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861.
862.
Anna Leung Zong Wei Cai Ming Hung Wong 《Journal of Material Cycles and Waste Management》2009,11(3):173-173
Special FeatureWaste Management Research in Korea
A new joint publication 相似文献863.
Li Li Shixiao Yu Baoping Ren Ming Li Ruidong Wu Yongcheng Long 《Environmental science and pollution research international》2009,16(4):474-478
Background, aim, and scope The Yunnan snub-nosed monkey is one of the most endangered primates in the world. It is experiencing a range of ongoing threats
and the persisting effects of past disturbances. The prospects for this species are not very optimistic because habitat corridors
are severely damaged by logging, grazing, and mining. Each group of the monkeys in different areas is facing a unique variety
of threats. Based on genetic analysis, Rhinopithecus bieti should be separated into three management units for conservation, of which the Mt. Laojun management unit involves the most
endangered primates. Despite the fact that the vegetation on Mt. Laojun is in a relatively pristine state, only two groups
of monkeys, of a total of fewer than 300, survive in the area. With this paper, we aimed to address the capacity of the monkeys’
habitat at the study site and the possible reasons for the small populations.
Materials and methods Rapid ecological assessment based on a SPOT 5 image and field survey was used to simulate the vegetation of the whole area
based on reference ecological factors of the GIS system. The vegetation map of the site was thus derived from this simulation.
Based on the previous studies, the three vegetation types were identified as the suitable habitat of the monkeys. The confusion
matrix-based field GPS points were applied to analyze the precision of the habitat map. Based on the map of suitable habitat
of the monkeys, the utilization of the habitat and the carrying capacity were analyzed in the GIS.
Results The confusion matrix-based field GPS points were applied to the habitat analysis process, and it was found that the habitat
map was 81.3% precise. Then, with the current habitat map, we found that the mixed forest currently used by the monkeys is
only a very small fraction (2.65%) of the overall potential habitat of the population, while the dark conifer forest is 4.09%.
Discussion Poaching is the greatest short-term threat to this species, particularly in the southern range where local residents have
a strong tradition of hunting. Quite a few individual monkeys are still trapped accidentally due to the high density of traps.
These problems are hard to mitigate because it is difficult to enforce laws due to the extremely rugged terrain.
Conclusions The results show that there is a great ecological capacity of the area for the monkey’s survival and a great potential for
an expansion of the monkey population at the site. Based on the current population and its geographical range, it can be estimated
that the suitable habitat area defined by this study can support more monkeys, about many times the current population. Thus,
at least in the Mt. Laojun Area, poaching pressure is the main factor to be responsible for the low density of Yunnan snub-nosed
monkeys instead of habitat alteration.
Recommendations and perspectives Based on these results, some suggestions relating to conservation can be made: Focus conservation efforts on the current distribution
area of the monkeys and create a 20 km buffer zone; design a long-term plan for the suitable habitat outside the buffer zone
to set up a wildlife corridor in the long run; establish an association for the local hunters exploiting, their knowledge
on the animals to promote monkey conservation and stop poaching. Also, the map derived from the study helps managers to allocate
conservation resources more efficiently and enhances the overall outcomes of conservation measures. 相似文献
864.
在相同接种配比(接种污泥占餐厨垃圾的质量分数为30%)条件下,研究了4种不同来源污泥(压滤污泥、厌氧污泥、曝气污泥和河底淤泥)添加或不添加缓冲剂时对餐厨垃圾厌氧发酵产氢效果的影响.结果发现,在不添加缓冲剂时.4种污泥接种餐厨垃圾厌氧发酵平均产氢量依次为厌氧污泥>河底淤泥>压滤污泥>曝气污泥,接种厌氧污泥的餐厨垃圾平均产氢量最高,达10.11mL(以每克挥发性固体(VS)计,下同);而添加缓冲剂时.4种污泥接种餐厨垃圾厌氧发酵平均产氢量依次为厌氧污泥>曝气污泥>压滤污泥>河底淤泥,接种厌氧污泥的餐厨垃圾平均产氢量也最高,为33.72 mL,且体系pH得以缓冲. 相似文献
865.
由于三元复合驱原油中新型驱油用化学品的应用以及原油劣质化使得采出水乳化严重.而且三元复合驱采出水经油水分离后含油量升高.基于此.通过对不同类型的破乳剂的分析及其工艺条件的考察,探讨了影响三元复合驱采出水破乳的因素,其中破乳剂FB94具有较好的破乳效果.采用模拟三元复合驱采出水(碱为1 200 mg/L、聚合物为200 mg/L、表面活性剂为400mg/L),投加破乳剂FB94为160 mg/L,控制沉降时问为120 min、温度为45℃,当初始含油量为5 000 mg/L时.破乳后水中含油量降至195 mg/L,脱油率为96.1%,当初始含油量为1 500 mg/L时,破乳后水中含油量降至87 mg/L.脱油率为94.2%. 相似文献
866.
不同污泥浓度对生物沥滤过程的影响 总被引:2,自引:1,他引:1
以硫酸亚铁盐作为底物,氧化亚铁硫杆菌(Thiobacillus ferrooxidans)为主要沥滤微生物,在底物投配比为10 g/L,温度为25℃,曝气量为1 L/min的条件下,对5种不同浓度的桂林城市污泥中重金属进行生物沥滤试验。结果表明,生物沥滤的污泥浓度宜控制在25.6 g/L,沥滤3 d后,污泥中超标元素Cu、Zn和Cd的去除率分别达到58.17%、75.90%和93.64%,沥滤处理后污泥中残余重金属含量符合污泥农用的国家标准。 相似文献
867.
渤南低渗透油田污水生化处理室内模拟研究 总被引:1,自引:0,他引:1
渤南油田属典型的低渗透油田,注水水质要求达到A1级,而污水中的分散油和乳化油是污水处理的难点和重点。为给污水站的建设提供合适的污水处理工艺单元和最佳参数,通过室内模拟研究,采用生物接触氧化技术处理油田污水。结果表明,当污水停留时间为8 h时,生化系统可将污水含油量由10~25 mg/L降低到1 mg/L以下,去除率高达96.18%,COD稳定在100 mg/L以内,通过生物之间的竞争作用和高浓度的氧,有效地抑制了硫酸盐还原菌的生长,使腐蚀率控制在0.076 mm/a以下。同时,该试验表明,8 h为生物接触氧化处理工艺的最佳停留时间。 相似文献
868.
869.
Life cycle assessment is applied to assess the ultraclean micronized coal oil water slurry (UCMCOWS) with SimaPro and the environmental impact of UCMCOWS on its whole life cycle is also analyzed. The result shows that the consumption of energy and products are increasing along with the deepening of UCMCOWS processing, UCMCOWS making and combustion are the two periods which have a bigger impact on eco-system and human health. As a new substitute of fuel, UCMCOWS merits to be utilized more efficiently and reasonably. 相似文献
870.
Changsub Shim Qinbin Li Ming Luo Susan Kulawik Helen Worden John Worden Annmarie Eldering Glenn Diskin Glen Sachse Andy Weinheimer David Knapp Deedee Montzca Teresa Campos 《Atmospheric environment (Oxford, England : 1994)》2009,43(8):1540-1547
Concurrent tropospheric O3 and CO vertical profiles from the Tropospheric Emission Spectrometer (TES) during the MILAGRO/INTEX-B aircraft campaigns over the Mexico City Metropolitan Area (MCMA) and its surrounding regions were used to examine Mexico City pollution outflow on a regional scale. The pollution outflow from the MCMA occurred predominantly at 600–800 hPa as evident in O3, CO, and NOx enhancements in the in situ aircraft observations. TES O3 and CO are sensitive to the MCMA pollution outflow due to their relatively high sensitivities at 600–800 hPa. We examined O3, CO, and their correlation at 600–800 hPa from TES retrievals, aircraft measurements, and GEOS-Chem model results. TES captures much of the spatial and day-to-day variability of O3 seen in the in situ data. TES CO, however, shows much less spatial and day-to-day variability compared with the in situ observations. The ΔO3/ΔCO slope is significantly higher in the TES data (0.43) than the in situ data (0.28) due partly to the lack of variability in TES CO. Extraordinarily high ΔO3/ΔCO slope (0.81) from TES observations at 618 hPa over the Eastern U.S. was previously reported by Zhang et al. [Zhang, L., Jacob, D.J., Bowman, K.W., et al., 2006. Ozone–CO correlations determined by the TES satellite instrument in continental outflow regions. Geophys. Res. Lett. 33, L18804. 10.1029/2006GL026399.]. Thus the application of TES CO–O3 correlation to map continental pollution outflow needs further examination. 相似文献