No abstract

No abstract

No abstract

China has made efforts to protect wild yak (Bos mutus) species and prevent the hybrids between wild yak and domestic yak (Bos grunniens) species. At present, wild yak population of a reasonable estimate would be over 70,000. Due to conservation efforts in environmental protection and ecological construction such as the Wildlife Protection and Nature Reserve Construction Project, the "Grain-for-Green" Project and the Natural Forest Resources Protection Project, the number of wild yaks is increasing. In general, Tibetan Plateau's ecosystem is getting better and its environmental quality shows a gradual improving trend. Tibetan Plateau is one of the world's cleanest regions called as the "Third Pole". In order to preserve the genetic pool of wild yaks, local pastoralists and polices drive off the wild male yaks from the domestic yak herds by making noise (banging washbasins, pots, etc.) or driving cars. Local government also incentivizes the culling of domestic yaks found in wild herds. For the sake of the biological and genetic features of this wild species, and the pastoralist way of life, wild yaks should continuously be protected to keep their genetic integrity. We appeal plans to investigate the gene pollution of wild yaks in some important distribution regions of this species. In the face of hybridizing with domestic yaks, proper guidance is urgently needed to address genetic pollution and protect the genetic integrity of wild yaks.

Mercury (Hg) in indoor and outdoor air in the city core at various heights above ground, and in indoor and outdoor air was measured in Toronto, the largest city in Canada. For the measurements of gaseous elemental mercury (GEM), a mercury-monitoring system (Tekran Inc., Toronto, Canada) was used. In addition, mercury associated with indoor and outdoor particulate matter in the city and surrounding area was also measured. Mercury in outdoor particulate matter (as total filterable p-Hg) was determined through thermal desorption gold pre-concentration CVAFS. The analysis of mercury in indoor particulate matter (as settled dusts) followed the USEPA Method 1631E and Appendix to Method 1631. The results show:• the higher GEM concentration values in outdoor air were more concentrated in the city core; • GEM in indoor air was much higher than in outdoor air;• the GEM values increased with increasing elevation; • emissions from vehicles and ground surfaces in the city were not the major sources of GEM to the urban atmosphere; • the concentrations of total filterable p-Hg in outdoor air ranged from 20.1 to 63.0 pg m −3 and those for indoor settled dusts ranged from 0.01 to 10.0 mg kg −1 .The findings suggest that mercury used in the indoor environment serves as a source of Hg to the urban atmosphere.

No abstract

Atmospheric gaseous elemental mercury (GEM) and meteorological parameters were monitored at two sites in downtown Toronto, Canada from Oct. 2015 to Oct. 2016 using Tekran 2537A mercury vapour analyzers. The average concentration was found to be 1.78 ± 0.89 ng/m3 for Kerr Hall North (KHN) and 1.46 ± 0.54 ng/m3 for Jorgenson Hall (JOR) site. Analysis of the data reveals that sporadic events of high mercury concentration are related to local sources. Comparing this data set with that collected in 2004 revealed that the average atmospheric GEM concentration in downtown Toronto dropped from 4.5 ng/m3 to 1.78 ng/m3. Decreases in GEM were also observed over the same period in rural areas as measured by CAMNet. The decrease might be a result of policy change, as three key national and provincial environmental policies have been enacted since 2004. The data collected in Toronto suggest GEM concentration and distribution are influenced by local and regional sources, meteorological conditions, and changes in environmental policy.

Atmospheric gaseous elemental mercury (GEM) and meteorological parameters were monitored at two sites in downtown Toronto, Canada from Oct. 2015 to Oct. 2016 using Tekran 2537A mercury vapour analyzers. The average concentration was found to be 1.78 ± 0.89 ng/m3 for Kerr Hall North (KHN) and 1.46 ± 0.54 ng/m3 for Jorgenson Hall (JOR) site. Analysis of the data reveals that sporadic events of high mercury concentration are related to local sources. Comparing this data set with that collected in 2004 revealed that the average atmospheric GEM concentration in downtown Toronto dropped from 4.5 ng/m3 to 1.78 ng/m3. Decreases in GEM were also observed over the same period in rural areas as measured by CAMNet. The decrease might be a result of policy change, as three key national and provincial environmental policies have been enacted since 2004. The data collected in Toronto suggest GEM concentration and distribution are influenced by local and regional sources, meteorological conditions, and changes in environmental policy.