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This paper examined climate change adaptation strategies in fish farming and the effect of such methods on the profit of fish farmers in the Niger Delta region of Nigeria, Africa’s most populous country. Using cross‐sectional data obtained from 420 fish farmers from the region and applying multivariate probit and instrumental variable regressions, the study found that fish farmers have adopted a broad range of strategies to address climate risk and that these have significantly increased farmers’ profit. Our findings indicated important relationships between certain farm, socio‐economic and institutional characteristics and the adaptation actions. The study provides useful insight into factors that potentially encourage the adoption of livelihood‐enhancing climate risk adaptation strategies by fish farmers in the Niger Delta region and similar contexts.  相似文献   
2.
我国淡水鱼流通组织模式评价与选择   总被引:1,自引:0,他引:1  
结合实地调查,按组织化程度高低把我国淡水鱼流通组织模式分成了企业产运销一体化型、市场交易型和联盟合作型三种类型,并从质量保障能力、数量保障能力、成本竞争优势、快速供应市场能力、节能减排优势五个方面对各模式进行了评价,最后提出了针对大宗淡水鱼、特优淡水鱼以及品牌化淡水鱼流通的组织模式选择策略。  相似文献   
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文章简要介绍了山西天镇晚白垩世恐龙化石的发现、发掘概况及动物群的特征,讨论了含化石地层—灰泉堡组的时代,认为无疑应属晚白垩世。以晚白垩世蜥脚类巨龙科和鸟臀类甲龙科化石为代表,别具特色的新恐龙动物群为一突破性的发现,对它的深入研究,将对蜥脚类、甲龙类及其共生动物群的组成、性质、演化、迁徙和动物地理区的划分及探讨白垩纪末恐龙的绝灭有重要的科学意义。  相似文献   
5.
我国南方草地资源丰富,发展草业潜力极大。本文就南方草地的现状、类型及发展草业的途径进行了探讨。  相似文献   
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Aquaculture growth has led to worries about overfishing and reduction in wild‐caught food fish supply because of increased demand for fish meal. As such, the price ratio between fish meal and soybean meal has received much attention as an indicator of changing market conditions. In recent years, the price ratio between these two commodities has become more volatile. Several authors have suggested that the traditional relationship between fish meal and soybean meal has broken down and that this is evidence of increased demand pressure on fish meal. In this article, we investigate the hypothesis that there are two regimes for the relative price between fish meal and soybean meal. The empirical results support this hypothesis, with the low‐price regime representing the traditional stable relative price. The continued linkages between the fish meal and the soybean meal markets indicate that aquaculture is reducing its dependency on marine proteins in favour of vegetable proteins.  相似文献   
7.
In Japan, some fishery cooperative associations use their fishery harbor names as a brand to differentiate their own shore fish. Most notable is the branding of mackerel. In this paper, we analyze the effects of branding using a discrete/continuous model. The results are as follows. First, there is first-mover advantage in the branding of mackerel. For instance, unlike other brands of mackerel, Seki-saba as the pioneering brand can increase its brand equity. Second, other brands have opposing effects that increase and decrease the brand equity of the pioneering brand. We find the former is strongest in the early stages of fishery branding when there are few competing brands of mackerel, while the latter becomes stronger in later stages when many other brands emerge.  相似文献   
8.
云山共有脊椎动物66科211种,具有资源丰富、过渡性强、珍稀动物多和开发价值高等特点;提出了动物资源的保护利用对策。  相似文献   
9.
发展网箱养鱼 致富库区农民   总被引:2,自引:0,他引:2  
本文介绍了山东省枣庄市发展网箱养鱼,致富库区农民的经验,并着重阐述了科技推广应用、社会化服务和加强组织领导对发展网箱养鱼的意义和作用。  相似文献   
10.
本文采用超高效液相色谱串联质谱法测定了腌鱼中氟虫腈及其代谢物氟虫腈砜、氟虫腈亚砜、氟甲腈。腌鱼样品经乙腈提取、盐析和吸附剂净化,以0.1%甲酸的甲醇溶液和0.1%甲酸的5 mmoL·L-1乙酸铵溶液为淋洗液在BEH C18色谱柱梯度洗脱,电喷雾负离子多反应监测(Multiple Reaction Monitoring,MRM)模式检测。结果表明,氟虫腈及其代谢物在0.25~10.0 ng·mL-1呈良好的线性关系,相关系数均大于0.999;在1.0~10.0μg·kg-1添加范围内,氟虫腈及其代谢物的回收率为91.79%~109.84%,相对标准偏差为0.91%~3.39%(n=6);该方法检出限和定量限分别为0.2~0.4μg·kg-1和0.8~1.2μg·kg-1。本方法操作简单、灵敏,可同时测定腌鱼中氟虫腈及其代谢物的残留量,为其日常监管提供技术参考。  相似文献   
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