北票市畜牧技术推广体系改革与建设项目实施效果及建议

深化基层畜牧技术推广体系改革与建设，旨在提升基层畜牧技术推广体系公共服务能力。北票市畜牧技术推广站通过一系列措施，建立健全新型基层畜牧技术推广服务体系。基层畜牧技术推广体系改革与建设推进了体制机制创新，完善了工作机制，夯实了人才基础，提高了服务效能。通过两年的实践证明，基层畜牧技术推广体系改革与建设项目实施，有效解决了畜牧技术推广服务体系“最后一公里”问题。     

Farmers' knowledge and perception of grain legume pests and their management in the Eastern province of Kenya

Grain legumes play an important role in community livelihood and in the national economy in Kenya. Unfortunately, in many African countries, production doesn't satisfy the demand in grains due to various constrains. Understanding farmers practices and behavior in the management of grain legume pests is a crucial step in the development of sustainable management strategies. A total of 216 farmers were surveyed in eight districts of eastern Kenya to evaluate farmers' knowledge and perceptions of grain legume pests; to examine current pest management practices, and to identify other production constraints. Grain legumes are grown by a wide age-group of farmers, with both genders equally represented. Chemical control remains the main pest management strategy, and, to ensure pesticide effectiveness, farmers also use increased application rates, chemical alternation, frequent application and mixtures of chemicals. While farmers used other control measures, they showed only limited interest in biological control. The majority of the farmers had experience in grain legume farming and were able to identify the major pests, which were the legume flower thrips Megalurothrips sjostedti Trybom, the cowpea aphid Aphis craccivora Koch and the legume pod borer Maruca vitrata Fabricius. Our survey revealed that education and proximity to extension services contributed significantly to farmers' knowledge of grain legume pests, suggesting the need to provide continuous training and capacity building on integrated pest management in grain legume farming. The study also suggests integration of other pest management strategies such as the use of early maturing varieties, biopesticides and biofertilizer to reduce the use of chemical for sustainable pest management.     

Agricultural extension approach: evidence from an Integrated Soil Fertility Management Project in Ethiopia

Agricultural extension is an approach to rural development and agricultural transformation in which training, demonstration and technology transfer are key to reducing rural poverty, ensuring food security, and sustainably managing natural resources. During recent decades, different extension approaches have been tested and validated by the Ethiopian government and non-governmental organizations to stimulate participation in the agricultural extension system (AES). The most recent was a German-funded project entitled “Integrated Soil Fertility Management Project” (ISFM⁺), which employed a novel approach to piloting and upscaling proven technology and best practice. The purpose of this study was to analyze and document the modalities of ISFM⁺ and illustrate its effects on technology uptake and dissemination. The study used a mixed methods approach to collect data. ATLAS.ti and SPSS were used for data management and analysis. Farmer Research and Extension Groups and Farmer Field Schools were found to be central to the participation process. Also, the ISFM⁺ was found to aid technology transfer and helped to increase grain and residue yields as well as farmer livelihoods. Based on these empirical findings, it is argued that the ISFM⁺ approach and technology should be integrated and institutionalized in the mainstream AES in order to promote their extensive application.     

Japanese sardine (Sardinops melanostictus) mortality in relation to the winter mixed layer depth in the Kuroshio Extension region

A drastic population change in Japanese sardine (Sardinops melanostictus) has been noted as being related to winter sea surface temperature (SST) in the Kuroshio Extension region. The former studies suggest two possible explanations. One is that temperature itself affects sardine. The other is that SST represents the environmental change of the Kuroshio Extension region and other causes directly affecting sardine. In this study, we found that sardine mortality from post‐larva to age 1 negatively correlated with the winter mixed layer depth (MLD) in the Kuroshio Extension region from 1979 to 1993. During the period of a deep winter mixed layer (during the early 1980s), sardine mortality was low, whereas mortality was high when the winter mixed layer was shallow (during the late 1980s to early 1990s). By using a lower trophic‐level ecosystem model forced by the observed time series of MLD, SST, light intensity and nutrient data, we found that the estimated spring zooplankton density drastically varies from year to year and has a significant negative correlation with sardine mortality. The inter‐annual variation of spring zooplankton density is caused by the winter MLD variation. During the deep winter mixed layer years, a phytoplankton bloom occurs in spring, whereas during the shallow winter mixed layer years, the bloom occurs in winter. The results of our study suggest that the decline in the Japanese sardine population during the late 1980s to early 1990s was due to an insufficient spring food supply in the Kuroshio Extension region where sardine larvae and juvenile are transported.     

Proposal for stock-recruitment relationship for Japanese sardine <Emphasis Type="Italic">Sardinops melanostictus</Emphasis> in North-Western Pacific

ABSTRACT:   This study assessed the stock-recruitment relationship (SRR) for the Japanese sardine Sardinops melanostictus in the North-western Pacific. Of the 20 SRR models investigated, the Akaike information criterion (AIC) was the minimum (AIC = 551.2) when the data were separated into two groups (A and B) and the log-normal distribution was applied as the error term. Group A was constructed with SRR data from 1976–1987 and 1992–2004. Group B consisted of data from 1988–1991. The AIC minimum model was R  = 22.8 S  ×  e ^ε for Group A, where R , S , and ε denote the recruitment of sardine (individual number of 0-year old fish), spawning stock biomass (SSB), and error term, respectively. This model indicated that recruitment was proportional to the SSB and that no density-dependent effect operated over the range of SSB investigated (51 000–11.3 million t). Recruitment was markedly higher (lower) when the sea surface temperature (SST) of the Kuroshio Extension area in February was low (high). The essential SRR can simply be expressed as R  = 22.8 S  ×  e ^ε with the level of recruitment deviating from the model to a greater or lesser degree depending on the environmental conditions.     

水生态文明内涵及外延探究

在生态文明概念的基础上,通过共性与特性分析,探讨了水生态文明的科学内涵;从空间和时间2个不同的角度,探讨了水生态文明的外延。基于此,指出了我国水生态文明建设应当注意的问题与可供借鉴的方向。     

从"集合"的由来演化看数学哲学的基本问题

"集合"已成为现代数学的核心概念,它是人类认识事物、现象等的一种模式。迄今科学家们提出了三种重要的集合概念:Cantor集合、Fuzzy集合、Extension集合,在每一种集合上建立一种数学,集合的拓广导致了数学的拓广。     

应用可拓学原理评价黄瓜根分泌物的化感潜势

 对黄瓜组培根分泌物的化感潜势进行可拓评价, 得出黄瓜组培根分泌物对菜豆幼苗生长有显著促进作用, 而对其它3种作物有明显的毒害作用, 毒害程度为黄瓜>甜瓜>番茄。同时, 建立了黄瓜组培根分泌液的化感效应的数学模型R_E = [ k₁R_p0 / ( k₂ - k₁ ) ] ( e^{- k1t} - e^{- k2t} ) ( e- ^k1a - e^{- k2a} ) , 说明了黄瓜组培根分泌液的化感效应与组培根培养时间( t) 以及根分泌液浓度( a) 显著相关。黄瓜根分泌物对4种受体作物显示出显著的化学干扰差异, 论证了植物种内(间) 发生的干扰作用与植物的品种(系) 有关, 从理论上得出菜豆可以作为黄瓜的间套作物或下茬作物。     

国外蔬菜遗传资源的引进,研究与利用进展

１９７１～１９９６年从４０余个国家（地区）引进１４个科４８属７２种（包括变种）共１１４１０份蔬菜遗传资源,其中２０余种为国内稀有蔬菜,还有我国科研和生产急需的抗源材料、雄性不育系、耐热和耐低温等珍贵材料。根据我国不同地区的生态气候类型,与地方科研、生产单位结合对引进的５３４５份材料共同试种鉴定,筛选出４０余个优良品种在生产上直接推广利用,获得了巨大的经济效益。选出的品种中有７个通过了省（市）品种审（认）定,共推广面积２６１ｋｈｍ２。大批引进的蔬菜优异资源被全国育种单位广泛用于培育新品种,获得了重大的社会效益和经济效益。