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101.
  1. Devil rays (Mobula spp.) are globally threatened cartilaginous fishes that have attracted global conservation concern owing to their high extinction risk and lack of protection in many countries. Limited resources and data on threatened marine species, including devil rays, impede conservation actions, particularly in developing countries, many of which have high biodiversity.
  2. Devil ray catch is a component of artisanal fisheries in Bangladesh, but data on their fisheries and trade are limited. To characterize devil ray fishing practices, fishers’ perception and trade, 230 fishers and traders were interviewed between 4 June 2018 and 22 June 2019, in four areas of south-east Bangladesh. Catch data were also opportunistically collected at landing sites.
  3. Six devil ray species were documented, caught in an array of gill nets, set-bag nets and longlines. All interviewed fishers reported life-long devil ray bycatch in some numbers, and also noted a decline in catch over the last decade. Bottom trawling, increased bycatch levels, increased demand for devil ray products and, in some cases, ecosystem changes were identified by fishers as threats to devil ray populations.
  4. Unregulated and undocumented trade and retained bycatch, especially by gill nets and set-bag nets, are fuelled by local consumption of devil ray meat and international trade in meat and gill rakers. Compliance with international trade control treaties for all Mobula spp. or the Bangladeshi law protecting Mobula mobular was low, with the majority of fishers (87%, n = 174) unaware of their existence.
  5. To manage devil ray fisheries, and prevent possible population declines, we propose a combination of legally enforced gear modifications, and catch and trade control through community-owned implementation strategies. Additionally, we propose the simultaneous implementation of inclusive, community-based awareness and stewardship projects in conjunction with a coast-wide ray monitoring programme. Finally, we emphasize that more research and action rooted in a sustainable fishery model is urgently needed to protect Bangladeshi devil ray populations.
  相似文献   
102.

Shrimp farming is fundamental to the national economy of Bangladesh, particularly through earning foreign currency. The nationwide lockdown and international cargo restriction jeopardized the sector and breaking its marketing chain. Assessing the degree of farming socio-economic peril from COVID-19 and suggesting early coping strategies and long-term mitigation measures are pressing to build resilience for this food production sector. To collect survey data, two key-informant face-to-face surveys with 51 shrimp farmers and 62 consumers in southwest Bangladesh were accomplished. As national lockdowns restricted access to export markets and movements within the country, farm incomes decreased against rising production costs. To compensate, farmers reduced their workforce (29.4%), but even with the sale of co-cultured finfish still suffered from large drops in revenue (42.8% average profit reduction). Furthermore, we present evidence that shrimp farmers should consider diversification of aquaculture product type as co-culture of additional shrimp species was a poor mitigation strategy against large market price fluctuations. Product price reductions were passed on to the consumer, who enjoyed falling product prices including more expensive shrimp products, but the markup for nearly all aquaculture products increased. The current jeopardy and consequences of shrimp farming future are discussed, including coping strategies to help policymakers in building resilience against future uncertainties.

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103.
The golden jackal is perceived by farmers in Bangladesh as a primary pest of agricultural crops and domestic livestock. Very few farmers take any actions to reduce jackal attack on crops or livestock other than guarding their fields at night during the ripening crop stages. Rarely have the role and importance of the jackal as a small mammal predator in the agroecosystem in Bangladesh been studied. Until studies are completed to clarify these issues, lethal methods of jackal management should not be attempted.  相似文献   
104.
孟加拉杂交水稻研究概况   总被引:2,自引:0,他引:2  
廖伏明 《杂交水稻》1997,12(6):26-27
孟加拉杂交水稻研究概况*HybridriceresearchinBangladeshA.W.Julfiquar,M.MohiulHaque,A.K.G.M.EnamulHaque,M.AlamgirHosain(孟加拉水稻研究所Gazipur1701...  相似文献   
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106.
This study reports the effects of shifting cultivation at slashing stage on soil physicochemical properties at Bandarban Sadar Upazila in Chittagong Hill Tracts of Bangladesh. At this initial stage of ...  相似文献   
107.
在孟加拉国吉大港山区选择两块研究地,研究轮换种植对土壤中真菌和细菌群落的影响。两块研究地均包含轮换种植和本地社区管理的乡村森林,第一块研究地点选择在兰加马蒂地区,第二块研究地点选择在吉大港的班多尔班地区。在两个地点和不同用途的地块中,其表面土(0-10cm)和地表下土(10-20cm)的土壤质地不同,分别为砂壤和粘土。轮作地的土壤pH和含水量比乡村森林的低。研究结果表明:在兰加马蒂和班多尔班地区,大多数情况下,轮作地的表面土和地表下土壤中的真菌和细菌群落数量比乡村森林的低。在兰加马蒂和班多尔班地区的轮作地中,炭疽菌属(CoHetrotrichum)和镰孢菌属(Fusarium)真菌稀少,而两个地方的不同用途地块中均有细菌球菌属(Coccus),芽孢杆菌属(Bacillus)和链球菌属(Streptococcus)。在两个地方的不同用途地块中常见的真菌有曲霉属(Aspergillus)、根霉属(Rhizopus)、木霉属(Trichoderma)和青霉菌属(Penicillium)。在其它的土壤区系中,由于轮换种植导致土壤环境退化的程度还需要进一步的研究。  相似文献   
108.
为了调查不同土地植被覆盖对水质量的影响,在孟加拉吉大港山区兰加马蒂的三个地区(Manikchari,Ghagra和Muralipara)对小溪和渗透水采集流动水样,进行化学分析。结果表明,在Manikchari地区,与自然植被和人工林混交植被相比,在成熟和幼年的石梓(Gmelina arborea)人工林植被流动的溪流水样中,SO2-、Ca2+的浓度和pH值较高 (p<0.05),Na+浓度较低。在Ghagra地区,与衰退的自然植被中的水域中采集的水样比较,在8年生的柚木(Tectona grandis)人工林水域流动的溪流水样中,有明显高浓度SO42-和K+、高传导率和高总溶解固体物,但HCO3-、NO3-和PO43-浓度明显较低。在Muralipara地区,与轮作地的渗透水中采集的水样相比,在自然植被和耕地混交地中采集的流动的溪流水样中,有明显高浓度的HCO3-、NO3-、Na-、k-、Ca2+和Mg2+,同时,其电导率和总溶解固体量也明显高于渗透水和轮作耕地管井水。表2参13。  相似文献   
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