal ions are a technological challenge with respect to industrial and environmental application. A promising process for the removal of heavy metal ions from aqueous solutions involves bonding the metals to a bonding agent (such as macromolecular species), and then separating the loaded agents from wastewater by separation processes such as membrane filtration. The choice of water-soluble macroligands remains important for developing this technology. The effects of type of complexing agent, pH value and applied pressure on retention coefficients of Zn(II) and Cd(II) complexes were investigated. At best operating conditions (pH=9.0, p=300kPa) using diethylaminoethyl cellulose, the removal of Cd(2+) and Zn(2+) was more than 95% and 99%, respectively.  相似文献   
74.
European forest policymaking is shaped by progressing European integration, yet with notable ideological divisions and diverging interests among countries. This paper focuses on the coalitional politics of key environmental forest issues: biodiversity conservation, timber legality, and climate protection policy. Combining the Advocacy Coalition Framework and the Shifting Coalition Theory, and informed by more than 186 key informant interviews and 73 policy documents spanning a 20-year timeframe, we examine the evolution of coalitional forest politics in Europe. We find that the basic line-up has remained stable: an environmental coalition supporting EU environmental forest policy integration and a forest sector coalition mostly opposing it. Still, strategic alliances across these coalitions have occurred for specific policy issues which have resulted in a gradual establishment of an EU environmental forest policy. We conclude with discussion of our findings and provide suggestions for further research.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01644-5.  相似文献   
75.
Manure-based soil amendments (herein “amendments”) are important fertility sources, but differences among amendment types and management can significantly affect their nutrient value and environmental impacts. A 6-month in situ decomposition experiment was conducted to determine how protection from wintertime rainfall affected nutrient losses and greenhouse gas (GHG) emissions in poultry (broiler chicken and turkey) and horse amendments. Changes in total nutrient concentration were measured every 3 months, changes in ammonium (NH4+) and nitrate (NO3?) concentrations every month, and GHG emissions of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) every 7–14 days. Poultry amendments maintained higher nutrient concentrations (except for K), higher emissions of CO2 and N2O, and lower CH4 emissions than horse amendments. Exposing amendments to rainfall increased total N and NH4+ losses in poultry amendments, P losses in turkey and horse amendments, and K losses and cumulative N2O emissions for all amendments. However, it did not affect CO2 or CH4 emissions. Overall, rainfall exposure would decrease total N inputs by 37% (horse), 59% (broiler chicken), or 74% (turkey) for a given application rate (wet weight basis) after 6 months of decomposition, with similar losses for NH4+ (69–96%), P (41–73%), and K (91–97%). This study confirms the benefits of facilities protected from rainfall to reduce nutrient losses and GHG emissions during amendment decomposition.

Implications: The impact of rainfall protection on nutrient losses and GHG emissions was monitored during the decomposition of broiler chicken, turkey, and horse manure-based soil amendments. Amendments exposed to rainfall had large ammonium and potassium losses, resulting in a 37–74% decrease in N inputs when compared with amendments protected from rainfall. Nitrous oxide emissions were also higher with rainfall exposure, although it had no effect on carbon dioxide and methane emissions. Overall, this work highlights the benefits of rainfall protection during amendment decomposition to reduce nutrient losses and GHG emissions.  相似文献   
76.
Violets from metal-enriched soils have controversially been described as both heavy-metal accumulators and excluders in the literature. The present study solves the issue for violets of the section Melanium (zinc violets, Viola lutea ssp. calaminaria and V. lutea ssp. westfalica; hartsease or wild pansy, Viola tricolor; and mountain pansy, V. lutea). The aims were to determine the concentrations of heavy metals in the soil and in the roots and shoots of field-collected plants, to evaluate the potential impact of colonisation by arbuscular mycorrhizal fungi on heavy-metal concentrations in the plant tissues, and to quantitatively define the localisation of the elements in root cross-sections. When these violets grow in low-metal soils, higher concentrations of the heavy metals were found in the roots and shoots than in the soil, whereas the opposite was seen in samples from high-metal soils. Under all field conditions examined, the roots of all of these species were colonised by arbuscular mycorrhizal fungi. However, V. tricolor was marginally colonised when the concentrations of Zn and P were higher in the soil. Determination of the spatial distribution of the elements in root cross-sections of these violets indicates tissue-specific deposition of elements within the vascular tissue, the cortex, and the rhizodermis. These data indicate that violets of the section Melanium are heavy-metal excluders.  相似文献   
77.
Quercetin is a dietary bioflavonoid used widely as a food supplement and is generally recognized as safe. The aim of this in vitro study was to examine the steroid hormone (progesterone and 17- β estradiol) release, proliferation (PCNA and cyclin B1) and apoptosis (caspase 3 and p53) of porcine ovarian granulosa cells after the addition of quercetin at concentrations 0.01, 0.1, 1, 10 and 100?μmol?L?1. Progesterone release was stimulated at the concentration 10?μmol?L?1. Quercetin neither had any impact on 17-β estradiol secretion nor on the presence of PCNA. However, a significant enhancement of the occurrence of cyclin B1 was noted except for the lowest concentration 0.01?μmol?L?1. Quercetin did not have any influence on the number of granulosa cells containing caspase 3, but at the concentration 10?μmol?L?1 it inhibited p53 occurrence. Results confirm the safety of quercetin in porcine ovarian granulosa cell model and further suggest its possible concentration-dependent influence on ovarian functions through pathway that may involve progesterone, cyclin B1 and p53.  相似文献   
78.
Carbamates (CB) are used as insecticides and some of them have been registered as human drugs. The mechanism of CB poisoning involves reversible inhibition of acetylcholine esterase. In the present study, we investigated changes in liver ultrastructure in rabbits (Oryctolagus cuniculus) which were administered bendiocarb for 3, 10, 20, and 30 days. Rabbits in all experimental groups received capsules of bendiocarb (96% Bendiocarb, Bayer, Germany) per os daily at a dose of 5 mg/kg of body weight, and after day 11 received the same dose every 48 h. The observed changes were only moderate, focal, and the effect on the liver was not uniform. On the third day of the experiment, injured hepatocytes had dilated bile capillaries with reduced microvilli. There were no visible alterations in the intercellular contacts. Nuclei of these cells were irregular in shape. Many hepatocytes showed considerable increase in the number of peroxisomes. On day 10 of the experiment, the number of peroxisomes was reduced. Other changes, such as dilated rough endoplasmic reticulum and proliferation of smooth endoplasmic reticulum were observed on day 20. The number of lipid droplets in hepatocytes gradually increased. Usually they were present in low numbers, but on day 30 of the experiment their number increased significantly. They coalesced and formed a single lipid droplet which changed the shape of the nuclei. The results presented in this study indicate that both short and long-term administration of bendiocarb affects the liver ultrastructure. At the same time we also observed rapid onset of regeneration of the damaged tissue through activation of hepatocytes and oval cells.  相似文献   
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