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11.
Benjamin S. Lowe Susan K. Jacobson Happiness Anold Athanasio S. Mbonde Kai Lorenzen 《Fish and Fisheries》2019,20(5):1024-1033
Religion and spirituality have long played important roles in fishery systems around the world, and yet are often neglected in modern fisheries management and research. We review current literature and analyse the major small‐scale fishery on Lake Tanganyika, Africa, to highlight how religion may mediate fishing behaviours. Our study surveyed 154 fishers across 11 landing sites in Tanzania, followed by 15 semi‐structured interviews with key informants including fishery officers and local religious leaders. We identified key connections between religious beliefs/practices and fisher perceptions, behaviour and compliance with harvest restrictions and regulations. We demonstrate that better understanding and accounting for religious dimensions is critical for engaging with fishery stakeholders more effectively and managing global fisheries more sustainably. 相似文献
12.
Joseph R. Sara Wilmien J. Luus-Powell Susan B. Fogelson Hannes Botha Theresa C. Guillette Willem J. Smit Andre Hoffman Katlego D. Kunutu Jeremy P. Koelmel John A. Bowden 《Journal of fish diseases》2020,43(10):1185-1199
Pansteatitis is the leading cause for the decline in Nile crocodile populations and the sporadic mortality of fish in the Olifants River System, South Africa. To determine the prevalence of this disease in lentic systems, Mozambique tilapia, Oreochromis mossambicus, were collected from Lake Loskop, Lake Flag Boshielo, Phalaborwa Barrage and Lake Luphephe-Nwanedi. The former three impoundments are located within the main stem of the Olifants River, while the latter, which is geographically isolated and situated in the Limpopo River System, served as a reference site. Mesenteric adipose, liver, serosa of the swim bladder, gill and the skeletal muscle of fish sampled were examined for gross and microscopic evidence of pansteatitis. Microscopically observed changes were used to statistically compare pansteatitis prevalence between samples and sites. Based on histopathological evaluation, the adipose tissue in the liver, swim bladder serosa and coelom from severely debilitated individuals showed the most significant pathological changes. Lesions indicative of steatitis were observed in fish collected from Lake Loskop (75%), Lake Flag Boshielo (22%) and Lake Luphephe-Nwanedi (15%). Further investigation is warranted to understand the pervasiveness and mechanisms driving pathological changes of pansteatitis at Lake Flag Boshielo, Phalaborwa Barrage and Lake Luphephe-Nwanedi. 相似文献
13.
生态系统服务功能是生态系统与生态过程所形成及所维持的人类赖以生存的自然环境条件与效用,对其服务价值进行货币化评价,可以推动自然资源可持续利用,促进区域生态环境保护。以达里诺尔湖湿地为研究对象,结合达里诺尔湖湿地生态系统的结构、特征及其生态过程特点,通过资料搜集与实地调研,运用资源经济学理论和方法,对达里诺尔湖湿地生态系统服务价值进行了划分。构建了达里诺尔湖湿地生态系统服务价值评价指标体系,并对其进行了价值评价。评价结果显示达里诺尔湖湿地的服务价值为93.70×104万元,其中直接使用价值为2.19×104万元,占比为2.36%,间接使用价值为91.51×104万元,占比为97.66%。各项生态系统服务功能中以调节空气湿度价值最大,为82.76×104万元,占总服务价值的88.32%。 相似文献
14.
基于人群感知和行为视角,以福建农林大学观音湖为研究对象,通过拍照试验、访谈问卷、扫描观察收集数据,采用词频分析、照片分析、GIS技术分析,分析景观元素、景观感知以及驻留点、观景点、景点、视线廊道的空间特征,以获得游览者对滨水景观偏好特征,采用核密度分析,得到游客景观点的热点分布。结果表明,词频分析预测出游客关注湖区丰富的景观元素,以静态观赏和行进式观赏方式游览观音湖,舒适的湖区环境让游客感到心情愉悦、平静;空间角度,游览者的驻留点分布与观景点分布具有显著的一致性,表明优美的空间环境和良好的观景位置有利于游客驻留行为的产生;游览者对滨水景观的偏好是由“丰富性—功能性—特色性”三大属性特征相互协调、影响而形成的三维耦合结构模型。 相似文献
15.
以石羊河流域下游青土湖干涸湖底人工梭梭林和白刺灌丛沙包土壤为研究对象,通过分析2种植物群落5种立地条件土壤粒径分布和分形特征及其与土壤养分的关系,揭示了湖底2种典型植物群落土壤粒度的分布特征。结果表明:1)研究区固沙植被0~10 cm土壤颗粒以细砂粒为主,没有粗砂粒,其中白刺灌丛沙包表层极细砂含量、土壤颗粒物分形维数较梭梭林和对照区高。2)土壤颗粒分形维数与各粒级颗粒百分含量的关系差异较大,分形维数与黏粒、极细砂含量呈显著正相关,与细砂、中砂含量呈显著负相关,但是与粉粒含量关系不显著。土壤颗粒分形维数越大,土壤所含的细粒物质越多。3)土壤分形维数D值、黏粒、粉粒含量与有机质(SOM)、全N(TN)呈正相关性,土壤颗粒物的分形维数越大、土壤黏粒、粉粒含量越高,则土壤有机质、全N含量越高。综合分析,固定白刺灌丛表层土壤沙化程度相对较低,其他类型风蚀严重,因此,应积极采取生物措施和工程措施开展生态修复防治风蚀和盐尘暴的发生。 相似文献
16.
Shengtao FAN Tiecheng WANG Xiaolong GAO Ying YING Xue LI Yongcheng LI Yuanguo LI Jinzhu MA Heting SUN Dong CHU Yu XU Songtao YANG Qihan LI Yuwei GAO Xianzhu XIA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1143-1149
Newcastle disease virus (NDV) causes a highly contagious viral disease in poultry and
wild birds, and it can cause significant economic loss worldwide. Eight viral strains were
isolated by inoculating embryonated chicken eggs from the Poyang Lake region of China with
swab samples. All eight of the NDV isolates were identified as class I genotype 3 strains,
but they diverged notablely from class II viruses. Further analysis revealed that all
eight NDV isolates were lentogenic strains containing the
112ERQER↓L117 motif at the F protein cleavage site. The strains
were highly identical and were more species specific (chicken and waterfowl) than site
specific (Nanchang and Duchang regions). The close phylogenetic proximity of these
isolates indicates that viral transmission may happen between poultry and wild birds. Our
study demonstrates that lentogenic class I NDVs exist in clinically healthy wild waterfowl
and poultry within the Poyang Lake region. Active surveillance of these viruses to
determine their evolution and origin is one of the most realistic strategies for
preventing and controlling NDV outbreaks. 相似文献
17.
为探究多年生人工草地在青海湖流域的适应性和稳定性,本研究以青海草地早熟禾(Poa pratensis. Qinghai)和青海中华羊茅(Festuca sinensis. Qinghai)单播及混播人工草地为研究对象,分析不同种植方式下人工草地植被和土壤养分特征的变化。结果表明:青海草地早熟禾+青海中华羊茅混播草地和青海草地早熟禾单播草地的生物量和盖度高于青海中华羊茅单播草地,且在生长旺期(8月),青海草地早熟禾+青海中华羊茅混播草地生物量最高,为586.2 g·m-2;青海草地早熟禾单播、青海中华羊茅单播和青海草地早熟禾+青海中华羊茅混播草地间土壤有机质、全氮、全磷、硝态氮、铵态氮和土壤含水量在相同土壤深度下差异不显著,但土壤氮、磷及有机质间存在显著的相关性。综上所述,在青海湖流域建植青海草地早熟禾+青海中华羊茅混播型人工草地可以获得较高的产量,但需在种植和管理过程中协调好土壤氮、磷间的关系。 相似文献
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自古以“玉洱”闻名天下的洱海为云南第二大高原湖泊,面积250km^2。由于企业不达标排污、面源污染、湖滨带大面积丧失、盲目引进外来物种等原因,致使洱海水环境日益恶化,据此提出了水资源可持续利用对策。 相似文献