Correlation Analysis between Well-cellar Early Transplanting of Robust Seedlings and Diseases in Shiyan Tobacco-growing Area

[Objectives]The paper was to investigate the relationship between the well-cellar early transplanting of robust seedlings and the prevalence of diseases in the Shiyan tobacco-growing area.[Methods]The relationship between disease occurrence and meteorological factors during the field growth period was examined by analyzing the prevalence of flue-cured tobacco virus diseases,brown spot,and total disease in the Shiyan tobacco-growing area before(2013-2017)and after(2018-2022)the well-cellar early transplanting of robust tobacco seedlings.[Results]The implementation of a well-cellar early transplanting technique of robust seedlings resulted in a reduction in the average incidence of tobacco virus disease,brown spot,and total disease by 0.83%,8.85%,and 7.91%,respectively,in comparison to the incidence observed prior to early transplanting.These findings suggest that early transplanting can significantly reduce the incidence of flue-cured tobacco diseases.Prior to the well-cellar early transplanting of robust tobacco seedlings,there was a significant(including highly significant)positive correlation between the incidence of brown spot and total disease and precipitation in August and September.The incidence of brown spot and total disease in tobacco plants was found to be significantly positively correlated with May precipitation and significantly negatively correlated with May sunshine hours following the well-cellar early transplanting of robust seedlings.The advancement of the transplanting period by 20 d resulted in a reduction in the growing period of tobacco plants in the field under autumn rains(late August to November)in western China.This effectively circumvented the suitable conditions for disease occurrence and can reduce the incidence of disease.[Conclusions]This study offers a framework for enhancing the quality and efficiency of flue-cured tobacco production in the northwest tobacco-growing area of Hubei.

The Distribution Characteristics of Soil pH Values of Tobacco-growing Areas in Dali City and Its Correlation with Soil Nutrients

[Objective] The aim was to study the distribution characteristics of soil pH values and its correlation with soil nutrients in tobacco-growing areas. [Method] Soil nutrients of 43 samples from tobacco-growing areas in Dali City were analyzed.[Results] The results showed that average pH value of tobacco-planting soil in Dali City was 6.52, soil samples which suited for flue-cured tobacco cultivation accounted for 72.09% of total soil samples. In four soil types of tobacco-growing areas, the pH values in a descending order were as follows： alluvial soil〉 paddy soil 〉purple soil〉 red soil. At the altitude range of 1 780-2 200 m, soil pH values showed a gradual decreasing trend. The average contents of soil organic matters were relatively abundant and generally suited for high-quality tobacco cultivation; the average contents of soil alkali-hydrolyzable nitrogen, available phosphorus, exchangeable calcium and exchangeable magnesium were generally at medium and abundant level, however,their rations under the medium level in some tobacco-growing areas were 6.98%,11.63%, 2.33% and 4.65%, respectively; moreover, soil with lower available potassium contents occupied a large proportion, namely 58.14%. [Conclusion] Soil pH values had significant correlation with exchangeable magnesium and exchangeable magnesium, however, they had no significant correlation with other soil nutrients.

Biodiversity Risk and Opportunity Assessment in BAT Cooperative Tobacco-growing Areas

Using the method in Biodiversity Risk and Opportunity Assessment Handbook of British American Tobacco Biodiversity Partnership,we assess biodiversity risks and opportunities in BAT and China's cooperative tobacco-growing areas. The assessment results indicate that there are 8 risks and 1 opportunity. Action and monitoring plans have been made for medium and high risks as well as opportunity,to reduce impact on biodiversity.

Study on the Development of Under-forest Economy in Guangdong Mountain Areas

From the origin and connotation of the under-forest economy,this paper analyzed plight of the development of under-forest economy in Guangdong mountain areas. It discussed benefits of under-forest economy,favorable conditions and development path of under-forest economy in Guangdong mountain areas. Results indicate that developing under-forest economy is an essential path for realizing green growth and coordinated development of Guangdong mountain areas. However,due to terrain,market,management and technology reasons,the under-forest economy is still not fully developed in Guangdong mountain areas. The development path of under-forest economy suitable for Guangdong mountain areas should be based on ecological protection and oriented towards maximizing ecological,economic and social benefits. Guangdong mountain areas have in-born natural and resource advantages,economic pull of development mode and market demand change,and favorable condition of policy encouragement for development of under-forest economy. Finally,it came up with recommendations for development of under-forest economy in Guangdong mountain areas from development mode,industrial distribution and development direction.

Zoning Approach of Key Construction Areas of High Standard Capital Farmland in Guangdong Province

On the basis of actual situations of Guangdong Province, using Factor Analysis Approach and Quantitative Analysis Method, we built index system by four factors, namely, extent of farmland connectivity, local financial support, grain production capacity and farmland consolidation potential. Finally, we obtained that the areas with total scores of evaluation higher than 50 points are key construction areas of high-standard capital farmland in Guangdong Province. In total, there are 40 key construction areas, including 16 in plain areas of the Pearl River Delta, 9 in coastal regions of east of Guangdong, 10 in coastal regions of west of Guangdong, and 5 in northwest mountainous regions of Guangdong. Besides, we put forward construction direction of these 4 capital farmland areas.

Study on the Sustainable Development of the Tobacco-growing Area in South Anhui

Based on the actual situation of tobacco production in South Anhui tobacco-growing area,the paper analyzes several major constraints,and discusses several aspects such as tobacco production human resources,production of large-scale cultivation,science and technology service providers,the standardized production management and production security system. The countermeasures and suggestions for sustainable development are also put forward to provide a reference for the sustainable development of tobacco-growing area in South Anhui.

Characteristics of Focal Mechanism in Guangdong and Its Adjacent Areas

The focal mechanisms of 32 earthquakes with magnitude of M_S≥3.0, which were recorded by the Guangdong Digital Seismographic Network, are calculated by using P-wave polarity and amplitude ratio data, and those of 83 earthquakes of Guangdong and its adjacent areas derived by previous researchers are sorted out. On the basis of this, the characteristics of focal mechanism in Guangdong and its adjacent areas are summarized. Meanwhile the focal mechanisms of three earthquake areas, i.e., Yangjiang, Xinfengjiang and Nanao, are discussed respectively. Results show clear regional feature in the function and nature of the stress, and earthquakes are mostly of strike-slip associated with dip-slip component. Earthquakes in the Xinfengjiang Reservoir area are all reservoir-induced ones, so they are only of strike-slip and normal faulting types. In the Yangjiang area, some thrust earthquakes occurred. The dominant orientation of principal compressive stress axis changes from NS in Hainan, Gaungxi to NWW in Guangdong and finally near EW in the coastal areas of Guangdong and Fujian Provinces.

Spatial Variations of b-Values in the Coastal Area of Guangdong

We used earthquake catalogs recorded by Guangdong Seismological Network from 2008 to 2014 to resolve the spatial variations of b-values in the coastal area of Guangdong, particularly in three key research areas(Yangjiang, Heyuan, and offshore Nanao Island) with strong seismicity. Our results revealed that b-values exhibited significant spatial variations, and zones with low b-values could indicate the most likely seismogenic area of large earthquakes. We observed three clear low b-value patches in the offshore Nanao Island. We found a distinct high b-value peak at the depth of 11 km and two minimum peaks at about 14 and 7–8 km in the Yangjiang area. The overall b-values generally decrease with depth in the Heyuan area. The spatial variations of b-values reflect tectonic anomalies; that is, the ‘low-high-low' distribution of b-values in the offshore Nanao Island and the Yangjiang area may indicate the anomaly of the crustal structure with a weak layer. The b-values of reservoir-induced seismicity are obviously lower than that induced by tectonism. This finding indicates that the reservoir area is generally at high stress state under the condition of high pore pressure. We inferred that large earthquakes might be prone to occur at 10–12 km depth in the offshore Nanao Island, at 12–15 km depth in the Yangjiang area, and at the lower part of the seismic activity zone in the Heyuan area. Moreover, the upstream area of the Xinfengjiang reservoir is the most likely area of future large earthquakes in the Heyuan area.

Transport Accessibility and Spatial Connections of Cities in the Guangdong-Hong Kong-Macao Greater Bay Area

Based on geographic information system(GIS) spatial analysis technology, the spatial pattern of raster grid transport accessibility for the Guangdong-Hong Kong-Macao Greater Bay area was studied and the states of spatial connectedness were simulated using highway passenger transport, railway passenger transport, port passenger transport and aviation passenger transport data. The result shows that transport accessibility within the Guangdong-Hong Kong-Macao Greater Bay area costs ‘one hour’ and the spatial distribution of accessibility in the area presents clear ‘core-periphery’ spatial characteristics, with Guangzhou, Foshan, Shenzhen constituting the core. The transport accessibility of Guangdong-Hong Kong-Macao is high. Average accessibility of urban nodes as measured by travel time is 0.99 h, and the areas accessible within 1.42 h occupy 79.14% of the total area. Most of the areas with the lowest accessibility are found in the peripheral area, with the worst accessibility being 4.73 h. Compared with the west-side cities, the economically developed east-side cities of the Guangdong-Hong Kong-Macao Greater Bay area have higher connectivity with roads, railways, ports, and aviation transport. Guangzhou, Foshan, Zhuhai, Shenzhen, Hong Kong and Macao are closely linked. The higher the accessibility, the closer the intercity connectedness.

Kaolin Deposits of Weathering-Residual in the Coastal Area of Guangdong Province

Kaolin deposits of weathering-residual type make up a large proportion in different types of kaolin depos-its and are widely used in ceramics, electron ceramics, rubber and paper industries. This paper discusses sys-tematically this type of kaolin deposit with respect to their features of occurrence, mineralogical and chemicalcomposition and transformation of minerals during supergene processes, thus providing some basic data forthe rational exploitation and utilization of the kaolin resources.

Development of International Education Industry in the Guangdong-Hong Kong-Macao Greater Bay Area

Building the Greater Bay Area city cluster is a crucial national development strategy for China.As a vital hub of the Belt and Road Initiative,the Greater Bay Area cannot cultivate into an“international first-class bay area and world-class city cluster”without technological innovation and rapid economic progress,and technological innovation and economic development cannot be attained without the training of high-end talents through international education.Thus,the development of an international education demonstration zone is essential in the formation and development of the Greater Bay Area and making it a highland for education and talent,as well as giving full play to the social function of education.As the core of the accumulation of educational resources in Guangdong,Hong Kong,and Macao,the current situation,future opportunities,and development path of international education development in the Greater Bay Area while building a world-class international education center have become the starting point of this study.

脑血管疾病风险人群湿证相关特征的流行病学调查

【目的】探究广东地区脑血管疾病风险人群与中医湿证相关的流行病学特征。【方法】采用横断面研究的方法,调查330例广东常住居民脑血管疾病风险相关的临床资料,进行中医湿证诊断、量化评分及脑卒中风险评级,总结湿证分布规律并分析其影响因素。【结果】(1)诊断为湿证的研究对象共306例(占92.73%),风险组诊断为湿证人群的占比为93.82%(258/275),略高于健康组的87.27%(48/55),但差异无统计学意义(χ2=2.91,P=0.112),而风险组的湿证量化得分高于健康组,差异有统计学意义(Z=-2.24,P=0.025)。(2)在具有脑血管疾病危险因素的研究对象中,评价时间(χ2=26.11,P=0.001)、脑卒中风险等级(χ2=8.85,P=0.031)、脑卒中或短暂性脑缺血发作(TIA)病史(χ2=9.28,P=0.015)是脑血管病风险人群湿证等级的影响因素。【结论】湿证是广东地区人群常见的中医证候;具有脑血管疾病危险因素,尤其是脑卒中高风险人群、脑卒中或TIA病史患者,其湿证程度明显增高;未来在广东开展脑卒中预防工作应考虑湿证的评估与干预。

从场空间到流网络:粤港澳大湾区城市群空间结构特征及优化路径研究

检视粤港澳大湾区城市群空间结构演化趋势,对纵深推动大湾区高质量发展意义重大。本研究因应数字经济对区域要素流动结构的影响,提出粤港澳大湾区“流网络”分析框架,并以首位度和齐普夫法则测度传统空间结构特征,以上市企业的“总部—分支”机构分布测度流网络特征。结果表明:大湾区总体经历了先集聚再分散的发展过程;各城市人口分布梯度不合理,核心城市的人口扩张推动了城市群的定型。大湾区经济规模结构呈现帕累托分布模式,各城市经济规模变差较大。从城际联系来看,广州深圳之间具有高联通度,形成了联通走廊,2000年以来深圳的相对联通度高居首位,区域网络日渐完善。未来,应织密高效的综合交通网络,加速市场一体化进程、构建“双核三圈”网络型城市群体系、设立“广深接合片区”并加快打造“广深联动走廊”,开创大湾区高质量协同发展新格局。

城市群人口集聚对共同富裕的影响——基于粤港澳大湾区的分析

共同富裕是中国式现代化的重要特征和中国特色社会主义的本质要求,如何推进共同富裕目标的实现成为政府和学界亟待解决的难题。以粤港澳大湾区为样本探讨城市群人口集聚对城市群内部以及周边区域共同富裕的影响,在理论分析的基础上采用“全面FGLS”方法以及动态面板空间杜宾模型进行估计得到如下结论:粤港澳大湾区人口集聚无论是对于城市群内部共同富裕还是带动周边区域共同富裕均具有积极的促进作用,在短期内存在正向的空间溢出作用,但长期而言粤港澳大湾区人口不可能无限集聚,当发展到一定程度后拥挤效应将超过集聚效应对共同富裕产生负面影响。上述结论意味着当前粤港澳大湾区内部形成的多中心集聚的态势,空间协调发展程度较高,在推动城市群内部共同富裕的同时,短期内也带动了周边区域的发展,但长期持续的发展仍需人口在粤港澳全域更为均衡地分布,而非无限向粤港澳大湾区集聚。基于上述结论,提出应重视基础设施的互联互通、产业互联、城市互联等,促进粤港澳大湾区与粤东西两翼及山区人口等要素资源更为顺畅地流动,优化资源配置,促进粤港澳全域发展,实现真正意义上的先富带动后富,最终实现共同富裕。

大湾区如何先行先试国际高标准经贸规则

与WTO相关规则对比分析发现,CPTPP等国际高标准经贸规则在全球价值链分工、数字贸易、“边境(后)”规则等方面进行拓展和完善,从经济领域和规则领域两个层面对中国产生诸多影响。结合粤港澳大湾区的发展实际,粤港澳大湾区可在非关税壁垒领域(削减非关税壁垒,对标国际高标准)、服务贸易领域(促进服务贸易高水平自由化)、国有企业和指定垄断领域(营造企业公平竞争的制度环境)、数字贸易领域(审慎管理数据要素,统筹好开放与安全)、中小企业领域(推动中小企业转型升级,提升竞争力)先行先试部分国际高标准经贸规则,为中国改进经贸规则,提出国际经贸规则的“中国模板”提供智力支持。

粤港澳大湾区绿色创新效率时空演化与影响因素研究

基于Super-SBM模型对2011—2020年粤港澳大湾区11个城市绿色创新效率进行测算,并运用核密度估计模型、莫兰指数以及冷热点法分析粤港澳大湾区绿色创新效率的时空演化特征,在此基础上采用空间杜宾模型(SDM)探究粤港澳大湾区绿色创新效率的影响因素。研究表明:研究时间区间,粤港澳大湾区绿色创新效率总体处于较高水平,且呈波动上升趋势;粤港澳大湾区绿色创新效率具有显著的空间非均衡性,呈现“东南高、西北低”的空间分异格局,且该格局有加剧趋势,同时空间相关性于2020年由正转负;政府支持、教育水平以及经济水平对粤港澳大湾区绿色创新效率具有显著的促进作用,教育水平对邻近地区的绿色创新效率具有正向溢出效应,而政府支持对邻近地区效率值具有负向溢出效应。

粤港澳大湾区内地高校港籍大学生的国家认同现状及其塑造机制

粤港澳大湾区建设在塑造中国香港青年国家认同方面具有重要意义。以就读于大湾区内地高校的港籍大学生为研究对象,通过访谈和问卷调查发现,大湾区建设背景下内地港籍大学生具有政治认同度较好、文化认同度较高及国民身份认同度较强的国家认同现状。这缘于港籍大学生在大湾区内地求学时,多元主体围绕其发展需求,以政策吸纳、教育合作、人文交流和生活化传播等四种机制,推进该群体的政治社会化场景变迁,进而对其塑造一种正向的国家认同。据此,应在推进大湾区高质量发展的同时,加强制度改革与规则协调,优化国民教育的课程体系及考核方式,加大大湾区建设的普惠性宣传,借以发挥大湾区在塑造广大中国香港青年国家认同的政策效能。

数字经济产业区域协同发展机理及路径研究--基于江西与粤港澳、长三角、长江中游城市群协同发展视角

数字经济产业区域协同发展对推动区域经济效率变革、质量变革和动力变革具有积极推动作用。近年来,江西充分发挥毗邻粤港澳大湾区、长三角以及位居长江中游城市群的地理优势,积极推动数字经济产业区域协同发展,打造了赣深电子信息产业集聚区、承接长三角数字产业转移示范区、赣湘电子信息产业园等,为江西数字经济产业高质量发展奠定了扎实基础,但是在数字经济产业区域协同发展过程中仍然存在协同规划缺乏、协同层次偏低、协同结构失衡、产业数字化滞后、数字技术协同创新弱和数据要素共建共享不畅等问题。这需从强化规划引领、提高协同层次、优化协同结构、加快数字化转型、推动数字技术协同创新和促进数据互联互通共用等方面加以破解。

全球海洋中心城市的湾区实践——以粤港澳大湾区为例

粤港澳大湾区是加快实施海洋强国战略的重要支点,全球海洋中心城市建设则是进一步推动粤港澳大湾区建设的关键抓手。全球海洋中心城市作为当前海洋城市建设与评价最具影响力的目标对象,需要分别在全球与湾区视角下考察粤港澳大湾区的优势与挑战。本研究通过解读全球海洋中心城市的概念与内涵,剖析了典型全球海洋中心城市的显著特征,以及与国际一流湾区发展的关系。研究发现,粤港澳大湾区在全球海洋中心城市数量和航运物流方面具有优势,但是在海事技术、竞争力与吸引力等方面面临巨大的竞争挑战。粤港澳大湾区推进全球海洋中心城市建设,着重要加快提升国际航运能力、加强海洋科技创新、参与全球海洋治理、强化海洋战略规划等。