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Construction Features of Small Roadside Parks in Tropical Area——A Case Study of Zhanjiang City 被引量:1
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作者 HUANG Yanna WU Liuping 《Journal of Landscape Research》 2013年第5期14-16,共3页
Accessibility and flexibility of small roadside parks make them significant transitional spaces in urban landscape environment. Three representative small parks in Zhanjiang City, a typical tropical city in south Chin... Accessibility and flexibility of small roadside parks make them significant transitional spaces in urban landscape environment. Three representative small parks in Zhanjiang City, a typical tropical city in south China, were selected to analyze their location features, spatial processing, demonstration of regional landscapes and recreational characteristics. It was proposed that construction of small roadside parks in tropical area should put human needs on the priority, present regional features of tropical garden landscapes, and focus on inheritance and innovation of regional cultures. 展开更多
关键词 SMALL ROADSIDE parks RECREATIONAL FEATURES Regional landscapes TROPICAL gardens zhanjiang CITY
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Isotope constraints on seasonal dynamics of nitrogen in Zhanjiang Bay, a typical mariculture bay in South China
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作者 Chunqing Chen Qibin Lao +3 位作者 Fajin Chen Guangzhe Jin Jiacheng Li Qingmei Zhu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期60-70,共11页
Eutrophication in coastal waters has been increasing remarkably,severely impacting the water quality in mariculture bays.In this study,we conducted multiple isotopic measurements on suspended particulate nitrogen(δ^(... Eutrophication in coastal waters has been increasing remarkably,severely impacting the water quality in mariculture bays.In this study,we conducted multiple isotopic measurements on suspended particulate nitrogen(δ^(15)N-PN) and dissolved nitrate(δ^(15)N-NO_(3)^(-)and δ^(18)O-NO_(3)^(-)) in Zhanjiang Bay,a typical mariculture bay with a high level of eutrophication in South China,to investigate the changes in nitrogen sources and their cycling between the rainy and dry seasons.During the rainy season,the study found no significant relation between δ^(15)NPN and δ^(15)N-NO_(3)^(-)due to the impact of heavy rainfall and terrestrial erosion.In the upper bay,a slight nitrate loss and slightly higher δ_(15)N-NO_(3)^(-)and δ^(18)O-NO_(3)^(-)values were observed,attributed to intense physical sedimentwater interactions.Despite some fluctuations,nitrate concentrations in the lower bay mainly aligned with the theoretical mixing line during the rainy season,suggesting that nitrate was primarily influenced by terrestrial erosion and that nitrate isotopes resembled the source.Consequently,the isotopic values of nitrate can be used for source apportionment in the rainy season.The results indicated that soil nitrogen(36%) and manure and sewage(33%) were the predominant nitrogen sources contributing to nitrogen loads during this period.In contrast,the dry season saw a deficient ammonium concentration(<0.2 μmol/L) in the bay,due to nearly complete consumption by phytoplankton during the red tide period.Additionally,the significant loss of nitrate and simultaneous increase in the stable isotopes of dissolved and particulate nitrogen suggest a strong coupling of assimilation and mineralization during the dry season.More active biogeochemical processes during the dry season may be related to decreased runoff and increased water retention time.Overall,our study illustrated the major seasonal nitrogen sources and their dynamics in Zhanjiang B ay,providing valuable insights for formulating effective policies to mitigate eutrophication in mariculture bays. 展开更多
关键词 NITROGEN stable nitrogen isotopes biogeochemical processes EUTROPHICATION zhanjiang Bay
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Distribution and sources of sedimentary organic matter in different aquaculture areas of northeastern Zhanjiang Bay using stable carbon and nitrogen isotopes
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作者 Fengxia Zhou Shuangling Wang +8 位作者 Han Fang Jiani He Liang Ye Zhaohai Ding Cuiting Li Fajin Chen Xuan Lu Chunqing Chen Yafei Meng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期38-48,共11页
Zhanjiang Bay is a major aquaculture area in China with many types of mariculture products(such as oysters,fish,and shrimp).The culture area and shrimp output in Zhanjiang Bay are ranked first in China.We investigated... Zhanjiang Bay is a major aquaculture area in China with many types of mariculture products(such as oysters,fish,and shrimp).The culture area and shrimp output in Zhanjiang Bay are ranked first in China.We investigated the total organic carbon(TOC),total nitrogen(TN),TOC/TN ratio,and stable isotopes(δ^(13)C and δ^(15)N) of the fish and shrimp feed,fish and shrimp feces,and sedimentary organic matter(SOM) in and around different aquaculture areas of northeastern Zhanjiang B ay to study the impact of aquaculture activities on SOM.The average TOC contents of fish and shrimp feed were 39.20%±0.91% and 39.29%±0.21%,respectively.The average TOC content in the surface sediments of the oyster culture area,the mixed(fish and shrimp) culture area,and the cage fish farm area were 0.66%,0.88%±0.10%,and 0.58%±0.19%,respectively,which may indicate that mixed culture had a greater impact on SOM.The relatively high TOC and TN contents and relatively low TOC/TN ratios,and δ^(15)N values in the upper layer of the core sediment in the mixed culture area could also support the significant influence of mixed culture.The average δ^(13)C and δ^(15)N values of fish and shrimp feed were -20.6‰±2.2‰ and 1.8‰±1.2‰,respectively,which were different from the isotopic values of SOM in the study area.δ^(13)C and δ^(15)N values for SOM in different aquaculture areas were different from those of nearby reference stations,probably reflecting the influence of aquaculture.The δ^(13)C and δ^(15)N values in the oyster culture area(-25.9‰ and6.0‰,respectively) seemed to have reduced δ^(13)C and enriched δ^(15)N relative to those of the reference station(-24.6‰ and 5.8‰,respectively).This may reflect the influence of organic matter on oyster culture.The δ^(15)N value of the station in the mixed culture area(7.1‰±0.4‰) seemed to be relatively enriched in δ^(15)N relative to that of the reference station(6.6‰).Sedimentation and the subsequent degradation of organic matter from mixed cultures may have contributed to this phenomenon.The surface sediment at the cage fish farm area seemed to be affected by fish feces and primary production based on the indication of δ^(13)C and δ^(15)N values.The sediment core at the mixed culture region(NS6) had lower TOC/TN ratios and more positive δ^(13)C and δ^(15)N values than the sediment core at the oyster culture area,suggesting a higher proportionate contribution of marine organic matter in the mixed culture area.In summary,oyster culture,mixed culture,and cage fish culture in northeastern Zhanjiang Bay had a certain degree of impact on SOM,and mixed culture had more significant influences on SOM based on the high TOC contents and the significant vertical variations of TOC/TN ratio and δ^(15)N value in the sediment of this area.This study provides new insights into the impact of aquaculture activities on SOM content. 展开更多
关键词 sedimentary organic matter AQUACULTURE stable isotopes SOURCES zhanjiang Bay
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Numerical Study of the Donghai Dam Impact on the Hydrodynamic Environment of Zhanjiang Bay 被引量:3
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作者 李希彬 孙晓燕 +1 位作者 于华明 鲍献文 《Marine Science Bulletin》 CAS 2010年第1期16-29,共14页
In this paper, the Finite Volume Coastal Ocean Model (FVCOM) was employed and configured for 3 dimensional numerical simulations of tide and tidal current based on the field observations in Zhanjiang Bay. The model... In this paper, the Finite Volume Coastal Ocean Model (FVCOM) was employed and configured for 3 dimensional numerical simulations of tide and tidal current based on the field observations in Zhanjiang Bay. The model's results agree well with the field observed data. Based on the well validated model, the hydrodynamic fields of zhanjiang bay area were calculated both before the Donghai Dam constructing and after that. Compared the tidal level, current field, tidal capacity and water exchange ratio before the construction of Dohai dam with those after construction of the dam, we analyzed and get some conclusions of effects of Donghai Dam on Hydrodynamic environment of the Zhanjiang Bay. 展开更多
关键词 zhanjiang bay Donghai dam numerical model hydrodynamic environment
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Investigation of Export Aquaculture in Zhanjiang City and Development Suggestions
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作者 Liang Tianjiao Ye Shengquan +1 位作者 Lao Tongfen Wang Yu 《Animal Husbandry and Feed Science》 CAS 2014年第6期308-311,共4页
History of aquaculture in Zhanjiang City was reviewed by reviewing literatures, human resources, cultured species and culture modes, and distribution of aquaculture system were investigated and summarized. Output and ... History of aquaculture in Zhanjiang City was reviewed by reviewing literatures, human resources, cultured species and culture modes, and distribution of aquaculture system were investigated and summarized. Output and export of processed aquatic products of Zhanjiang in the past years were analyzed, and the role of export aquaculture in economic development and social construction of Zhanjiang City was explored, and suggestions were given for enhancing the development of local export aquaculture. 展开更多
关键词 zhanjiang EXPORT AQUACULTURE INVESTIGATION SUGGESTION
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Independent integration of the 300 t BOF of Zhanjiang in heritage of steelmaking technologies of Baosteel
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作者 ZHU Konglin and SUN Liming Baosteel Engineering & Technology Group Co.,Ltd.,Shanghai 201900,China 《Baosteel Technical Research》 CAS 2010年第S1期107-,共1页
Through summary and extraction of current steelmaking design,process and equipment technologies and production technologies for 300 t grade converters in Baosteel,the article analyzes and elaborates the significance o... Through summary and extraction of current steelmaking design,process and equipment technologies and production technologies for 300 t grade converters in Baosteel,the article analyzes and elaborates the significance of independent integration of 300 t grade converters in Zhanjiang,major targets of the independent integration in converter process technologies,equipment packages and controls,the innovated critical technologies and comparison with overseas advanced technologies,major technical difficulties in the integration in Baosteel and their solutions,as well as general mindset and final objectives of the project.The total integration of technology for Shanghai No.1 Steel Making Plant of Baosteel was undertaken by Nippon Steel.And Kawasaki Steel was responsible for the total integration of technology for 4# and 5# converters of Shanghai No.2 Steelmaking Plant of Baosteel.Based on digestion,absorption and innovation of the introduced technologies,Baosteel has firstly achieved the independent integration of 6# converter,5# RH and 3# LF projects in the Shanghai No.2 Steelmaking Plant of Baosteel.Therefore, Baosteel shall take advantages of the favorable conditions and experiences and advanced steel making technologies of Baosteeel to master the imported new steelmaking technologies in the world and then form the advanced complete set steel making technologies and equipment at home and abroad.The achievement of independent integration of Zhanjiang Steel Making Project will make the breakthrough for the construction of large - sized steel making plant in Baosteel.300 t converter technology integration is undertaken by Baosteel independently in instead of by the foreign side in the past. 展开更多
关键词 Baosteel BOF steelmaking technology 300 t BOF of zhanjiang independent integration
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Residues and sources of HCHs and DDTs in the sediments of land-based sewage outlet to the Zhanjiang Bay, China
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作者 Lirong Zhao Yuzhen Shi +2 位作者 Hui Zhao Jibiao Zhang Xingli Sun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第12期8-13,共6页
Due to the large usage of DDT-containing antifouling paints and lindane in China, heavy residuals of DDTs and HCHs have been found in many fishing harbors, but there is lack of studies on this issue for the Zhanjiang ... Due to the large usage of DDT-containing antifouling paints and lindane in China, heavy residuals of DDTs and HCHs have been found in many fishing harbors, but there is lack of studies on this issue for the Zhanjiang Bay which is an important fishing harbor and mariculture zone in South China. To evaluate the pollution status and sources of HCHs and DDTs in the Zhanjiang Bay, the concentrations, spatial distributions and sources in the sediments of 11 land-based sewage outlets to the Zhanjiang Bay were investigated. Since the 1980 s, HCHs residuals had obviously decreased in studied areas, but DDTs had little change, even abnormally high levels were found in some sites. The content percentages and diagnostic ratios of HCHs isomers and DDTs showed that the source of HCHs was derived from soils around the bay and recent input of lindane, and DDTs were from historical residues of technical DDTs and fresh input of DDT-containing antifouling paints on fishing ships. Based on sediment quality guidelines, DDTs would be of more concern for the ecotoxicological risk on marine environment and adverse effects on benthonic organisms. This study indicated that lindane and DDT-containing products may be still used in some places of Zhanjiang City. It should be urgent to control their usage and clean the DDTs-contaminated sites by the local government. 展开更多
关键词 zhanjiang Bay SEDIMENT DDTS HCHS
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Development Status and Policy Path of Cultivating Marine Bio-industry Cluster in Zhanjiang City
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作者 Nan ZHAO Fuchen BAI 《Asian Agricultural Research》 2018年第9期23-28,共6页
Cultivating the marine bio-industry cluster is a key industrial strategy for Zhanjiang to seize the manufacturing position of Guangdong's marine economy. By deconstructing the overall scale,characteristics and ind... Cultivating the marine bio-industry cluster is a key industrial strategy for Zhanjiang to seize the manufacturing position of Guangdong's marine economy. By deconstructing the overall scale,characteristics and industrial composition of marine bio-industry cluster and the development status of the industrial parks and bases in Zhanjiang,the resource misallocation coefficient was used to analyze the problems in the marine bio-industry cluster and the resource allocation in Zhanjiang. It is found that in the cultivation of the marine bio-industry cluster in Zhanjiang,the leading effect of leading enterprises needs to be upgraded,the key technologies needs to be broken,the scientific and technological service system needs to be improved,and policy support needs to be strengthened. Moreover,there are serious resource misallocation and high efficiency losses. By optimizing resource allocation,the healthy development of cultivation of marine bio-industry cluster in Zhanjiang will be promoted. To this end,the policy paths that the government can implement are as follows: improving the market access system to appropriately guide medium and small-sized marine enterprises to enter the marine bio-industry,inspiring the marine bio-industry market demand with the industrialization of innovation results as the guide,improving the legal guarantee system to create an innovative atmosphere for the marine bio-industry,and promoting the deepening of the division of labor in the industrial parks. 展开更多
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Study on the Perceived Value of Zhanjiang Residents to Mangrove Cuisine
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作者 DENG Yuping HUANG Yafen 《Psychology Research》 2023年第6期266-275,共10页
Taking mangrove cuisine in Zhanjiang as an example,this paper investigates the residents’perceived value of mangrove cuisine through questionnaire survey.The results show that the overall satisfaction of residents on... Taking mangrove cuisine in Zhanjiang as an example,this paper investigates the residents’perceived value of mangrove cuisine through questionnaire survey.The results show that the overall satisfaction of residents on the mangrove cuisine in Zhanjiang is high.The highest satisfaction of residents on the perceived value of mangrove cuisine is the historical and cultural heritage,and the lowest satisfaction is the local characteristics.The main factor affecting the satisfaction is the utility value.Based on the analysis of the present situation and existing problems of mangrove cuisine resources in Zhanjiang,this paper puts forward some countermeasures and suggestions for the sustainable development of mangrove food in Zhanjiang in terms of strengthening government support,increasing public participation awareness,increasing publicity channels,enhancing popularity and reputation,and paying attention to the inheritance of characteristic food culture. 展开更多
关键词 zhanjiang residents mangrove cuisine perceived value questionnaire survey
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Practice and Innovation of "Teacher Education" Training Mode: Take Zhanjiang Normal University for Example
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作者 Chen Qiongying Zeng Bo 《Review of Global Academics》 2014年第4期293-300,共8页
This article adopts the method of case study, thorough analysis of Zhanjiang Normal University in teacher education training model innovation practice, explore its talent training innovation goals: to cultivate beaut... This article adopts the method of case study, thorough analysis of Zhanjiang Normal University in teacher education training model innovation practice, explore its talent training innovation goals: to cultivate beauty, intelligence and physique full scale development "responsible, strong ability, good innovation". Came to the conclusion that the university talents training mode of innovative practice is specific to subjects and to students. 展开更多
关键词 Teacher education Talent training mode INNOVATION zhanjiang Normal University
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试论湛江市园林植物景观热带特色的营造 被引量:14
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作者 吴刘萍 李敏 《福建林业科技》 北大核心 2005年第2期106-110,115,共6页
优美而富有特色的城市景观是体现和提升城市整体质量的关键因素,建设具有热带风光的园林城市、生态城市是湛江城市建设的目标。通过加强湛江市热带特色植物的选择规划,运用热带特色植物配置的形式和手法,营造出富有热带特色的园林植物景... 优美而富有特色的城市景观是体现和提升城市整体质量的关键因素,建设具有热带风光的园林城市、生态城市是湛江城市建设的目标。通过加强湛江市热带特色植物的选择规划,运用热带特色植物配置的形式和手法,营造出富有热带特色的园林植物景观,从而突显城市的热带风光。 展开更多
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湛江市近十年图书馆事业与社会经济发展的相互关系 被引量:4
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作者 陈连梅 《图书馆论坛》 CSSCI 北大核心 2003年第5期136-138,共3页
通过对湛江市国民经济发展指标和图书馆基本情况的调查 ,说明社会经济发展与图书馆系统之间的相互依存和相互促进关系。
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湛江海域6种常见经济海藻的营养成分分析 被引量:9
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作者 赵素芬 孙会强 +1 位作者 梁钧志 何培民 《广东海洋大学学报》 CAS 2009年第1期49-53,共5页
分析采自湛江海域的粗枝软骨藻Chondria crassicaulis、日本沙菜Hypnea japonica、鱼栖菜Acanthophora sp、芋根江蓠Gracilaria blodgettii、平卧松藻Codium repens、网地藻Dictyota dichotoma等6种经济海藻的营养成分。结果表明:碳水... 分析采自湛江海域的粗枝软骨藻Chondria crassicaulis、日本沙菜Hypnea japonica、鱼栖菜Acanthophora sp、芋根江蓠Gracilaria blodgettii、平卧松藻Codium repens、网地藻Dictyota dichotoma等6种经济海藻的营养成分。结果表明:碳水化合物是这些海藻的主要营养成分,占藻体干重的42.81%~66.11%,平均为55.93%;粗蛋白含量6.63%~11.13%;粗脂肪含量最低,除网地藻D.dichotoma(2.85%)外,其余5种皆不足藻体干重的1%;粗纤维和灰分含量在种间差别较大;矿物质含量丰富,其中磷、铁和锌分别在平卧松藻C.repens、网地藻D.dichotoma和鱼栖菜Acanthophora中占藻体干重的0.093%、0.13%和0.0055%;氨基酸含量较高,其中Thr、Val、Ile、Leu、Phe几种必需氨基酸的含量均高于FAO标准;不少种类中汞、镉、铅、砷等含量超出我国食品卫生标准。海藻体内的营养成分含量因海藻种类和生长海域的不同而有差异。 展开更多
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台风天气湛江钢铁煤气系统安全防御实践
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作者 郑志雁 李雪原 庞鹏飞 《南方金属》 CAS 2024年第2期49-51,共3页
以台风天气期间湛江钢铁的煤气系统如何安全保正压、停复役等为例,结合生产计划,有序安排煤气系统停复役及通过COG和氮气合成煤气、煤气柜储气等来保证台风天气期间的所需煤气,从而保证了台风等极端天气条件下的煤气系统安全稳定。
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商业保险参与社会医疗保障的现实模式与发展方向 被引量:4
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作者 吴海波 何冲 《西部论坛》 2014年第5期52-58,共7页
我国商业保险自21世纪初期开始进行参与社会医疗保障经办服务的探索,各地的实践先后形成了商业保险参与社会医疗保障的"委托管理模式""保险合同模式""共保联办模式"等,每种模式均有其特色与优势,也存在... 我国商业保险自21世纪初期开始进行参与社会医疗保障经办服务的探索,各地的实践先后形成了商业保险参与社会医疗保障的"委托管理模式""保险合同模式""共保联办模式"等,每种模式均有其特色与优势,也存在瑕疵与不足。未来的"政保合作"方向应是"双重一体化委托管理模式",即:打破城乡二元结构,建立城乡一体的医疗保障体系;商业保险以"委托管理模式"参与城乡居民基本医疗保险,以"保险合同模式"参与城乡居民大病医疗保险,实行"基本+大病"一体化管理。 展开更多
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广东湛江烟区不同雪茄品种综合性状评价
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作者 舒佳惠 邹明民 +8 位作者 马柱文 伍彩云 陈桢禄 谭宇劲 余安 李章晓 李集勤 潘晓英 黄振瑞 《广东农业科学》 CAS 2024年第4期79-88,共10页
【目的】综合评价不同雪茄品种的生态适应性,筛选适宜广东湛江烟区种植的雪茄品种。【方法】对8个新引进雪茄品种进行田间试验,分析比较其大田生育期、农艺性状、田间自然发病率、常规化学成分和感官质量评吸的差异,利用综合指数法对其... 【目的】综合评价不同雪茄品种的生态适应性,筛选适宜广东湛江烟区种植的雪茄品种。【方法】对8个新引进雪茄品种进行田间试验,分析比较其大田生育期、农艺性状、田间自然发病率、常规化学成分和感官质量评吸的差异,利用综合指数法对其进行综合性状评价。【结果】8个雪茄品种的大田生育期均较长、平均为141.63 d,且品种间差异较大。其中,‘海研108’和‘海研201’大田生育期最短(均为133 d)、‘云雪8号’最长(155 d)。农艺性状以‘云雪8号’和‘海研200’综合表现最好,2个品种的株高、最大叶宽、节距和有效叶数均优于8个品种的平均水平,表明这2个品种的田间生长势强。‘海研200’‘海研101’和‘云雪2号’的烟草普通花叶病发生率均较低,介于5.09%~6.85%,且均无烟草气候斑点病发生,表明这3个品种的抗病性较强;常规化学成分协调性以‘海研200’和‘海研101’较好,综合得分均高于平均水平,但2个品种的钾氯比均低于优质烟叶适宜范围(4~10)。感官质量评吸以‘海研101’得分最高(46.07),特点是香气量稍足、余味尚干净、回甜感较强和燃烧性较好。综合指数计算结果显示,8个雪茄品种的得分排序为:‘海研200’>‘海研101’>‘云雪8号’>‘云雪2号’>‘海研108’>‘海研201’>‘云雪3号’>‘Havana’。【结论】8个新引进雪茄品种中,‘海研200’和‘海研101’的综合性状较好,适宜在湛江烟区引进种植,建议通过优化施肥方案、晾制与发酵工艺进一步提高烟叶质量。 展开更多
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湛江市古树资源特征分析
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作者 谢继红 郭乐东 +1 位作者 赵奕 黄华毅 《桉树科技》 2024年第1期57-63,共7页
为摸清湛江市古树资源情况,加强湛江市古树保护工作,基于广东省古树名木普查成果数据,对湛江市古树资源的树种结构、树龄、分布、生长环境、生长状况等方面进行了分析。结果表明:湛江市共有古树7356株,隶属于46科84属111种;在湛江各县... 为摸清湛江市古树资源情况,加强湛江市古树保护工作,基于广东省古树名木普查成果数据,对湛江市古树资源的树种结构、树龄、分布、生长环境、生长状况等方面进行了分析。结果表明:湛江市共有古树7356株,隶属于46科84属111种;在湛江各县级市、县区均有分布,其中徐闻县古树数量最多;优势树种主要是榕树(Ficusmicrocarpa)、垂叶榕(F.benjamina)、鹊肾树(Streblusasper)、樟(Camphoraofficinarum)等观赏树种和龙眼(Dimocarpuslongan)、荔枝(Litchi chinensis)等果树;古树生长场所主要为乡村,树龄主要分布在100~200年之间,三级古树多达7080株,占比96.25%;古树树高主要分布范围是7~20 m,平均树高为12.97 m,胸径主要分布范围是40~160 cm,平均胸径96.7 cm,冠幅主要分布范围4~20 m,平均冠幅13.55 m。总体而言,湛江市古树生长环境和生长势良好,古树资源物种多样性丰富。 展开更多
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基于时序遥感的撂荒地监测及空间格局特征分析
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作者 肖文菊 杨颖频 +1 位作者 吴志峰 郑少兰 《热带地理》 CSCD 北大核心 2024年第3期547-556,共10页
针对耕地撂荒监测的迫切需求,文章发展了一种基于光学时序特征的撂荒地遥感识别方法,利用Sentinel-2时间序列数据构建耕地NDVI时序曲线,基于撂荒地和非撂荒耕地NDVI在监测时间窗口内的振幅差异,通过F1指数迭代式选取撂荒地识别的最佳振... 针对耕地撂荒监测的迫切需求,文章发展了一种基于光学时序特征的撂荒地遥感识别方法,利用Sentinel-2时间序列数据构建耕地NDVI时序曲线,基于撂荒地和非撂荒耕地NDVI在监测时间窗口内的振幅差异,通过F1指数迭代式选取撂荒地识别的最佳振幅分割阈值,构建撂荒地识别规则,并在广东省湛江市坡头区开展耕地撂荒监测试验,分析撂荒地块的景观格局特征。研究表明:1)对比撂荒地与非撂荒地的NDVI时序曲线形态发现,撂荒地全年NDVI时序曲线变化平缓,变化幅度较小;非撂荒耕地由于作物生长发育的物候过程,NDVI时序呈现较大的变化幅度。2)通过迭代式选取振幅分割阈值,撂荒地与非撂荒地NDVI振幅的最佳分割阈值为0.42,在该分割阈值下,撂荒地和非撂荒地的识别精度分别为91.83%和90.20%。3)对撂荒地景观格局特征分析结果表明,2020年坡头区耕地撂荒面积为14.65 km^(2),约占耕地总面积的10.1%,撂荒地块普遍面积较小、形状不规则,空间上分布零散,少有大面积撂荒现象。 展开更多
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湛江港水产养殖区水体氮磷含量及潜在性营养化程度分析 被引量:11
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作者 陈伟珍 林轩 +1 位作者 邓秀清 方蕾 《海洋渔业》 CSCD 2004年第2期99-102,共4页
根据2001年夏、秋两季对湛江港特呈岛网箱养殖场和东海岛文参虾塘两个养殖区海水营养盐(DIN、DRP)含量的监测结果,报道了其含量变化特征及潜在性富营养化程度。结果表明:该水体DIN含量严重超标,网箱养殖场的DRP平均值也超标,池塘养殖场... 根据2001年夏、秋两季对湛江港特呈岛网箱养殖场和东海岛文参虾塘两个养殖区海水营养盐(DIN、DRP)含量的监测结果,报道了其含量变化特征及潜在性富营养化程度。结果表明:该水体DIN含量严重超标,网箱养殖场的DRP平均值也超标,池塘养殖场的DRP符合第二类海水水质标准,这两个养殖区水体均属于磷限制潜在性富营养化。 展开更多
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有机肥配施赤霉素和混合芽孢杆菌对柑橘黄龙病的作用
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作者 王立 刘颖 +5 位作者 张逸东 魏文康 刘勤坚 陈华胜 罗敏 俞婷 《中国土壤与肥料》 CAS CSCD 北大核心 2024年第8期221-232,共12页
比较有机肥配施微生物菌剂、赤霉素对柑橘黄龙病菌的含量、土壤有机质及土壤微生物群的影响,为柑橘黄龙病的治疗和柑橘土壤肥力提升提供科学依据。从柑橘叶片内生菌中分离得到枯草芽孢杆菌,设置有机肥配施复合芽孢杆菌剂、25 mg/L赤霉... 比较有机肥配施微生物菌剂、赤霉素对柑橘黄龙病菌的含量、土壤有机质及土壤微生物群的影响,为柑橘黄龙病的治疗和柑橘土壤肥力提升提供科学依据。从柑橘叶片内生菌中分离得到枯草芽孢杆菌,设置有机肥配施复合芽孢杆菌剂、25 mg/L赤霉素的病株为处理组,另一组为对照,对柑橘黄龙病菌含量、土壤有机质及土壤微生物进行比较分析。与对照组相比,有机肥配施复合芽孢杆菌、赤霉素处理柑橘的带菌量显著下降,黄龙病在荧光定量PCR扩增中从基线到指数增长的拐点所对应的循环次数(Ct值)从初始的25.10增加到了31.46,土壤有机质和速效钾分别提高了22.0%和102.0%。复合芽孢杆菌分泌出的代谢产物既能抑制病菌的生长,还能通过建立优势益生菌群优化土壤结构,促进根系生长,有效解决营养输送的问题,恢复病树状态。有机肥配施复合芽孢杆菌和赤霉素对改善柑橘黄龙病,提高土壤有机质、速效钾等有显著促进作用。 展开更多
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