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591.
For making rational and scientific land-use planning,an inventory indicator of land productivity subject to biophysical limitations and human disturbance is required.This study introduces agricultural land productivity(ALP)as the dynamic indicator to measure land productivity,involving factors that affect agricultural production,such as characteristics of climate,soil,and terrain.As a case study of this dynamic indicator,ALP was estimated at county level and aggregated into provincial level in the whole of China.The result shows that ALP increased during 2000-2010 in China,and the ratios of ALP to the actual grain yield were 65.40%and 66.38%in the years 2000 and 2005,respectively.The ALP is an effective dynamic indicator to estimate the land productivity and to represent the basic conditions about the supply of water,energy,nutrients,and the physical basis for plant growth,as well as the local input.ALP estimation could provide supporting information for policy-making about land production planning and land-use management. 相似文献
593.
To create Safe Community is considered a new methodology to promote Harmonious Society in China. Safe Community (SC) is centralized by “injury prevention” which is a concept involved from occupational safety and health in process industry. In this paper, it first examined the definition and elements of SC. Then, it introduced a Safe Community program in Honey Lake of Futian District of Shenzhen in detail to depict the actual procedure to create a desired Safe Community in China. In this application, Occupational Safety and Health Council in Hong Kong played an important role to instruct the design and execution of SC principle and suggest ways to crystallize a culture of safety within a Chinese community. From the SC program in Honey Lake of Futian District of Shenzhen, China has found out a new way to promote injury prevention in a community. Also, using these experiences from this program, more SC could be constructed that is beneficial to the safety and health of Chinese people. 相似文献
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595.
微生物絮凝剂产生菌的絮凝性能 总被引:7,自引:0,他引:7
从废水处理厂和土壤中分离产絮凝剂的菌株,其中一株产絮凝剂的细菌W7—1对高岭土的絮凝活性达94%,初步鉴定该菌为Klebiella sp.,W7—1对产絮凝剂的培养条件要求简单,产絮凝剂的最佳碳源和氮源为蔗糖和牛肉膏,pH在5~10的范围内都适应絮凝剂的产生,但pH为8.0时絮凝活性最高。絮凝剂的添加量为10mL/L、絮凝体系pH为7~10时絮凝活性好,提纯后的絮凝剂产量高于其它絮凝剂近10倍,分析表明,絮凝剂成分为多糖,且有很好的热稳定性,加热至100℃、30min后絮凝活性不变。 相似文献
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598.
Xing-Ming Hao Yang Li Hai-Jun Deng 《Environmental monitoring and assessment》2013,185(12):10027-10038
The roots of Populus euphratica, a plant that grows in the lower reaches of the Tarim River, Northwest China, exhibit a significant level of hydraulic redistribution; however, quantitative assessments of the water-sharing process and its ecological effects are limited. This study was designed to obtain such data using an assessment model based on field observation parameters, including soil water content (soil water potential), root distribution, and stable isotope δ18O values of soil and plant samples during the entire growing season. The results showed that hydraulic redistribution in P. euphratica can be detected in 0–120 cm soil layers, with the amount of hydraulically redistributed water (HRW) in the soil found at different depths as follows: 60–80?>?40–60?>?20–40?>?0–20?>?80–100?>?100–120 cm. The variations in HRW in soil layers can be partly attributed to the vertical distribution of roots. The denser roots found at greater depths positively influenced the amount of redistributed water in lower soil layers. During the growing season, the amount of HRW reached a daily average of 0.27 mm, which allowed increased transpiration and provided an adequate water supply to herbs. Based on the stable isotope (δ18O) data, the amount of HRW provided by the roots of P. euphratica could meet 22–41 % of its water demand. 相似文献
599.
Tao Hu-Chun Li Shuo Zhang Li-Juan Chen Yi-Zhen Deng Li-Ping 《Environmental geochemistry and health》2019,41(1):297-308
Environmental Geochemistry and Health - Using sodium alginate hydrogel as skeleton, in combination with chitosan and magnetic Fe3O4, a new type of magnetic chitosan/sodium alginate gel bead (MCSB)... 相似文献
600.
Qinghe Zhao Shiliang Liu Li Deng Shikui Dong Cong Wang 《Environmental monitoring and assessment》2013,185(7):6101-6110
In this study, the longitudinal distribution of heavy metals (including As, Cd, Cr, Cu, Ni, Pb, and Zn) from sediment of a 70-km long canyon reservoir in Yunnan Province was investigated and their potential ecological risks were assessed. The results indicated that the concentration of all the detected metals in the sediments that was sampled near the dam was much higher than that sampled from upstream far from the dam. The geoaccumulation index (I geo) and contamination factors (CF) suggested that Cd was the most important contamination factor, followed by As and Zn, while the concentration of Cr, Cu, Ni, and Pb was at uncontaminated levels. Cd posed a high potential ecological risk in the sediment. Furthermore, potential ecological risk is significantly correlated with the distance from the dam. 相似文献