稻鱼共生系统的土壤产甲烷和甲烷氧化微生物群落

稻鱼共生对稻田甲烷(CH₄)排放产生明显影响，但稻鱼共生是否影响与CH₄排放相关的产甲烷菌和甲烷氧化菌仍有待阐明。本研究以全球重要农业文化遗产——青田稻鱼系统为例，通过田间试验，比较研究了水稻单作系统(RM)、无饲料投放的稻鱼共生系统(RFN)和有饲料投放的稻鱼共生系统(RFF)水稻和田鱼的产量、土壤碳氮磷含量以及产甲烷和甲烷氧化微生物的特征。结果表明，RFF的水稻产量和土壤碳氮增量均显著高于RM。荧光定量PCR分析表明，稻鱼共生(RFN和RFF)的产甲烷菌和甲烷氧化菌丰度显著高于RM,且RFF的产甲烷菌丰度显著高于RFN。Illumina Miseq测序分析表明，稻鱼共生显著影响产甲烷菌群落结构，但对甲烷氧化菌群落结构的影响不显著；对于不同代谢类型的产甲烷菌，稻鱼共生(RFN和RFF)氢营养型产甲烷菌的丰度显著高于RM,且RFF的乙酸营养型产甲烷菌丰度显著高于RFN;对于不同代谢类型的甲烷氧化菌，RFN和RFF对类型Ⅰ的甲烷氧化菌丰度影响均不显著；RFF中类型Ⅱ的甲烷氧化菌丰度显著高于RM和RFN。可见，稻鱼共生可明显影响产甲烷菌和甲烷氧化...     

我国稻田养鱼的新进展

稻田养鱼有两种形式,即“稻鱼共生”和“稻鱼轮作”。稻鱼共生系指水稻和鱼群共同生活在稻田中,双方彼得到一定利益。这种稻田养鱼方式以培育吃草的鱼种为主,搭养当地需要的鱼种为辅。稻鱼轮作是指水稻与养鱼轮流生产,即一年当中只种一季水稻,余时则为养鱼。如利用冬闲田、固水田及湖区的低洼田水稻收获后即行养鱼,此种方式以养食用鱼或大规格(15厘米以上)鱼种为主。       

封面说明

<正>封面图片由浙江省青田县农业局吴敏芳于2014年8月24日摄于浙江省青田县仁庄镇浙江大学"青田稻田养鱼系统"试验基地(28°02'N,120°14'E).青田县位于浙江省东南部,瓯江中下游,属亚热带季风气候,全县稻田面积6200 hm~2,其中85%为稻田养鱼模式.在中国具有千年历史的稻鱼共生系统是农业利用种间互惠的典范,被联合国粮农组织选入世界首批重要农业文化遗产.浙江大学生态研究所农业生态研究团队通过多年的研究揭示了水稻和田鱼之间的互惠是稻鱼共生系统     

稻鱼鸭复合生态经济效益的初步研究

试验表明．稻鱼鸭种养共生,水稻增产 １０％以上,同时增收鲜鱼 １０３６．５ ｋｇ· ｈｍ－２,成鸭２３８．９～４８９．３ ｋｇ·ｈｍ－２;水稻土壤全Ｎ、Ｐ、Ｋ和有机质含量分别增加２７．９、 ４４． ３、６． ５和 ２８． ２％,提高了土壤肥力;水稻植株虫口量最少．稻鱼鸭共生大大提高了稻田 的产出和效益．属良性循环的高效复合生态农业．     

“双季稻-鸭”共生生态系统稻季磷循环

稻鸭共生是对中国传统农业稻田养鸭的继承与发展。在长江流域双季稻主产区湖南布置了稻田养鸭田间对比试验,以常规稻作为对照,采用投入产出法,分析"稻鸭共生"生态系统P的输入输出及循环情况。结果表明:"早稻-鸭"共生生态系统P输出为52.28kg·hm-2,其中鸭产品P为1.71kg·hm-2;"晚稻-鸭"共生生态系统P输出为83.24kg·hm-2,其中鸭产品P为6.17kg·hm-2;在早、晚稻两季,"稻鸭共生"系统在目前的P养分投入水平下,降低了土壤P的亏缺量;鸭子系统P输入主要来自系统外投入的饲料P;鸭粪P在系统内循环利用,两季循环率分别为12.5%和13.5%;两季稻作后,"稻鸭共生"土壤截存的P量为195.41kg·hm-2,比常规稻作显著提高了36.9%;"稻鸭共生"可对稻田土壤增加鸭粪P为17.75kg·hm-2。     

"稻鸭共生"生态系统稻季N、P循环

稻鸭共生是对我国传统农业稻田养鸭的继承与发展。在长江流域双季稻主产区湖南布置了稻田养鸭田间试验,以常规稻作为对照,研究"稻鸭共生"生态系统N、P循环。结果表明:"稻鸭共生"生态系统N、P输出分别为153.50 kg/hm²和59.03 kg/hm²,其中鸭产品N、P输出分别是23.98 kg/hm²和3.10 kg/hm²;"稻鸭共生"系统在目前的N、P养分投入水平下,土壤存在严重的N和P亏缺;鸭子系统N、P输入对系统外饲料投入依赖高,自持能力较差;鸭粪N、P参与当季的稻田养分循环,其循环率分别为10.66%和28.16%。     

红萍钾在稻萍鱼共生系中循环利用研究

本文应用示踪技术研究红萍钾在稻萍鱼共生系中的运转和利用情况。通过实验,定量地阐述了红萍钾在各养分库间的运转途径和运转量,并分析稻、鱼对红萍钾利用率不高的内在原因及其解决途径。同时拟定出红萍钾在该系统内循环运转和平衡模式。     

基于碳足迹的传统农业系统环境影响评价——以青田稻鱼共生系统为例

现代农业在带来粮食高产的同时也产生许多生态环境问题,这促使人们再次把目光转向传统农业系统。一些传统农业系统不仅具有突出的经济、社会和文化价值,还具有多种重要的生态功能,如温室气体减排。然而,已有研究缺乏对传统农业系统整个生命周期的固碳减排能力的测算及其环境影响的评价。为此,基于农户调研数据,运用生命周期评价法对青田稻鱼共生系统的碳足迹进行了测算,并与当地水稻单作系统进行比较。研究发现:(1)青田稻鱼共生系统和水稻单作系统碳足迹分别为6266.7 kgCO_2-eq/hm~2和7520.0 kgCO_2-eq/hm~2,单位产值碳足迹分别为0.12 kgCO_2-eq/元和0.21 kgCO_2-eq/元。与水稻单作系统相比,稻鱼共生系统排放的温室气体更少,环境影响更小,生态和经济效益更高。(2)农业生产过程中积累的CH_4是碳足迹的最主要来源,农业生产资料投入中的化肥是碳足迹的的第二大来源。农业生产资料投入中的饲料则是稻鱼共生系统碳足迹的另一重要来源。通过碳足迹的方法对青田稻鱼共生系统的环境影响进行量化,不仅丰富了碳足迹在实际应用中的适用类型,对于其他传统农业系统的环境影响评价也具有借鉴意义。     

侗族地区“稻鱼鸭”复合系统是具有重要意义的农业文化遗产

我国传统稻鱼共生系统已被联合国粮农组织列为首批五个全球重要农业文化遗产保护试点之一。我国侗族地区广泛实行的”稻鱼鸭”复合耕作系统历史悠久、内涵丰富、效益显著,同样具有重要的保护价值,应当受到人们的重视。     

体验“刀耕火种”

农业文化遗产的概念源自联合国粮农组织2002年启动的“全球重要农业文化遗产”项目。目前,此项目已经在全球选出了5个试点系统,包括中国浙江青田的稻鱼共生系统。另外,贵州从江的稻鱼（鸭）复合系统、江西万年的稻作起源与贡米生产和云南红河州的哈尼梯田也正在申请成为全球重要农业文化遗产保护试点。     

稻—鱼—蛙立体农业生态效益的研究

我国是一个稻米生产大国 ,古代劳动人民早已认识到稻田中的鱼、蛙与水稻生长的互利关系。三国时代就有稻田养鱼的记载 :“郫县子鱼黄鳞赤尾 ,出稻田可以作酱”;宋朝诗人辛弃疾的词句 :“稻花香里说丰年 ,听取蛙声一片”,生动地描述了那种自然景象。但是到目前为止 ,对稻 -鱼 -蛙共生生态系统的系统研究还较缺乏。本文旨在通过在稻田中放养美国青蛙及草鱼 ,进行立体种养殖来分析探讨稻 -鱼 -蛙立体农业的生态效益 ,为该项技术的深入研究、生产的推广普及提供一些理论依据。放草鱼夏花 2 0 0尾 ,进行经济效益的比较试验。1 .3　秧苗的栽插与鱼…     

稻鱼系统中田鱼对资源的利用及对水稻生长的影响

稻田为鱼类等水产生物提供生境,稻田养鱼在提高水稻产量的同时,通过控制病虫害的暴发以及充分利用养分来降低化肥农药的使用.但田鱼对稻田资源的摄食(浮游植物、杂草、浮萍、田螺)及利用后转化成养分对水稻生长发育的促进作用尚缺乏研究.本研究设计了2个田间试验,通过摄像观察稻鱼系统中田鱼的活动,采用稳定性同位素分析田鱼对稻田资源的摄食,并测定水稻的生长发育进程和水稻产量.结果表明: 与鱼单养处理相比,稻田养鱼显著地促进了田鱼的活动频率并扩大了田鱼的活动范围.在稻鱼共作不投喂饲料处理下,稻田中3类水生生物(浮萍、浮游植物、田螺)对田鱼食谱的贡献率分别为22.7%、34.8%和30.0%;而投喂饲料处理下,这3种水生生物对田鱼食谱的贡献率分别为8.9%、5.9% 和1.6%,饲料的贡献率为71.0%.与水稻单作比较,稻鱼共作处理显著增加水稻分蘖期和灌浆期的叶片氮含量,延长分蘖期10~12 d,并显著提高成穗率和产量.表明稻鱼系统通过田鱼摄食稻田资源并转化为水稻可利用养分,促进了水稻生长,实现了水稻产量的提升.     

稻—萍—鱼系统中红萍氮素吸收利用及有效性研究

本文报道以红萍为饵料,鱼类对红萍氮素消化吸收、转化情况。试验结果表明:草鱼和尼罗罗非鱼对红萍氮素的消化和吸收率约为60％,其中30％红萍氮素转化为鱼体动物蛋白,另外约30％氮素排出体外。在田间条件下,尼罗罗非鱼摄食红萍,每季平均增长率约为41—40％。稻田养鱼,以萍喂鱼,鱼粪肥田,萍体氮素得以吸收利用,效益明显。在稻萍鱼体系中,当季红萍氮素的总利用率可达45—50％,而红萍单作肥料处理其利用率仅为30—36％,第二季作物对红萍残留氮素回收率可达7.83—9.64％,比红萍单作肥料处理高3.33—4.11％。第二季残效明显优于红萍压施处理,晚季稻谷产量的增产率可达13—25％,比压施红萍作肥料处理高7—8％。     

Long-term impact of pulses crop rotation on soil fungal diversity in aerobic and wetland rice cultivation

Pulse crop rotation in rice cultivation is a widely accepted agronomic practice. Depending upon the water regime, rice cultivation has been classified into wetland and aerobic practices. However, no studies have been conducted so far to understand the impact of pulse crop rotation and rice mono-cropping on fungal diversity, particularly in aerobic soil. A targeted metagenomic study was conducted to compare the effects of crop rotations (rice-rice and rice-pulse) on fungal diversity in wetland and aerobic rice soils. Out of 445 OTUs, 41.80% was unknown and 58.20% were assigned to six phyla, namely Ascomycota (56.57%), Basidiomycota (1.32%), Zygomycota (0.22%), Chytridiomycota (0.04%), Glomeromycota (0.03%), and Blastocladiomycota (0.02%). Functional trait analysis found wetland rice-pulse rotation increased symbiotrophs (36.7%) and saprotrophs (62.1%) population, whereas higher pathotrophs were found in aerobic rice–rice (62.8%) and rice-pulse (61.4%) cropping system. Certain soil nutrients played a major role in shaping the fungal community; Ca had significant (p < 0.05) positive impact on saprotroph, symbiotroph and endophytes, whereas Cu had significant (p < 0.05) negative impact on pathotrophs. This study showed that rice-pulse crop rotation could enhance the saprophytic and symbiotic fungal diversity in wetland and reduce the population of pathogens in aerobic rice cultivation.     

Rice–fish culture: an option for smallholder Sawah rice farmers of the West African lowlands

The introduction of Asian-based Sawah¹ farming system through an ecotechnology approach has opened a new frontier for diversification of the rice-based cropping system in West Africa. On-farm rice–fish culture experiments were conducted at Biemso under irrigated Sawah and Nobewam irrigation project sites in Ashanti region, Ghana, during the main cropping season of 2000. The objectives of the study were to evaluate the effect of fish on performance of rice and to assess relative economics of concurrent rice–fish culture and rice monoculture under lowland. The results indicated that the presence of fish did not significantly depress the yield of rice. The size of the fish increased from an initial weight of 25–80 g at Nobewam and to 90 g at Biemso site during the culture period of 100 and 120 days, respectively. The net return from the rice–fish culture ranged from US$ 1106.90 to 1233.80 whilst that of rice monoculture ranged from US$ 1046.40 to 11108.60. Percentage increase in revenue from the rice–fish system over the rice monoculture ranged between 5 and 11%. These results suggest that rice–fish integration could be a viable option for diversification for smallholder rice farmers in lowlands with soil and water conservation structures and reliable source of water for irrigation.     

An assessment of fish species assemblages in rice fields in West Bengal,India: implications for management

Wetlands such as rice fields and associated canals are congenial habitats for different fishes and provide the foundation of rice‐fish culture. The selection of suitable fish species determines the success for this linkage of aquaculture and agriculture. An assessment of fish assemblages in selected rice fields and associated canals in West Bengal, India documented the candidate species for culture and conservation in rice fields. Indigenous minnow traps made of bamboo were employed in the rice fields and canals for a period of 3 months, to collect and record the fish abundance. A total of 531 fishes representing 19 different species were caught from the rice fields in 30 sampling efforts. From the canals, 13 different fish species totaling 676 fishes were collected in 80 sampling efforts. The fish collected per trap in the rice fields (mean 17.7 ± 1.97 SE) remained significantly different (t = 4.461, df = 112; P < 0.001) from those of the canals (mean 8.05 ± 1.09 SE). Diversity indices ranged between 1.91 and 2.01, with a 53% similarity between the rice fields and canals. Among the fish species collected, Badis badis, Colisa fasciatus and C. lalia exhibited high abundance; the two species Heteropneustes fossilis and Mystus vittatus established as threatened fish categories, showed low abundance. The fish species collected were important as food resources and the ornamental fish trade, and many of them bear potential in regulating mosquitoes in the rice fields. These fish assemblages in the rice fields and associated canals suggest a rice‐fish culture potential for integrating food and health.     

Potential of Amaranthus seeds in supplementary feed and its impact on growth in some carps

Amaranthus seeds were used at three different levels (20%, 35%, 50%) in fish diets under a semi-intensive fish culture system and their impact on the growth of common carp, Cyprinus carpio, and rohu, Labeo rohita, was studied. Growth in terms of body weight gain was maximum in fish fed on diets containing 20% Amaranthus seeds, that replaced rice bran and groundnut oil cake in the feed. Overall, the fish fed on diets containing Amaranthus seeds at different levels showed better growth than the control, because of the good-quality proteins available in Amaranthus seeds. In the two species used, L. rohita showed better growth performance than C. carpio.     

Auxin,Cytokinin, and Ethylene Involved in Rice N Availability Improvement Caused by Endophyte <Emphasis Type="Italic">Phomopsis liquidambari</Emphasis>

Nitrogen (N) is one of the most limiting nutrients for rice yield. There is mounting evidence that the endophytic fungus Phomopsis liquidambari B3 can establish a mutualistic symbiotic relationship with rice, enhancing N uptake and metabolism in rice (Oryza sativa L.). To examine the mechanism underlying the effect of B3 on nitrogen accumulation and metabolism in rice plants, a pot experiment was conducted to examine the N and phytohormone levels in response to endophyte infection at four whole growth durations during exposure to different N levels. Our results showed that the contents of auxin, cytokinin, and ethylene in rice were significantly enhanced by B3 under low N levels at different growth durations; B3 symbiosis increased N accumulation and rice yield and induced the expression of some genes related to N uptake and metabolism. To further verify that B3 symbiosis enhances N use in rice by regulating phytohormones, we performed a hydroponic experiment in which exogenous phytohormones and their specific inhibitors were applied. The results showed that the application of exogenous auxin, cytokinin, and ethylene increased the rice content of nitrogen, and their inhibitors decreased the amount of nitrogen absorbed in rice. As expected, B3 infection alleviated the negative effect caused by inhibitors slightly. In summary, we conclude that P. liquidambari symbiosis may regulate the content of auxin, cytokinin, and ethylene to improve N use in rice.     

The symbiotic microflora associated with the tegument of proteocephalidean cestodes and the intestines of their fish hosts

The indigenous symbiotic microflora associated with the tegument of proteocephalidean cestodes and the intestines of their fish hosts has been investigated in morphological and ecological aspects. The indigenous microflora associated with the cestode tegument consists of the nannobacteria population, which was present obligatorily on the surface of tegument, and the "deep microflora". The deep microflora associates with some few species of parasites only. Each individual host-parasite micro-biocenosis includes specific indigenous symbiotic microorganisms, with the differing microfloras of host intestine and parasite. Physiology, biochemistry and/or diet of hosts apparently influence on the symbiotic microflora's structure of parasites. The least bacteria abundance and diversity of their morphotypes were observed in the parasites from baby fishes. The diversity and abundance of bacteria were increased with the fish host ageing and the formation of the definitive structure of its intestine. It is an evidence of the gradual invading of the intestinal parasites (cestodes) tegument by bacterial cells. The invading is realized on the base of the microflora that was present in the food of fish host. The symbiotic microflora has specific morphological features, can regulate the homeostasis of the cestodes and fish hosts and also can maintain equilibrium of alimentary and immune interrelations in the host-parasite system.     

双歧椰汁米酒实验室生产工艺的研究

目的 以优质糯米和椰汁为原料,通过双歧杆菌和酿酒酵母共生发酵研制出一种功能性的米酒.方法 采用正交试验设计的方法得到了双歧杆菌和酿酒酵母最佳的共生发酵条件.结果 最佳的共生发酵条件是:发酵温度35℃、双歧杆菌接种量3％、酿酒酵母接种量2％、发酵时间16 h,再通过添加30％酿酒酵母单独发酵产物之后,研制出双歧椰汁米酒.结论 采用此工艺生产的功能性米酒既有椰汁的果香味又有米酒的醇香味,口感柔和,易于接受.