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The outbreaks of African Swine Fever (ASF) in China are ongoing, and the inadequate management of the pig supply chain is criticized. In the past four years, a series of preventive and control measures have been supplied national wide, while the outbreaks have not been terminated. This suggests the existing animal disease management at the district level may not be appropriate to control ASF under the current situation of the ASF outbreak in China. It is urgent to further describe real distribution areas of ASF in China. In this study, we combined four regional-scale models to predict the risk distribution of ASF in mainland China and identify risk factors related to ASF outbreaks. The results showed that the four regional-scale models were more accurate in predicting the ASF outbreaks than the nationwide scale model. The four regional-scale models identified the potential risk factors associated with ASF outbreaks, such as population density, pig density, land cover, temperature, and elevation factors. Moreover, seven clusters with high potential risk of ASF outbreaks were identified. Then, based on the results, we proposed more suitable prevention and control plans for ASF, which can assist the implementation of transport management policies within and between risk clusters. [ABSTRACT FROM AUTHOR]

Geological Storage of CO 2 has been identified by the provincial Alberta government as the major component of its strategy for reducing greenhouse gas emissions in the province. The issue of reducing atmospheric CO 2 emissions is particularly important for oil sands plants, whose emissions in 2013 were in the order of 55 Mt CO 2 eq. Unfortunately, the oil sands operations are located near the shallow edge of the Alberta basin, which is not suitable for CO 2 storage. However, CO 2 storage in deep Devonian oil and gas reservoirs located westward of the oil sands operations may constitute a solution for storing CO 2 from these operations. The volumetric CO 2 storage capacity in 1225 oil and gas reservoirs in 13 different Devonian formations in an area covering approximately 126,000 km2 was estimated using information from reserves and production databases. The CO 2 storage capacity has been calculated by reservoir type and by production stage. The aggregate CO 2 storage capacity in oil and gas reservoirs in the Devonian sedimentary succession in the study area is in the order of ∼700 Mt. However, most of the reservoirs have small storage capacity, and only 9 oil reservoirs and 10 gas reservoirs have CO 2 storage capacity greater than 5 Mt each, for a cumulative total of ∼447 Mt CO 2 . The strength of underlying aquifers was evaluated by performing material balance calculations for these 19 oil and gas reservoirs and it was found that they do not have a significant effect in reducing the CO 2 storage capacity of these reservoirs. The CO 2 storage capacity in the study area is bound to be greater if one considers the fact that, once the infrastructure, including pipelines, is built to bring CO 2 to any of these very large reservoirs, then smaller reservoirs in the same oil or gas field can be accessed with relatively minimal extra costs. The aggregate CO 2 storage capacity in the fields where the 19 very large oil and gas reservoirs are found has been considered as well, raising the CO 2 storage capacity in these fields to ∼491 Mt CO 2 . The storage capacity in oil reservoirs in the study area can be further increased by using CO 2 in enhanced oil recovery. Although 705 oil pools have been identified as being technically suitable for CO 2 -EOR, only 12 oil reservoirs have remaining oil in place greater than 60 million barrels that would economically justify implementation of CO 2 -EOR. Assuming various incremental recovery factors and net CO 2 utilization factors, the additional amount of CO 2 that may be stored in these 12 oil reservoirs varies between 31 and 412 Mt CO 2 , thus increasing the CO 2 storage capacity in these oil reservoirs. This evaluation shows that the potential CO 2 storage capacity in oil and gas reservoirs in Devonian strata west of the Athabasca oil sands area in Alberta is significant and has the potential to reduce the carbon footprint of the oil sands operations for several decades until other technological advances for reducing CO 2 emissions will come into being. [ABSTRACT FROM AUTHOR]

The Province of Alberta is the largest CO 2 emitter in Canada, with annual emissions close to 250 Mt, of which about 55 Mt CO 2 originate from oil production from oil sands. Geological storage of CO 2 has been identified as the major component of the strategy for reducing greenhouse gas emissions from oil sands operations, which are located in the Athabasca area close to the shallow eastern edge of the Alberta basin. Therefore, CO 2 storage in deep Devonian saline aquifers, located westward of the oil sands operations, may constitute a solution for storing CO 2 from these operations. A regional-scale study of the potential for storing CO 2 in deep Devonian saline aquifers in an area covering ∼126,000 km2 has been undertaken with the aim of identifying suitable sites for CO 2 storage. The Devonian sedimentary succession consists of a succession of stacked sandstone and carbonate saline aquifers separated by intervening shaly and evaporitic aquitards and aquicludes. The approach taken in the study, illustrated in this paper, comprises 11 steps, including: 1) Geological mapping of 29 Devonian formations based on information from more than 34,000 wells; 2) Hydrostratigraphic delineation of the 13 deep saline aquifers identified in this succession; 3) Determination of hydraulic continuity between various aquifers, due to depositional or erosional events; 4) Determination of formation water salinity, which ranges from less than 4000 mg/L (the limit of protected groundwater in Alberta) to close to 440,000 mg/L; 5) Determination of pressures and temperatures in these aquifers, which vary, respectively, between 1 and 30 MPa and between 12 °C and 135 °C; 6) Determination of the CO 2 phase and density at the top of each aquifer, the latter varying between < 25 kg/m3 where CO 2 is in gas phase to > 800 kg/m3 where CO 2 is in supercritical state; 7) Determination of well-scale porosity distribution in each aquifer, which varies between 1% and 40%, based on well logs in 8305 wells and core analyses in 5242 wells; 8) Determination of the areal distribution of CO 2 storage capacity in each aquifer, based on aquifer thickness and porosity, and CO 2 density; 10) Determination of the regions suitable for CO 2 storage in each aquifer based on legal and regulatory constraints and protection of hydrocarbon resources; 10) Determination of permeability distributions in each aquifer, which varies from < 1 mD to > 10 D, based on 214,194 core analyses in 5242 wells and 4318 drill stem tests in 3586 wells; and 11) Identification of target areas for CO 2 storage based on local storage capacity and permeability, both of which have to be high at the local scale. Eleven prospective areas in 10 deep saline aquifers, with a cumulative storage capacity of close to 4 Gt CO 2 , have been identified as a result of this process of evaluation, screening and selection. [ABSTRACT FROM AUTHOR]