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891.
海南省麒麟菜自然保护区麒麟菜资源研究 总被引:2,自引:0,他引:2
2012年对海南省麒麟菜保护区内野生麒麟菜资源进行调查研究。结果表明,海南省麒麟菜自然保护区有琼枝和耳突卡帕藻2种麒麟菜,优势种为琼枝。保护区内麒麟菜分布面积约为19.40 km2,平均覆盖度为0.54%,平均生物量为7.30 g/m2。其中文昌海域约为14.35 km2,平均覆盖度为0.55%,平均生物量为7.85 g/m2;琼海海域约为5.05 km2,平均覆盖度为0.49%,平均生物量为5.78 g/m2。伴生生物有33科50种,其中多毛类有9科14种,软体动物有14科17种,甲壳类9科18种以及棘皮动物1科1种,平均生物量为6.38 g/m2,平均栖息密度为72.72个/m2。优势种为斑纹围沙蚕、地中海巨亮钩虾、雷氏藻钩虾和四肢舟钩虾。受草食性动物、渔业活动、陆源污染和海洋工程影响海南省麒麟菜保护区麒麟菜大面积减少。 相似文献
892.
Provenances of atmospheric dust over Korea from Sr–Nd isotopes and rare earth elements in early 2006
Min Kyung Lee Yong Il Lee Hi-Il Yi 《Atmospheric environment (Oxford, England : 1994)》2010,44(20):2401-2414
Sr and Nd isotopic composition of pre- and syn-Asian dust (Hwangsa) particles collected from three different water depths at two different offshore sites, western Korea and rare earth elemental composition of syn-Asian dust particles collected from three islands around the Korean Peninsula in late April 2006 were analyzed to interpret their provenance. The dust Sr–Nd isotopic compositions vary spatiotemporally, but they show specific values when the Hwangsa event occurred. Satellite images, airmass backward trajectory modeling, and comparison with Sr–Nd isotopic ratios and rare earth elements compositions of soils and desert sands of northern China all suggest the major source of dust particles for the late April 2006 Hwangsa event to be the Mu Us Desert in northern China. Dust particles of the pre-Hwangsa period include both background dusts and the previous Hwangsa event dust particles, and they are interpreted to have been originated from various arid regions of China such as the Hobq Desert, the Mu Us Desert, and the Taklamakan Desert in different times. Different background dust sources during pre-Hwangsa period in early 2006 resulted from the changing route of the westerlies. 相似文献
893.
电力安全工器具种类多、数量大,作为保障各类电工操作安全、有序作业必不可少的器具,高效率、专业化和智能型管理是电力企业安全质效提升的重要举措。针对现场电力安全工器具管理存在的诸多问题,基于“云平台”自动模式识别技术,研发电力安全工器具智能管理系统,集各个安全工器具身份标识、位置信息、出入库记录、损坏报废标记以及超过检测周期警报提示为一体。通过周期测试和现场应用,结果表明:该系统以安全工器具个体为管理单元,分层分类,构建大数据库,信息覆盖全面完整;分布式区块链技术有力支撑平台数据的实时更新和资源共享,提升管理效率;指纹登录,智能感应,出入库时间缩短了2/3,取用便捷,提高工作效率;智能扫描检测功能,及时警示反馈,有效避免现场违规使用事件的发生,助力安全生产,夯实安全质效。 相似文献
894.
Liu Jinfeng Yuan Dong Lu Ming You Yong Zhang Guangze Feng Tao Wang Dong Lin Zhiheng 《Environmental Fluid Mechanics》2021,21(6):1253-1271
Environmental Fluid Mechanics - Experimental tests were conducted on a rectangular flume with different grid-type dam grid sizes, channel slopes and debris flow bulk density. We use the Bernoulli... 相似文献
895.
Effects of sandy desertified land rehabilitation on soil carbon sequestration and aggregation in an arid region in China 总被引:1,自引:0,他引:1
Yong Zhong Su Xue Fen Wang Rong Yang Jaehoon Lee 《Journal of environmental management》2010,91(11):2109-2116
The rehabilitation of sandy desertified land in semi-arid and arid regions has a great potential to increase carbon sequestration and improve soil quality. Our objective was to investigate the changes in the soil carbon pool and soil properties of surface soil (0–15 cm) under different types of rehabilitation management. Our study was done in the short-term (7 years) and long-term (32 years) desertification control sites in a marginal oasis of northwest China. The different management treatments were: (1) untreated shifting sand land as control; (2) sand-fixing shrubs with straw checkerboards; (3) poplar (Populus gansuensis) shelter forest; and (4) irrigated cropland after leveling sand dune. The results showed that the rehabilitation of severe sandy desertified land resulted in significant increases in soil organic C (SOC), inorganic C, and total N concentrations, as well as enhanced soil aggregation. Over a 7-year period of revegetation and cultivation, SOC concentration in the recovered shrub land, forest land and irrigated cropland increased by 4.1, 14.6 and 11.9 times compared to the control site (shifting sand land), and increased by 11.2, 17.0 and 23.0 times over the 32-year recovery period. Total N, labile C (KMnO4–oxidation C), C management index (CMI) and inorganic C (CaCO3–C) showed a similar increasing trend as SOC. The increased soil C and N was positively related to the accumulation of fine particle fractions. The accumulation of silt and clay, soil C and CaCO3 enhanced the formation of aggregates, which was beneficial to mitigate wind erosion. The percentage of >0.25 mm dry aggregates increased from 18.0% in the control site to 20.0–87.2% in the recovery sites, and the mean weight diameter (MWD) of water-stable aggregates significantly increased, with a range of 0.09–0.30 mm at the recovery sites. Long-term irrigation and fertilization led to a greater soil C and N accumulation in cropland than in shrub and forest lands. The amount of soil C sequestration reached up to 1.8–9.4 and 7.5–17.3 Mg ha?1 at the 0–15 cm layer over a 7- and 32-year rehabilitation period compared to the control site, suggesting that desertification control has a great potential for sequestering soil C and improving soil quality in northwest China. 相似文献
896.
Yong Geng Zuoxi Liu Bing Xue Huijuan Dong Tsuyoshi Fujita Anthony Chiu 《Environmental science and pollution research international》2014,21(23):13572-13587
Industrial symbiosis is the sharing of services, utility, and by-product resources among industries. This is usually made in order to add value, reduce costs, and improve the environment, and therefore has been taken as an effective approach for developing an eco-industrial park, improving resource efficiency, and reducing pollutant emission. Most conventional evaluation approaches ignored the contribution of natural ecosystem to the development of industrial symbiosis and cannot reveal the interrelations between economic development and environmental protection, leading to a need of an innovative evaluation method. Under such a circumstance, we present an emergy analysis-based evaluation method by employing a case study at Shenyang Economic and Technological Development Zone (SETDZ). Specific emergy indicators on industrial symbiosis, including emergy savings and emdollar value of total emergy savings, were developed so that the holistic picture of industrial symbiosis can be presented. Research results show that nonrenewable inputs, imported resource inputs, and associated services could be saved by 89.3, 32.51, and 15.7 %, and the ratio of emergy savings to emergy of the total energy used would be about 25.58 %, and the ratio of the emdollar value of total emergy savings to the total gross regional product (GRP) of SETDZ would be 34.38 % through the implementation of industrial symbiosis. In general, research results indicate that industrial symbiosis could effectively reduce material and energy consumption and improve the overall eco-efficiency. Such a method can provide policy insights to industrial park managers so that they can raise appropriate strategies on developing eco-industrial parks. Useful strategies include identifying more potential industrial symbiosis opportunities, optimizing energy structure, increasing industrial efficiency, recovering local ecosystems, and improving public and industrial awareness of eco-industrial park policies. 相似文献
897.
Henglong Xu Wei Zhang Yong Jiang 《Environmental science and pollution research international》2014,21(11):7097-7112
The feasibility for developing a protocol to assess marine water quality based on early colonization features of periphytic ciliate fauna was studied in coastal waters of the Yellow Sea, northern China. The ciliate communities with 3–28-day ages were collected monthly at four stations with a spatial gradient of environmental stress from August 2011 to July 2012. The spatial patterns of both early (3–7 days) and mature (>10 days) communities of the ciliates represented significant differences among the four stations, and were significantly correlated with environmental variables, especially nutrients and chemical oxygen demand (COD). Seven and eight dominant species were significantly correlated with nutrients or COD within the early and mature communities, respectively. The species richness indices were strongly correlated with nutrients, especially in mature communities. These findings suggest that it is possible to assess the status of water quality using early colonization features of periphytic ciliate fauna in coastal waters. 相似文献
899.
Shaheen Sabry M. Antoniadis Vasileios Kwon Eilhann E. Biswas Jayanta K. Wang Hailong Ok Yong Sik Rinklebe Jörg 《Environmental geochemistry and health》2018,40(1):561-562
Environmental Geochemistry and Health - Unfortunately, in the original publication of the article, Prof. Yong Sik Ok’s affiliation was incorrectly published. 相似文献
900.
J. Berton C. Harris Morgan W. Tingley Fangyuan Hua Ding Li Yong J. Marion Adeney Tien Ming Lee William Marthy Dewi M. Prawiradilaga Cagan H. Sekercioglu Suyadi Nurul Winarni David S. Wilcove 《Conservation biology》2017,31(2):394-405
The trade in wild animals involves one‐third of the world's bird species and thousands of other vertebrate species. Although a few species are imperiled as a result of the wildlife trade, the lack of field studies makes it difficult to gauge how serious a threat it is to biodiversity. We used data on changes in bird abundances across space and time and information from trapper interviews to evaluate the effects of trapping wild birds for the pet trade in Sumatra, Indonesia. To analyze changes in bird abundance over time, we used data gathered over 14 years of repeated bird surveys in a 900‐ha forest in southern Sumatra. In northern Sumatra, we surveyed birds along a gradient of trapping accessibility, from the edge of roads to 5 km into the forest interior. We interviewed 49 bird trappers in northern Sumatra to learn which species they targeted and how far they went into the forest to trap. We used prices from Sumatran bird markets as a proxy for demand and, therefore, trapping pressure. Market price was a significant predictor of species declines over time in southern Sumatra (e.g., given a market price increase of approximately $50, the log change in abundance per year decreased by 0.06 on average). This result indicates a link between the market‐based pet trade and community‐wide species declines. In northern Sumatra, price and change in abundance were not related to remoteness (distance from the nearest road). However, based on our field surveys, high‐value species were rare or absent across this region. The median maximum distance trappers went into the forest each day was 5.0 km. This suggests that trapping has depleted bird populations across our remoteness gradient. We found that less than half of Sumatra's remaining forests are >5 km from a major road. Our results suggest that trapping for the pet trade threatens birds in Sumatra. Given the popularity of pet birds across Southeast Asia, additional studies are urgently needed to determine the extent and magnitude of the threat posed by the pet trade. 相似文献