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171.
172.
I. V. Emelyanova G. E. Donald D. J. Miron D. A. Henry M. G. Garner 《Environmental Modeling and Assessment》2009,14(4):449-465
A probabilistic Bayesian method called weights of evidence (WofE) was used to develop a synthetic dataset of cattle farm locations at a national scale across Australia. The synthetic
dataset was required for the modelling of livestock movements with a view to assessing biosecurity implications. The WofE method is based on the analysis of spatial relationships between evidential patterns with respect to an event, such
as the actual location of a farm. The evidential patterns of cattle farms were derived from maps of land use, land tenure,
drainage systems, roads, settlements and long-term averaged rainfall. These evidential patterns were used for delineating
and ranking land areas suitable for cattle farming. For each evidential pattern statistics such as a positive weight, a negative weight and a contrast were calculated for estimating the degree of correlation between the evidential patterns and known farm locations. The integrated
evidential patterns of known farms were then used for estimating posterior probabilities and splitting land into five different
classes according to its suitability for farming.
相似文献
I. V. EmelyanovaEmail: |
173.
功能区噪声自动监测点位布设探讨 总被引:1,自引:0,他引:1
分析了各类功能区噪声的特点,提出自动监测点位布设的基本原则。对传声器水平距离和垂直高度的确定做了相关比对实验,结果表明,传声器水平距离选择距反射面不小于3 m,垂直高度为4~5m时,能较好地反映该功能区受环境噪声影响状况。 相似文献
174.
175.
Drouet JL Capian N Fiorelli JL Blanfort V Capitaine M Duretz S Gabrielle B Martin R Lardy R Cellier P Soussana JF 《Environmental pollution (Barking, Essex : 1987)》2011,159(11):3156-3161
Modelling complex systems such as farms often requires quantification of a large number of input factors. Sensitivity analyses are useful to reduce the number of input factors that are required to be measured or estimated accurately. Three methods of sensitivity analysis (the Morris method, the rank regression and correlation method and the Extended Fourier Amplitude Sensitivity Test method) were compared in the case of the CERES-EGC model applied to crops of a dairy farm. The qualitative Morris method provided a screening of the input factors. The two other quantitative methods were used to investigate more thoroughly the effects of input factors on output variables. Despite differences in terms of concepts and assumptions, the three methods provided similar results. Among the 44 factors under study, N2O emissions were mainly sensitive to the fraction of N2O emitted during denitrification, the maximum rate of nitrification, the soil bulk density and the cropland area. 相似文献
176.
利用新湖农场1998—2007年气象、社会、经济资料及实测植被、土壤数据,分析了近10年来防沙治沙情况,并选取定量、定性指标,建立效益评估模型,对植物治沙产生效益进行评估。结果表明:植被覆盖率由1990年1.63%提高到2007年5.37%,植物种类、土壤碱解N、速效P随栽植年限增加而上升,沙化面积比例由1990年的2.90%减少到2006年的0.59%,风沙天气由1998年的27次减少到2007年的4次;农场土地利用结构得到优化,人均林草面积由1990年人均0.02hm2增加到2006年0.15hm2。 相似文献
177.
178.
Kathleen F. Carlson Author Vitae Susan G. Gerberich Author Vitae Author Vitae Ann S. Masten Author Vitae Author Vitae John M. Shutske Author Vitae Author Vitae Colleen M. Renier Author Vitae 《Journal of Safety Research》2009,40(2):97-103
Problem
Children on family agricultural operations have high risk of injury. The association between children's behavioral traits and their risk of injury is not well understood.Method
Data from the Regional Rural Injury Study-II were used to assess behavioral risk factors for injury to children ages six to < 20 years. A total of 379 injury events (cases) and 1,562 randomly selected controls were identified. Adjusted odds ratios (OR) and 95% confidence intervals (CI), calculated using logistic regression, were used to estimate injury risk in reference to behavioral traits.Results
Injury risks were greater for children with high levels of depressive symptoms (OR = 1.9, CI = 1.0-3.7) and aggression (OR = 1.6, CI = 0.9-2.7), and low levels of careful/cautious behavior (OR = 1.8, CI = 1.1-2.9). Children with low levels of self-regulation had reduced risks (OR = 0.4, CI = 0.2-0.8).Discussion
Results suggest that children's behaviors affect their risk of agricultural injury. Additional research could elucidate mechanisms and inform interventions.Impact on industry
The development of multifaceted, sustainable approaches for prevention is necessary for this unique population. These findings suggest a need for interventions that incorporate specific behavior-related risk factors in the context of family farms and ranches. 相似文献179.
F. R. Funes-Monzote Marta Monzote E. A. Lantinga H. van Keulen 《Environment, Development and Sustainability》2009,11(4):765-783
From the 1960s onwards, a ‘High External Input’ dairy production model was applied widely in Cuba. Overall milk production
of the national herd increased considerably, but the system was inefficient from both a financial and energetic point of view.
In the early 1990s, after the abrupt end of inflow of capital and other resources from Eastern Europe, the dairy sector collapsed.
In the short term, the modern infrastructure of milk production deteriorated and the sector experienced profound vulnerability.
However, in the longer term, this situation stimulated a search for more sustainable approaches, such as low external input
Mixed Farming Systems (MFS). The current study aimed to evaluate two small scale prototype farms to assess the implications
of converting ‘Low External Input’ Dairy Farming Systems into MFS. Fifteen agro-ecological and financial indicators were selected
and monitored over a 6-year period. Two configurations of MFS, i.e. the proportion of the farm area occupied by arable crops,
were tested: 25 and 50%. Productivity, energy efficiency and cost-effectiveness all improved following conversion. Total energy
input was low for both farms and decreased over time, whereas energy efficiency was high and increased over time. Human labour
input was high directly following conversion, but decreased by one-third over the 6-year period. This study demonstrates,
at an experimental scale, the potential of MFS to achieve ecological, productivity and financial advantages for dairy production
in Cuba.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
180.
Geoffrey R. Squire Cathy Hawes Graham S. Begg Mark W. Young 《Environmental science and pollution research international》2009,16(1):85-94