Impacts of climate change on winter wheat water requirement in Haihe River Basin

Climate change and variability has the potential to impact crop growth by altering components of a region’s water balance. Evapotranspiration driven by higher temperatures can directly increase the demand of irrigation water, while indirectly decreasing the length of the annual crop growth period. The accompanying change in precipitation also affects the need to supply irrigation water. This study focuses on the spatial and temporal variation of historical and future irrigation water requirements of winter wheat (Triticum aestivum L.) in the Haihe River Basin, China. Irrigation water requirement is estimated using a simple water balance model. Climate change is incorporated by using predicted changes in daily precipitation and temperature. Changes in evapotranspiration and crop phenophase are then calculated for historical and future climate. Over the past 50 years, a decrease in total net irrigation water requirement (NIR) was observed mainly due to a reduction in the crop growth period length. The NIR is shown to decrease 2.8～6.9 mm with a 1-day reduction in growth period length. In the future, sowing period will come later and the heading period earlier in the year. The NIR in November, March and April is predicted to increase, especially in April. Increased NIR can result in increased water deficit, causing negative impacts on crop yield due to water stress. In the future, more attention should be paid to water resource management during the annual crop growth period of winter wheat in the Haihe River Basin.     

土体-结构界面接触对地下结构动力反应的影响

迄今为止,关于土体与结构交界面的接触效应对地下结构地震反应的影响尚未引起研究者们的重视,成果鲜有报道。本文基于接触面对法和非线性有限元波动分析方法,建立了考虑土体与结构界面接触效应的地下结构非线性地震反应分析模型和计算方法,并利用大型有限元软件ANSYS进行了求解。分析结果表明:土体与结构界面的接触效应对地下结构地震反应有明显影响,可能增大地下结构节点的峰值加速度、峰值位移和峰值应力反应;随着接触摩擦系数的增大,接触点的相对滑移逐渐减小,而接触应力的变化则无明显规律。     

Removal of rhodamine B from aqueous solution by BiPO4 hierarchical architecture

Hexahedron-like BiPO₄ microcrystals were sucessfully synthesized via a template-free hydrothermal method. The resulting samples were characterized by Xray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and UV-vis spectroscopy. The BiPO₄ samples were of pure monoclinic phase, and the initial amount of PO_3–4 during synthesis did not show obvious effect on the phase properties of the materials. The hexahedron-like BiPO₄ microcrystal had explicitly cut edges, and its thickness was about 1 μm. The photocatalytic performance of the BiPO₄ catalysts was evaluated by photodegradation of RhB under UV light irradiation with commerial Degussa P25 TiO₂ as reference. Compared with P25, the BiPO₄ catalysts displayed higher photocatalytic activity, with 98.7% of RhB degraded during 60-min experiment. Cost evaluation analysis was adopted to describe the energy consumption of the degradation process, and the results suggested the potential application of this material in the field of dye-contaminated wastewater treatment or environmental matrices remediation.     

Evaluation for sustainable land use in coastal areas: A landscape ecological prospect

Evaluation of sustainability is the core of research on sustainable land use. To a certain extent, traditional social, economic and ecological evaluation for sustainable land use can be regarded as an appraisal on the temporal scale without evaluation of spatial patterns. Landscape ecology can help to realize spatial evaluation for sustainable land use. In this paper, we construct landscape ecological indicators for evaluating sustainable coastal land use from the aspects of landscape productivity, threats and stability, to realize a synthetic temporal-spatial evaluation. These cover the five pillars of sustainable land use, i.e. productivity, security, protection, viability and acceptability. The results of applying landscape ecological evaluation to a case study in Wudi County in China show that land use sustainability is somewhat low and there are great regional differences between its 11 villages. We classified the 11 villages into 5 grades: strong sustainable land use, sustainable land use, weak sustainable land use, weak unsustainable land use, and strong unsustainable land use. Each grade has different land use characteristics and differs in the counter-measures required. But the core countermeasures in all the grades are to improve landscape productivity, to reduce human threats and to optimize landscape patterns.     

Quinone profiles of microbial communities in sediments of Haihe River�CBohai Bay as influenced by heavy metals and environmental factors

A total of 11 sediment samples were collected from the sites along Haihe River?CBohai Bay, with site 1 at the beginning of Haihe River and site 11 in Bohai Bay, about 150 km away from site 1. Quinone profiles were used for the analysis of microbial community as influenced by pollutants in water and sediments, such as heavy metals, and other environmental factors. Nineteen species of quinones were found at site 1 while only six species at sites 10 and 11. Both the diversity of quinone species (DQ) and the number of quinones were higher in the sediments from Haihe River and the near-sea area of Bohai Bay than in those from the deep-sea area. The ?? diversity values were significantly higher, while Jaccard indexes of similarity were much lower among non-contiguous pairs of sites as compared with the contiguous ones. Cluster analysis indicated that quinone profiles may be grouped into two main clusters (sites 1?C7 and sites 8?C11), and there were higher similarities within the groups than between groups. Quinone species composition varied at different sites. Ubiquinones such as UQ-8, UQ-9, and UQ-10 and menaquinones such as MK-6, MK-7, MK-8 were isolated from all the sites and accounted for the largest proportions. Pearson correlation analysis revealed that both the number of quinone species and DQ correlated positively with total organic carbon contents in water and sediments, but negatively correlated with salinity and electroconductivity and did not correlate significantly with heavy metal contents in water.     

Experimental study on the discharge characteristics of viscous debris flow with grid-type dam

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...     

Improving enterprise competitive advantage with industrial symbiosis: case study of a smeltery in China

Industrial symbiosis, a subfield of industrial ecology, focuses on transforming the waste of one firm into the valuable input of another, which improves the competitive advantages of supply chain by reducing production cost and improving environmental performance. Considering the specific situation where there are so many state-owned big company groups in China, this paper utilizes the ideas of constructing an industrial symbiosis among different firms, and does a case study on applying the concept into the inner relationships' reconstruction among different production systems in a big state-owned smeltery in South-west China. Three kinds of approaches are explored: 1) recycling and reusing the release; 2) concentrating and abstracting metals from the residues; 3) extending the product chain for value-added products. The results show that it can effectively improve the competitive advantage of the enterprise in terms of decreasing production cost and improving environmental performance.     

炼钢厂1号—3号转炉煤气回收实践

针对提钒炼钢厂建设于20世纪70年代初的1号—3号转炉实施煤气回收的可能性进行了论证,对影响煤气回收的问题提出了相应的完善措施,在此基础上成功实施了1号—3号转炉煤气回收改造,改进后年回收转炉煤气达2 127 138GJ以上,可发电59 124 kW.h,减少CO2排放量近20万t,对降低生产能耗及减少温室气体排放起到了较好作用。