This study finds out seasonal and monthly variations in Aerosol Optical Depth (AOD) over eastern and western routes of China Pakistan Economic Corridor (CPEC) and the relationship between AOD and meteorological parameters (i.e., temperature, rainfall and wind speed). The Moderate Resolution Imaging Spectroradiometer (MODIS) and Multi-angle Imaging Spectroradiometer (MISR) data was used from the terra satellite for the period of 2000-2016. This study aims to overtake the conventional view of the purpose of using the satellite datasets. This study takes on to the concept that validated satellite data sets rather should be used for the analysis instead of just validation specifically for our study region. Hence, after comparing MODIS AOD with MISR AOD, only MISR AOD dataset is used for further analysis. The results show a decreasing trend of AOD in summer season, a positive relationship between temperature and AOD during winter and spring seasons whereas a positive relationship between wind speed and AOD in winter and spring seasons over eastern and western routes. Periodic analysis of MODIS AOD and MISR AOD depicts May-Aug as the peak period of aerosol concentration over central Pakistan. The inter-annual analysis shows the aerosol trend remained higher during summer season however rainfall shows the washout effect. Eastern route has higher standard deviation and larger values for aerosol prevalence as compared to western route. The trajectory analysis using the HYSPLIT model suggests the bias of air mass trajectory caused deviation in the aerosol trend in the year 2014. 相似文献
Abstract: In central Africa, where governments and funding agencies cover only a fraction of the recurrent expenditures needed to effectively manage the protected-areas network, it is essential to invest in the people who will be called on to participate in conservation efforts over the long term. In the Gamba Protected Areas Complex in southwestern Gabon, we analyzed the perseverance of all those who participated in training sessions, held since 1996, in ecological survey techniques and in participatory rural appraisal (socioeconomic studies). Of government agents who attended the respective training sessions, 7.7% continued ecological surveys and 0% continued participatory rural appraisal 2 years after training. However, 76.2% and 60.0% of the members of local communities who received training were still active in ecological surveys and participatory rural appraisal respectively after 2 years. Definitive conclusions regarding the participation of nongovernmental organization members cannot be drawn because of the low number of initial participants in the training programs. Based on our results, village collaborators seem to be a more "sustainable" human resource than government agents or of nongovernmental organizations members. Even though local communities cannot be solely responsible for managing protected areas, today's conservation professionals must acknowledge the strengths and limitations of village collaborators. Implementing a process involving the participation and the emulation of community members is a demanding task because protected-area managers must be based in the field to identify key individuals and to organize intensive training sessions. Also, constant support must be provided during the first years, and then the most capable and motivated collaborators will be able to pursue further training and work their way up through the ranks of the protected area's organizational structure. 相似文献
Adult sockeye salmon (Oncorhynchus nerka, N = 179) from six Fraser River populations (British Columbia) were intercepted in continental shelf waters ∼215 km from the
Fraser River mouth, gastrically implanted with acoustic transmitters, non-lethally biopsied for blood biochemistry, gill Na+,K+-ATPase activity and somatic energy density and then released. Migration behaviour and travel times to the river mouth and
into the river were monitored by underwater telemetry receivers positioned at the river mouth and in the river. Post-release
survival of salmon was excellent, with 84% (N = 150) of fish reaching the furthest receiving station ∼85 km upriver. Fish from Late-summer run populations (Adams and Weaver
Creek) averaged a migration rate of ∼20 km day−1 through the marine area and held at the river mouth and adjacent areas for 7–9 days before entering the river. Summer-run
populations (Birkenhead, Chilko, Horsefly and Stellako) had a migration rate ∼33 km day−1 and held for only 1–3 days. Once in river, similar patterns were observed: Late-run populations migrated at ∼28 km day−1 and Summer-run populations at ∼40 km day−1. From point of release to the river mouth, males migrated faster than females, but once in river migration rates did not
differ between sexes. Among all females, a correlation was discovered between levels of circulating testosterone and river
entry timing. This correlation was not observed among males. Plasma K+, Cl−, glucose, lactate and osmolality were also correlated with entry timing in both sexes. 相似文献
Environmental Chemistry Letters - With the increasing focus on renewable materials and sustainability issues, the development of non-conventional materials from natural resources and possessing... 相似文献
New approaches to forest planning are needed to support the transition of European forests to sustainable management. The aim of this study is to review forest planning systems already in place throughout Europe by exploring a set of case-study countries reflecting the main silvicultural schools of Western Europe, including Belgium, Finland, France, Italy, Portugal, and Slovenia.
A literature review and case-study data were used to assess the scale factors (vertical logic) as well as the relationships between forest planning and other environmental/land-use planning sectors (horizontal logic). The influence of EU policy on the development of forest planning is also discussed. As assessed using the vertical logic, the multi-scale and multi-topic planning approaches adopted in the countries studied here are highly heterogeneous. The horizontal logic shows that despite the importance of an inter-sectoral and harmonic relational framework between forest planning and the planning efforts of other sectors such as landscape and urban planning, the various plans are barely consistent with each other across the European countries studied here. Although interest is growing in the multi-functionality of forests, their sustainable management calls for the development of better integrated planning approaches across Europe. 相似文献
The knowledge of acid-base characteristics of humic acid (HA) and fulvic acid (FA) fractions of organic amendments and amended soils is of considerable importance for assessing their agronomic efficacy and environmental impact. In this work, the acid-base properties of HAs and FAs isolated from pig slurry, soils amended with either 90 or 150 m(3) ha(-1) yr(-1) of pig slurry for 3 yr, and the corresponding nonamended control soil were investigated by using a current potentiometric titration method. The nonideal competitive adsorption (NICA) model that describes proton binding by two classes of binding sites (carboxylic- and phenolic-type groups) was successfully fit to titration data. With respect to the control soil HA and FA, pig-slurry HA and FA were generally characterized by smaller carboxylic-type group contents, slightly smaller phenolic-type group contents, larger affinities for proton binding by the carboxylic-type groups, and much smaller, in the case of the HA fraction, or similar, in the case of the FA fraction, affinities for proton binding by the phenolic-type groups. Amendment with pig slurry determined a number of modifications in soil HAs and FAs, including decrease of acidic functional group contents, and slight increase of the proton affinity of the carboxylic-type groups. Further, a slight decrease of the affinities for proton binding by the phenolic-type groups of HAs was observed. These effects can have a large impact on the biological availability, mobilization, and transport of macro- and micronutrients, toxic metal ions, and xenobiotic organic cations in pig slurry-amended soils. 相似文献