The national strategy of "Guangdong-Hong Kong-Macao Greater Bay Area" has replaced the original Pearl River Delta economic circle. As one of them, the economic development of Zhaoqing City ushered in a historic opportunity. Other cities in Greater Bay Area provide sufficient tourist resources for the development of Zhaoqing’s tourism industry. Under the new situation, Seven Star Cave, the leading scenic spot in Zhaoqing, should firmly grasp the national strategic dividend of the "Guangdong-Hong Kong-Macao Greater Bay Area", accelerate the transformation and upgrading, and enhance the market competitiveness. In this paper, the data are collected by nominal group technique, and are integrated into SWOT matrix for analysis. The development strategy of Zhaoqing Seven Star Cave Scenic Area is obtained by matching internal and external factors.
In early 2022,two snowfalls of different magnitudes occurred in southern Jiangsu and Anhui,which had different impacts on the operation of Nanjing Airport. Based on NCEP reanalysis data and the WRF3.9 model,the weather condition and the physical quantity fields of two different situations were mainly compared and analyzed. The results show that the snowstorm occurred in the left front of the low-level jet stream and in the wind speed convergence area of the 700 h Pa shear line. The reasonable configuration of the convergence area of the water vapor flux divergence and the rising motion field can be regarded as an important reason for the occurrence of the snowstorm. Through the comparative analysis of these two snowfalls of different magnitudes,the focus of the short-term forecast of heavy snowfall at Nanjing Airport was preliminarily drawn:the 0℃line at 700 h Pa basically pressed southward to the south of 31°N,and the 0℃line at 850 h Pa pressed southward to the south of 30°N. Surface temperature was≤0℃，and temperature at 925-800 h Pa was≤-3 or-4℃; temperature at 700 h Pa was ＜0℃，and there was temperature inversion in the middle and lower troposphere.In the model forecast output field,the proportion of the mixing ratio of frozen precipitation in the near-surface atmosphere to the mixing ratio of water vapor that can condense into precipitation is very important,and can be used to determine the evolution of rain and snow boundaries and sleet areas or the south of rain and snow transition zone and precipitation phase.
To the electronics wastewater with high salinity,the fouling propensity of effluent from the membrane bioreactor( MBR) system played an important role for the design and long-term operational sustainability of the MBR + Reverse Osmosis( RO) system. In this text,the effluent quality,settling performance and membrane fouling were researched with three dimension excitation-emission fluorescence spectra( EEM) and scanning electron microscope( SEM)-Energy Dispersive Spectrometer( EDS). The results showed that there were few organics with a strong adhesion in the effluent. The metal ions in the effluent not only had a complexation reaction with the macromolecules fulvic acid and protein but also with silicon colloid. It caused a compact fouling layer on the RO membrane surface. But the organics and most of inorganic matters could form settling of flocs and be removed from the effluent by improving p H of the effluent,which would relieve the membrane fouling. In addition,the removal of metal ions in the fouling layer was critical for enhancing the cleaning efficiency of RO membrane.
Firstly,current situation and main problems of science and technology development of soil and water conservation were analyzed,and then roles of science and technology in soil and water conservation were studied. At last,exploration ways of roles of science and technology in soil and water conservation were proposed.
Microbial fuel cell（MFC） is a device directly converting microbial metabolic power into electricity with the microbial catalysts,which has the advantages of abundant fuel resource,mild reaction condition and high efficiency.Although it is still in experimental stage,the study of factors affecting the performance of MFC in wastewater treatment provides a significant guidance for practical application.The artificial organic wastewater containing sodium lactate was treated with anaerobic microorganisms obtained from anaerobic activated sludge.Factors affecting the performance of MFC and effect of the wastewater treatment are examined.The result shows that electricity production integrated with COD reduction in this reaction.Power density and coulombic yields in a mediator-less microbial fuel cell are examined as a function of initial COD.The influence of DO on COD removal rate and pH value is reduced by consortium.
Based on daily precipitation data at 35 observation stations during the flood season from 1961 to 2012 in Shandong province,temporal and spatial characteristics of rainstorm day and intensity were analyzed by a mathe-matical statistical method.Meanwhile,a mean generating function model was established in an experiment of rain-storm prediction and was used to predict rainstorm.The results show that the rainstorm day and intensity during the flood season from 1961 to 2012 in Shandong province are in a decreasing trend,and both are not statistically signif-icant at the 0.05 level.Annual mean rainstorm days during the flood season are 2.2 days from 1961 to 2012 in Shandong province,and there are two cycles of 3.4 years and 8.0 years.Annual mean rainstorm intensity is 67.8 mm·d -1 ,oscillating with cycles of 2.3 years,3.3 years,6.9 years and quasi-12 years.There are no abrupt changes for rainstorm day and intensity during the flood season from 1961 to 2012 in Shandong province.Particu-larly,the annual mean rainstorm day and intensity during the flood season all decrease from the mid-later 1970s to late 1980s.The rainstorm day and intensity all increase gradually from northwest to southeast in Shandong prov-ince.The high frequency and strong intensity rainstorm events and continuous rainstorm events usually occur in the south of Shandong province,the south and east of Shandong peninsula.Prediction of rainstorm suggests that the mean generating function model can correctly simulate climate trend of rainstorm during the flood season from 2003 to 2012 in Shandong province,and it also has a good ability in the rainstorm prediction.
以4种浓度中药废水胁迫湿地植物茭白,研究其对茭白根系活力、游离脯氨酸含量、谷胱甘肽含量、丙二醛含量、以及超氧化物歧化酶活性、过氧化物酶活性、过氧化氢酶活性、苯丙氨酸解氨酶活性等生理生化指标的影响.结果表明,随着中药废水胁迫浓度的增加,茭白叶片中超氧阴离子含量、谷胱甘肽含量先增后减;丙二醛含量、苯丙氨酸解氨酶活性、根系活力均先降后升;脯氨酸含量逐渐降低,超氧化物歧化酶、过氧化物酶、过氧化氢酶的活性均呈现波动趋势.因而,茭白在中药废水胁迫下表现出较强的抗逆性与耐受性,可以作为人工湿地处理中药废水的主要备选物种之一.
杭州市主城区中东河随城市经济发展污染严重,水体呈现出劣Ⅴ类水质。研究通过对中东河引配水前后连续7年的定点水质监测,以期掌握引配水对中东河水质改善效果。结果显示,引配水对中东河水质有明显改善,溶解氧浓度平均升高1~2倍,氨氮及总磷浓度分别下降60%及65%;在不考虑内外源性污染前提下,引配水量增大（日常配水量2倍）水体溶解氧增加13%,氨氮、总磷及高锰酸钾指数分别降低8%、3%及14%。河道沿岸偷排雨污合流及河道底泥分别是影响引配水持续改善水质的外源及内源因素,降雨期间,河道水体溶解氧急剧下降约95%,氨氮及总磷浓度则可分别升高90%、87%。研究结果可为持续改善中东河水质及河道管理部门制定相关法规政策提供理论依据。
To assess the value of air regulation in Honghu lake wetland, a quantitative study was conducted based on existing literature. Results showed that the total service value of air regulation in Honghu lake wetland was RMB 254.52 million/year, which was 11.6 times of that by previous studies. The Net value of fixed greenhouse gases via wetland plants (including carbon emission value from methane emission conversion into carbon dioxide greenhouse gas effect) was RMB58.50 million/year, the data indicated that the lake wetland was a strong carbon sink. The value of oxygen released by the wetland ecosystem was RMB176.51 million/year, the value of air humidity and temperature regulation was RMB 19.51 million/year. The next value of greenhouse gas fixation by Honghu lake wetland vegetation, the value of released oxygen, and the value of lifting air humidity and temperature regulation, accounted for 22.98%, 69.35%, and 7.7% of the total value of the air regulation services, respectively.
