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261.
Förster M Helms Y Herberg A Köppen A Kunzmann K Radtke D Ross L Itzerott S 《Environmental management》2008,41(4):584-598
The use of renewable energy in Europe offers the possibility of reducing greenhouse gas emissions, and contributes to energy
security and independence. With the reform of the Common Agricultural Policy (CAP) and a variety of recently introduced national
directives supporting renewable energy sources in the European Union, the economic attractiveness of bioenergy production
has distinctly increased. This article combines an economic evaluation of biomass production with site-related natural conditions
of the Havelland region, situated in the north-east area of Germany. Two methods for evaluating site-specific potential biomass
yields were compared. For three example biomass crops, evaluations of yield estimations at agricultural lots for site-optimized
suitability (SOS) and conventional suitability (CS) were carried out. Both modelling approaches were compared. The results
of the GIS modelling indicate that the financial support for increasing the use of renewable energy with the German feed-in
system, called Erneuerbare-Energien-Gesetz (EEG), will possibly lead to an increased cultivation of crops with high biomass
output. This monocultural orientation of farming practices and the negative effects on the ecosystem could act in opposition
to other environmental initiatives of the EU. The outputs of the SOS analysis show that high biomass production could be integrated
into environmental policy proposals. Therefore, new EU policy should take modified subsidies into consideration in order to
avoid developing conflicts between small-scale changes in landscape ecosystems caused by large-scale transformations in energy
policy. 相似文献
262.
Agricultural expansion and deforestation are spatial processes of land transformation that impact on landscape pattern. In
peninsular Malaysia, the conversion of forested areas into two major cash crops—rubber and oil palm plantations—has been identified
as driving significant environmental change. To date, there has been insufficient literature studying the link between changes
in landscape patterns and land-related development policies. Therefore, this paper examines: (i) the links between development
policies and changes in land use/land cover and landscape pattern and (ii) the significance and implications of these links
for future development policies. The objective is to generate insights on the changing process of land use/land cover and
landscape pattern as a functional response to development policies and their consequences for environmental conditions. Over
the last century, the development of cash crops has changed the country from one dominated by natural landscapes to one dominated
by agricultural landscapes. But the last decade of the century saw urbanization beginning to impact significantly. This process
aligned with the establishment of various development policies, from land development for agriculture between the mid 1950s
and the 1970s to an emphasis on manufacturing from the 1980s onward. Based on a case study in Selangor, peninsular Malaysia,
a model of landscape pattern change is presented. It contains three stages according to the relative importance of rubber
(first stage: 1900–1950s), oil palm (second stage: 1960s–1970s), and urban (third stage: 1980s–1990s) development that influenced
landscape fragmentation and heterogeneity. The environmental consequences of this change have been depicted through loss of
biodiversity, geohazard incidences, and the spread of vector-borne diseases. The spatial ecological information can be useful
to development policy formulation, allowing diagnosis of the country’s “health” and sustainability. The final section outlines
the usefulness of landscape analysis in the policy-making process to prevent further fragmentation of the landscape and forest
loss in Malaysia in the face of rapid economic development.
相似文献
Adnan A. HezriEmail: |
263.
于2010年6月—10月每月对青木关地下河水进行监测,利用15N同位素技术并结合水化学指标,分析地下河的水化学特征以及硝态氮来源的时空变化特征。结果表明,地下河出口丁家龙洞硝态氮质量浓度(5.08 mg/L)比入口天池2号点(0.842 mg/L)高6倍多。天池2号点处δ15N为-0.705%~+0.706%,主要受到人造化肥和天然土壤矿化的有机氮的影响,总体变化幅度不大,地下水受外界影响较小。出口丁家龙洞处的δ15N为-2.15%~+3.78%,平均值为+1.01%,总体值高,且变化幅度大。 相似文献
264.
Quintin L. Williams Jr. Author Vitae Bruce H. Alexander Author Vitae Author Vitae Timothy R. Church 《Journal of Safety Research》2010,41(1):31-37
Background
With more than a million youth living on agricultural operations, it is important for parents to understand the consequences of bystander injuries that children experience in these environments. We identified the childhood injuries for bystander status and compared the severity of these injuries to the working children in the Regional Rural Injury Study-II (RRIS-II).Methods
RRIS-II followed 16,546 children (∼ 85% of eligible) from rural communities in the Midwest for two six-month recall periods in 1999 and 2001. Demographic, injury, and exposure data were collected through comprehensive computer-assisted telephone interviews. Child injuries were cataloged using narrative scenarios into four categories: (a) directly work-related; (b) indirectly work-related; (c) non-working accomplice; and (d) non-working attendant; the latter three all being bystander categories. Poisson regression modeling was used to calculate rates of bystander injuries. Frequencies were used for comparison of severity measures.Results
Among the 463 child injuries (aged < 20 yrs), 102 were bystander injuries. Of the bystander-related injuries, 14 were identified as indirectly work-related (working bystanders), 27 as non-working accomplice (passengers/tag-alongs), and 60 as non-working attendant (playing on the operation). The overall rate of bystander injuries was 6.4 per 1,000 people, 95% CI (5.0, 8.1). Males, compared with females, had more than twice the injury rate (8.7; 95% CI 6.4-11.8, and 3.9; 95% CI 2.7-5.7, per 1,000 people, respectively). Bystanders in this population had more severe injuries with 4% having life-threatening circumstances; of these, 4% of the accomplices and 2% of the attendants subsequently died.Conclusions
Children who live or work on agricultural operations are vulnerable to many hazards. Therefore, this study examined child injuries and found a clear difference in the consequences of these injuries between working-related and bystanding-related injuries.Impact on Industry
Unlike occupations such as construction and mining, where laws and organizations have been created for the protection of bystanders, agricultural bystanders have remained unprotected and have had to face the consequent injury and death outcomes. As public health professionals considering these risks, it is necessary that we work to develop more intervention studies and continue to propose suggestive guidelines for child safety in these environments so as to challenge family traditions and possibly spark public policies that will give further protection to this population. 相似文献265.
Improved understanding of temporal and spatial Phosphorus (P) discharge variations is needed for improved modelling and prioritisation
of abatement strategies that take into account local conditions . This study is aimed at developing modelling of agricultural
Phosphorus losses with improved spatial and temporal resolution, and to compare the accuracy of a detailed process-based model
with a rainfall-runoff coefficient-based model. The process-based SWAT model (Soil and Water Assessment Tool) was implemented
for five river basins in central Sweden, and results compared with the rainfall-runoff coefficient-based model WATSHMAN (Watershed
Management System) for one of these river basins. Parameter settings and attribute values were adapted to Scandinavian soil
conditions, crops and management practices. Model performance regarding flow dynamics was overall satisfactory. Comparable
results were achieved at several scales. The modelled P load was of high accuracy for the days when monitoring data were available
for validation, generally once a month. Modelled monthly P load did not fit as well with averaged monthly monitoring load
values, mainly since monthly monitoring often partly or entirely misses the peak flows. The comparison of SWAT and WATSHMAN
gave slightly better results for the process-based model (SWAT). Better spatial resolution for input data such as Soil-P content
and agricultural management practices will be required to reach modelling results that enable identification of measures adapted
to local conditions. 相似文献
266.
Agricultural causes of desertification risk in Minqin, China 总被引:1,自引:0,他引:1
This study uses statistical modeling techniques to develop a desertification risk index (RI) for Minqin County, Gansu Province, China. Twenty socio-economic factors were selected and compared with the RI results to explore the spatial and temporal variability of desertification risk in the study area and to identify possible local driving forces behind desertification risk. The explanatory factors were different in 1988, 1992 and 1997, possibly reflecting the role of temporal variation as a contributor to desertification. The average number of sheep per-household was found to be an important indicator of change in desertification risk, while changes in ridge crop planting area explained the distribution of the rate of change in desertification risk in 1988-1992. The results suggests that the RI was useful in expanding the understanding of spatial temporal desertification issues in Minqin County, as well as identifying a current set of agricultural activities related to desertification risk. Further, given the limited nature of consistent data and observations for the area, development of the RI also served to establish a baseline for future investigations into desertification change and the risks such change might pose for the region. 相似文献
267.
Calvo-Iglesias MS Fra-Paleo U Crecente-Maseda R Díaz-Varela RA 《Environmental management》2006,38(6):921-933
The aim of this work is the analysis of the dynamics in cultural landscapes, focused on the spatial distribution of changes
in land cover and landscape patterns, and their possible linkages. These dynamics have been analyzed for the years 1957 and
2000 in a sector of the north of Galicia (NW Spain) characterized with diverse landscapes. Afforestation processes linked
to agriculture abandonment and forestry specialization were the main processes observed in the study area, with the exception
of the southern mountainous sector that was dominated by ploughing of scrubland for conversion into grassland, reflecting
a specialization in livestock production. The structural changes that have taken place in most of the study area were related
to the heterogeneity aspects, although the mountainous sectors were characterized by changes in heterogeneity and fragmentation.
According to the tests performed, the comparison of the spatial distribution of both dynamics showed a certain statistical
significance, reflecting the interrelationship between patterns and processes. This approach could be useful for the identification
of areas with similar characteristics in terms of spatial dynamics so as to define more effective and targeted landscape planning
and management strategies. 相似文献
268.
The EU Water Framework Directive (WFD) requires member states to take measures to ensure that bodies of water will be in good chemical and ecological condition by 2015. Important measures to achieve this goal include reducing emissions of nitrogen (N) and phosphate (P2O5) from manure and mineral fertilizers into the environment. In regions with a high livestock density, this measure is expected to affect agricultural production and income. To quantify these effects, an environmental economic model is required that can assess alternatives capable of reducing N and P2O5 potential emissions to water. In this paper, we develop a model that is capable of analysing changes in potential emissions to water of N and P2O5 and apply it to the Netherlands, a country with large nutrient emissions. Compared to a 2015 reference scenario based on current efforts to reduce nutrient emissions, we found that the WFD measures will increase regional transport and export of manure and reduce the number of animals in the Netherlands. Fodder adjustments (defined as lower N and P2O5 input in purchased fodder) to decrease nutrient excretion in manure were a less attractive option than amongst others export, transportation of manure to another region, land use changes or reduction of the number of livestock. Compared to the reference scenario in 2015, total agricultural income will decrease by about €81.5 million per year (about €49/ha per year), although the effects will differ among parts of the Netherlands and agricultural sectors. The average predicted decrease in N emissions from agricultural sites, vulnerable to leaching into bodies of water will be almost 20% or approximately 14.7 kg N/ha per year. The reduction in N emissions to air from animal sheds, manure storage systems, application of animal manure and mineral fertilisers to the crops and grazing animals equals 6.5% or 5 kg ammonia (NH3) per hectare. 相似文献
269.
Quantification of the Impact of Land-Use Changes on Ecosystem Services: A Case Study in Pingbian County, China 总被引:3,自引:0,他引:3
Li RQ Dong M Cui JY Zhang LL Cui QG He WM 《Environmental monitoring and assessment》2007,128(1-3):503-510
Pingbian Miao Autonomous County is one of the poorest rural areas in China. Land-use changes, mainly driven by agricultural
expansion and deforestation, may significantly impact ecosystem services and functions, but such effects are difficult to
quantify. In the present study, Landsat image data were combined with the published coefficients about the world and China
ecosystem to quantify land-use and ecosystem service changes in the mountainous area. A sensitivity analysis was employed
to determine the effect of manipulating these coefficients on the estimated values. Our results show that during the past
decades (from 1973 to 2004) forests and grasslands were converted into shrubland and cropland, respectively, resulting in
a continuous decrease in ecosystem service (from 124.5 US$ × 106 in 1973 to 100.4 US$ × 106 in 2004). We found that the decrease of mixed forest in the study area was the largest contributor (i.e., 25.4 US$ × 106) to the decline of the ecosystem service. Therefore we propose that future land-use policy should pay more attention to the
crucial ecosystem functions of these forests (including tropical forest), and that it is necessary to balance the relationship
between the livelihood of local farmers and environmental protection in order to maintain a healthy and stable ecosystem. 相似文献
270.
Water resources and land use are closely linked with each other and with regional climate, assembling a very complex system. The understanding of the interconnecting relations involved in this system is an essential step for elaborating public policies that can effectively lead to the sustainable use of water resources. In this study, an integrated modelling framework was assembled in order to investigate potential impacts of agricultural expansion and climate changes on Irrigation Water Requirements (IWR) in the Taita Hills, Kenya. The framework comprised a land use change simulation model, a reference evapotranspiration model and synthetic precipitation datasets generated through a Monte Carlo simulation. In order to generate plausible climate change scenarios, outputs from General Climate Models were used as reference to perturbing the Monte Carlo simulations. The results indicate that throughout the next 20 years the low availability of arable lands in the hills will drive agricultural expansion to areas with higher IWR in the foothills. If current trends persist, agricultural areas will occupy roughly 60% of the study area by 2030. This expansion will increase by approximately 40% the annual water volume necessary for irrigation. Climate change may slightly decrease crops' IWR in April and November by 2030, while in May a small increase will likely be observed. The integrated assessment of these environmental changes allowed a clear identification of priority regions for land use allocation policies and water resources management. 相似文献