南京市观光农业发展现状及潜力调查

通过对观光农业游客的调查,分析了南京市观光农业的发展现状及潜力.调查发现,参加农业观光旅游的游客呈现出年轻化且收入水平不高的主要特征,而影响消费者参与的主要因素是交通等配套设施的不完善及旅游项目的单一化等问题.提出了增加产品的差别化、加强有效宣传力度、突破重点消费群体的政策建议.     

E-commerce development in rural and remote areas of BRICS countries

E-commerce plays an essential role in modern trade today. It is expected that e-commerce volume amounted to 29 trillion USD in the world in 2017, and would grow with the spread of the Internet and information and communication technologies(ICTs). Brazil, Russia, India, China and South Africa(BRICS), together with many others, consider e-commerce a means to facilitate rapid, inclusive and sustainable economic growth, improving the living standards and alleviating poverty. This article examines areas for potential cooperation by BRICS countries in e-commerce development across rural and remote areas to fight poverty. It analyses the current state of e-commerce development in rural and remote areas in each of the BRICS countries, including cases of public and private initiatives to support it. The article also defines the opportunities which e-commerce brings to people living in rural and remote areas. Moreover, it evaluates the existing challenges and risks. The article concludes that despite the rapid e-commerce development in BRICS countries, and significant opportunities created, there are still issues of disproportionate e-commerce in varied regions and the lack of BRICS cooperation in this sphere. Based on a comparative and normative in-depth, systematic analysis, the article develops a set of recommendations for deepening BRICS countries' cooperation in the following areas: infrastructure in rural and remote regions; education; consumer protection; online dispute resolution; coordinated policy in the international scene, including representation of BRICS countries in international indexes, such as the Organization of Economic Co-operation and Development(OECD) Digital Services Trade Restrictiveness Index(STRI).     

Research on an International Marketing Strategy for Japanese Rice

This study aims to clarify the factors that form rice prices for different producing areas and brands in Japan, while ascertaining consumers＇ criteria in purchasing rice and their preference for taste in China, in order to establish the method to formulate an overseas marketing strategy for Japanese rice.     

Taste preferences in fishes

The fish gustatory system provides the final sensory evaluation in the feeding process. Unlike other vertebrates, the gustatory system in fish may be divided into two distinct subsystems, oral and extraoral, both of them mediating behavioural responses to food items brought in contact with the fish. The abundance of taste buds is another peculiarity of the fish gustatory system. For many years, morphological and electrophysiological techniques dominated the studies of the fish gustatory system, and systematic investigations of fish taste preferences have only been performed during the last 10 years. In the present review, basic principles in the taste preferences of fish are formulated. Categories or types of taste substances are defined in accordance with their effects on fish feeding behaviour and further mediation by the oral or extraoral taste systems (incitants, suppressants, stimulants, deterrents, enhancers and indifferent substances). Information on taste preferences to different types of substances including classical taste substances, free amino acids, betaine, nucleotides, nucleosides, amines, sugars and other hydrocarbons, organic acids, alcohols and aldehydes, and their mixtures, is summarised. The threshold concentrations for taste substances are discussed, and the relationship between fish taste preferences with fish systematic position and fish ecology is evaluated. Fish taste preferences are highly species‐specific, and the differences among fish species are apparent when comparing the width and composition of spectra for both the stimulants and the deterrents. What is evident is that there is a strong similarity in the taste preferences between geographically isolated fish populations of the same species, and that taste preferences are similar in males and females, although at the individual level, it may vary dramatically among conspecifics. What is noteworthy is that taste responses are more stable and invariable for highly palatable substances than for substances with a low level of palatability. Taste preferences as a function of pH is analysed. There is a good correspondence between development of the gustatory system in fish ontogeny and its ability to discriminate taste properties of food items. There is also a correspondence between oral and extraoral taste preferences for a given species; however, there is no correlation between smell and taste preferences. Taste preferences in fish show low plasticity (in relation to the diet), appear to be determined genetically and seem to be patroclinous. Fish feeding motivation and various environmental factors like water temperature and pollutants such as heavy metals and low pH water may shift fish taste preferences. Comparisons between bioassay and electrophysiological data show that palatability is not synonymous with excitability in the gustatory system. The chemical nature of stimulants and deterrents in various hydrobionts is outlined. The significance of basic knowledge in fish taste preferences for aquaculture and fisheries is emphasised.     

Range and diet of Eurasian otters Lutra lutra (L.) in the catchment of the River Lee (south‐east England) since re‐introduction

• 1. After re‐introduction in 1991 of Eurasian otters Lutra lutra (L.) to the River Lee catchment (England), changes in range were assessed from spraint collections in the periods 1991–1994, 1995–1997 and 1998–2000. Diet, assessed from concerted spraint sampling within the first two periods, was compared between 1992–1994 and 1996–1997, with dietary preferences assessed for the initial phase using available fish stock data for that period.
• 2. In 1991–1994, range encompassed much of the catchment, but reduced in 1995–1997 to a small area around the initial release site, when the otters were joined/replaced by natural immigrants presumed to come from a contiguous catchment. Range expanded in 1998–2000 to upper reaches of the catchment's major tributaries.
• 3. Fish, mainly cyprinids, were the major prey taken in 1992–1994 and 1996–1997. In 1996–1997, fish abundant near the initial release site became more prominent, in particular chub Leuciscus cephalus, and (upstream) species characteristic of the initial range decreased in importance.
• 4. Despite confirmed and unconfirmed sightings of females with cubs, it remains unclear whether the presence and apparent expansion of otters in the Lee catchment is the result of the re‐introduction or of natural immigration/recolonization.

Copyright © 2003 John Wiley & Sons, Ltd.     

Diel variation in stream fish habitat suitability criteria: implications for instream flow assessment

• 1. Habitat suitability criteria that fail to incorporate temporal variability in habitat preferences of stream fish may mis‐represent critical habitat requirements and lead to setting of inappropriate flow targets when used in instream flow assessments. Developing suitability criteria from daytime observations alone relies on the assumption that habitat preferences are constant over the diel cycle. Few studies have tested these assumptions, particularly for small‐bodied, cryptic, benthic species.
• 2. During summer in two gravel‐bed rivers, bluegill bullies (Gobiomorphus hubbsi), torrentfish (Cheimarrichthys fosteri) and upland bullies (Gobiomorphus breviceps) exhibited strong preferences with respect to water depth, velocity and substratum size. All three species underwent a diel shift in microhabitat preference for at least two of these variables.
• 3. Microhabitat preferences were generally weaker when fish were active at night; bluegill bullies, upland bullies and especially torrentfish were observed over a broader range of depths, velocities and substratum sizes at night than during the day. Observations of fish in a stream simulator confirmed that bluegill bullies and torrentfish showed a preference for runs at dusk and return to riffles before dawn, but habitat preferences of upland bullies remained static across the diel cycle.
• 4. Diel microhabitat shifts affected the assessment of flow requirements. Instream habitat analysis of the Waipara River using separate day and night suitability criteria predicted differing amounts of habitat available at a given flow, and the relationships between fish abundance, fish density and flow. The presence of diel microhabitat shifts in stream fishes suggests that instream habitat analyses will produce more effective and defensible flow recommendations when patterns of nocturnal microhabitat preferences are known and critical habitat bottlenecks can be identified. Copyright © 2011 John Wiley & Sons, Ltd.

     

Migration and behavior of juvenile North Pacific albacore (Thunnus alalunga)

Archival tags were used to study the seasonal movements, migration patterns and vertical distribution of juvenile North Pacific albacore (Thunnus alalunga). Between 2001 and 2006, archival tags were deployed in North Pacific albacore in two regions of the Northeast Pacific: (i) off Northern Baja California, Mexico and Southern California, and (ii) off Washington and Oregon. Twenty archival tagged fish were recovered with times at liberty ranging from 63 to 697 days. Tagged albacore exhibited five distinct, seasonal migratory patterns. Depth and temperature data also showed a broad range of vertical behaviors. In certain regions such as off Baja California, Mexico, juvenile albacore make frequent dives to depths exceeding 200 m during the day and remain in the surface mixed layer at night, whereas off Oregon and Washington they remain near the surface both day and night. Water temperatures encountered ranged from 3.3 to 22.7°C. Peritoneal temperatures were significantly higher by an average of approximately 4°C, as expected in these warm‐bodied fish. This study provides a comprehensive examination of horizontal and vertical movements of juvenile albacore in the Northeast Pacific. The results reveal diverse behavior that varies regionally and seasonally as albacore move among different habitats throughout the entire North Pacific.     

基于不同年龄段消费者的黄大茶偏好研究

采用9点喜好度标度（9-point hedonic scale）和5点正好标度（Just about right,JAR）分别对不同年龄段消费者进行黄大茶喜好度检验及感官属性的接受度评价。结果表明,年轻消费者和中年消费者喜好比较接近,更偏爱具有甜香和甘醇味的低焙火和高嫩度黄大茶;老年消费者更偏爱具有焦火香、苦涩味、糊味的高焙火和低嫩度黄大茶。进而采用惩罚分析将喜好度数据与JAR数据联系起来,定性地得出3个年龄段对样品整体喜好度最有影响的属性、属性优化方向及改进优次顺序,为针对性地设计和加工黄大茶产品提供一定的参考。     

Stated preferences of llama keeping functions in Bolivia

Bolivia accounts for approximately 63% of the South American llama population. Llamas keep playing an important role in the subsistence of smallholdings in the Andean regions fulfilling various functions in the productive, social and cultural life of the people. The present study evaluates functions of llama keeping as a prerequisite to the formulation of a community-driven breeding programme. A ranking approach was applied with 75 farmers in 6 villages. Sampling considered the factors gender and central versus remote communities. The different functions were presented visually. Each farmer was asked to arrange the illustrations according to his preference order. In total, 10 functions were suggested, covering the categories transport, sale or use of products, integration of animals in cultural events and herd size as capital asset. Ranking frequencies of stated preferences were calculated. A rank-based t-test was applied for multiple pair-wise comparisons within ranking groups gender and community provenance, respectively. Between-group comparison was performed by non-parametric Wilcoxon rank-sum test. The capital function was most important (14.6% of total ranking frequency) followed by the transport function to cultivated areas (13.7%) and the transport function for other purposes in third place (10.8%). All pair-wise comparison analysis indicated a significant difference for the two highest ranked functions. Functions ranked from 3rd to 9th position showed poor separation due to similar means with high variance. Bottom ranked function with significant separation for all ranking groups was the ‘Integration of animals in cultural events or rituals’. Women appreciated the dung of the animals more than men (p = 0.0376), whereas men put higher value on the sale of live animals for cash generation in case of emergency (p = 0.0006) and for cash availability (p = 0.0371). It is concluded that traditionally important functions of llamas like wealth accumulation and the close integration of the animals in mixed farming systems prevail. Breeding policies and breeding decisions will be more suitable when taking into account farmers' preferences and gender-specific perceptions.     

Litter N-content influences soil millipede abundance,species richness and feeding preferences in a semi-evergreen dry forest of Guadeloupe (Lesser Antilles)

Despite the impact of soil millipedes on litter fragmentation in tropical forests, there have been few studies dealing with factors determining their habitat preference in these ecosystems. In a natural secondary dry forest of Guadeloupe on Leptosol, two complementary studies were carried out in order to test the hypothesis that litter N-content strongly influences millipede distribution. Millipede abundance and species richness were described in the field under two tree species, Bursera simaruba and Pisonia subcordata, and were related to the chemical characteristics of their foliage. In addition, a laboratory experiment was done in order to assess millipede feeding preferences regarding the chemical characteristics of leaves from various species. Millipede abundance and species richness were significantly higher under P. subcordata than under B. simaruba, probably due to the higher N content of P. subcordata leaves. Moreover, millipedes fed preferentially on N-rich leaves. The present study confirms that there was a close correlation between the preferred food, its chemical composition and the local distribution of millipede populations.