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71.
Kathleen Neumann Peter H. Verburg Berien Elbersen Elke Stehfest Geert B. Woltjer 《Agriculture, ecosystems & environment》2011,140(1-2):88-101
The European livestock sector has changed rapidly in the recent past and further changes are expected in the near future due to reforms in the European Common Agricultural Policy (CAP), increasing environmental concerns and changing consumer awareness. We developed a multi-scale modeling approach for exploring spatial and temporal dynamics of livestock distribution by accounting for drivers at different spatial scales. Such approach can provide a basis for environmental impact assessments of livestock farming at broad spatial scales. Assessment of change in both quantity and location was made for six livestock types. Four contrasting scenarios were applied ranging from globalization to regionalization, as well as from low regulation levels and dominance of market forces towards a higher degree of governmental regulation. National level livestock numbers as calculated by a macro-economic model were spatially distributed at the landscape scale according to the scenario assumptions considering biophysical, socio-economic, and political forces. Results indicate for most of the old European Union (EU) member countries a decrease in livestock numbers. In the new EU member countries sheep, goats and pigs are expected to decline while beef cattle and poultry are expected to grow. Livestock densities are expected to increase both within and outside current livestock hotspot regions in absence of environmental legislations. Environmental pressure as result of high livestock densities may, however, also remain in regulated scenarios where environmental policies are implemented and income support remains stable over time due to path dependencies in the livestock sector. But contrary to the non-regulated scenario it is less likely that new areas with high risk of negative environmental impacts due to livestock farming will develop. 相似文献
72.
Projecting Land-Use Change and Its Consequences for Biodiversity in Northern Thailand 总被引:5,自引:0,他引:5
Rapid deforestation has occurred in northern Thailand over the last few decades and it is expected to continue. The government
has implemented conservation policies aimed at maintaining forest cover of 50% or more and promoting agribusiness, forestry,
and tourism development in the region. The goal of this paper was to analyze the likely effects of various directions of development
on the region. Specific objectives were (1) to forecast land-use change and land-use patterns across the region based on three
scenarios, (2) to analyze the consequences for biodiversity, and (3) to identify areas most susceptible to future deforestation
and high biodiversity loss. The study combined a dynamic land-use change model (Dyna-CLUE) with a model for biodiversity assessment
(GLOBIO3). The Dyna-CLUE model was used to determine the spatial patterns of land-use change for the three scenarios. The
methodology developed for the Global Biodiversity Assessment Model framework (GLOBIO 3) was used to estimate biodiversity
intactness expressed as the remaining relative mean species abundance (MSA) of the original species relative to their abundance
in the primary vegetation. The results revealed that forest cover in 2050 would mainly persist in the west and upper north
of the region, which is rugged and not easily accessible. In contrast, the highest deforestation was expected to occur in
the lower north. MSA values decreased from 0.52 in 2002 to 0.45, 0.46, and 0.48, respectively, for the three scenarios in
2050. In addition, the estimated area with a high threat to biodiversity (an MSA decrease >0.5) derived from the simulated
land-use maps in 2050 was approximately 2.8% of the region for the trend scenario. In contrast, the high-threat areas covered
1.6 and 0.3% of the region for the integrated-management and conservation-oriented scenarios, respectively. Based on the model
outcomes, conservation measures were recommended to minimize the impacts of deforestation on biodiversity. The model results
indicated that only establishing a fixed percentage of forest was not efficient in conserving biodiversity. Measures aimed
at the conservation of locations with high biodiversity values, limited fragmentation, and careful consideration of road expansion
in pristine forest areas may be more efficient to achieve biodiversity conservation. 相似文献
73.
This paper presents an assessment of the potential impact of the EUs biofuel directive on European land use and biodiversity. In a spatially explicit analysis, it is determined which ecologically valuable land use types are likely to be directly replaced by biofuel crops. In addition, it is determined which land use types may be indirectly replaced by biofuel crops through competition over land between biofuel and food crops. Four scenarios of land use change are analyzed for the period 2000–2030 while for each scenario two policy variants are analyzed respectively with and without implementation of the biofuel directive. The results indicate that the area of semi natural vegetation, forest and High Nature Value farmland directly replaced by biofuel crops is small in all scenarios and differs little between policy variants. The direct effects of the directive on European land use and biodiversity therefore are relatively minor. The indirect effects of the directive on European land use and biodiversity are much larger than its direct effects. The area semi natural vegetation is found to be 3–8% smaller in policy variants with the directive as compared to policy variants without the directive. In contrast, little difference is found between the policy variants with respect to the forest area. The results of this study show that the expected indirect effects of the directive on biodiversity are much greater than its direct effects. This suggests that indirect effects need to be taken explicitly into account in assessing the environmental effects of biofuel crop cultivation and designing sustainable pathways for implementing biofuel policies. 相似文献
74.
Godinho RM Wolterbeek HT Verburg T Freitas MC 《Environmental pollution (Barking, Essex : 1987)》2008,151(2):318-325
This experiment compares the short and long time element accumulation behaviour of transplants of Flavoparmelia caperata lichen thalli and total deposition in an atmospheric polluted area. It was found that lichens exposed for a short time behaved differently from lichens in cumulative exposition suggesting the presence of acclimatization behaviour. The lichen transplant elemental content does not unequivocally represent the average or cumulative environmental availability of the exposure period. Reflection characteristics depend on the element and the lichen physiological conditions. Good correlations between lichen elemental contents and total deposition were obtained when a physiological lichen parameter was introduced in a mathematical model, suggesting that metabolically mediated accumulation is important. 相似文献
75.
Filling and cleaning of pesticide sprayers presents a potential risk of pollution of soil and water. Three different solutions for handling sprayers have been suggested: Filling and cleaning in the field, filling and cleaning on hard surfaces with collection of the waste water, and filling and cleaning on a biobed, which is an excavation lined with clay and filled with a mixture of chopped straw, sphagnum and soil with turf on top, and with increased sorption capacity and microbial activity for degradation of the pesticides. In the present study the degradation and leaching of 21 pesticides (5 g of each) was followed in an established full-scale model biobed. Percolate was collected and analysed for pesticide residues, and the biobed material was sampled at three different depths and analysed by liquid chromatography double mass spectrometry (LC-MSMS). During the total study period of 563 days, no traces of 10 out of 21 applied pesticides were detected in the percolate (detection limits between 0.02 and 0.9 μg l−1) and three pesticides were only detected once and at concentrations below 2 μg l−1. During the first 198 days before second application, 14% of the applied herbicide bentazone was detected in the leachate with maximum and mean concentrations of 445 and 172 μg l−1, respectively. About 2% of the initial mecoprop and fluazifop dose was detected in the percolate, with mean concentrations of 23 μg l−1, while MCPA and dimethoate had mean concentrations of 3.5 and 4.7 μg l−1, respectively. Leachate concentrations for the remaining pesticides were generally below the detection limit (0.02–0.9 μg l−1, below 1% of applied). Sorption studies of five pesticides showed that compounds with a low Kd value appeared in the leachate. After 169 days, all pesticides in the biobed profile were degraded to a level below 50% of the calculated initial dose. Pesticides with Koc values above 100 were primarily found in the uppermost 10 cm and degraded slowest due to the low bioavailability. The 11 most degradable pesticides were all degraded such that less than 3% remained in the biobed after 169 days.
Following second pesticide application of the biobed, leachate was sampled 215 and 365 days after the treatment. This showed the same pesticides to be leached out and at concentrations comparable to those of the first treatment. The same pesticides as after the first treatment were retained in the biobed. 相似文献
76.
Landscape representations based on land cover databases differ significantly from the real landscape. Using a land cover database with high uncertainty as input for emission inventory analyses can cause propagation of systematic and random errors. The objective of this study was to analyze how different land cover representations introduce systematic errors into the results of regional N2O emission inventories. Surface areas of grassland, ditches, and ditch banks were estimated for two polders in the Dutch fen meadow landscape using five land cover representations: four commonly used databases and a detailed field map, which most closely resembles the real landscape. These estimated surface areas were scaled up to the Dutch western fen meadow landscape. Based on the estimated surface areas agricultural N2O emissions were estimated using different inventory techniques. All four common databases overestimated the grassland area when compared to the field map. This caused a considerable overestimation of agricultural N2O emissions, ranging from 9% for more detailed databases to 11% for the coarsest database. The effect of poor land cover representation was larger for an inventory method based on a process model than for inventory methods based on simple emission factors. Although the effect of errors in land cover representations may be small compared to the effect of uncertainties in emission factors, these effects are systematic (i.e., cause bias) and do not cancel out by spatial upscaling. Moreover, bias in land cover representations can be quantified or reduced by careful selection of the land cover database. 相似文献
77.
78.
This paper presents a Life Cycle Assessment of a hemp fibre reinforced component for automotive parts. Its aim is to identify the optimisation strategies within the product system and also provide decision support for automotive engineers for or against the employment of renewable raw materials within the production process. The investigated life cycle contains the agricultural cultivation of the fibre plant, the method of harvesting and the processing of the crop. The analysis includes the further processing of the fibre, i.e. the manufacturing of the fibre composite matrix, on which the production of form press components for the automotive industry is based. Manufacturing the required preproducts is also taken into account. The differences of energy demand (CED) and emission amount during the use phase of a passenger car and different disposal options for the end of the life cycle (deposition or incineration) are assessed as well. It is shown that the natural fibre composite is ecologically preferable to the injection moulded reference as the results of the Eco-indicator 95 method show. Optimisation is necessary for the epoxy-resin-hardener system, although the cultivation of fibre plants is ecologically an insignificant process regarding the system boundaries. The weight difference and resulting energy savings during the use phase of a car reveal further advantages of a fibre panel. 相似文献
79.
Archetypical patterns and trajectories of land systems in Europe 总被引:1,自引:0,他引:1
Levers Christian Müller Daniel Erb Karlheinz Haberl Helmut Jepsen Martin Rudbeck Metzger Marc J. Meyfroidt Patrick Plieninger Tobias Plutzar Christoph Stürck Julia Verburg Peter H. Verkerk Pieter J. Kuemmerle Tobias 《Regional Environmental Change》2018,18(3):715-732
Regional Environmental Change - Assessments of land-system change have dominantly focused on conversions among broad land-use categories, whereas intensity changes within these categories have... 相似文献
80.
Root uptake of enteric pathogens and subsequent internalization has been a produce safety concern and is being investigated as a potential route of pre-harvest contamination. The objective of this study was to determine the ability of hepatitis A virus (HAV) and the human norovirus surrogate, murine norovirus (MNV), to internalize in spinach and green onions through root uptake in both soil and hydroponic systems. HAV or MNV was inoculated into soil matrices or into two hydroponic systems, floating and nutrient film technique systems. Viruses present within spinach and green onions were detected by RT-qPCR or infectivity assays after inactivating externally present viruses with Virkon®. HAV and MNV were not detected in green onion plants grown up to 20 days and HAV was detected in only 1 of 64 spinach plants grown in contaminated soil substrate systems up to 20 days. Compared to soil systems, a drastic difference in virus internalization was observed in hydroponic systems; HAV or pressure-treated HAV and MNV were internalized up to 4 log RT-qPCR units and internalized MNV was shown to remain infectious. Understanding the interactions of human enteric viruses on produce can aid in the elucidation of the mechanisms of attachment and internalization, and aid in understanding risks associated with contamination events. 相似文献