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Effects of Rice-duck Mutualism on Diseases Insect Pests and Weeds and Economic Benefits 被引量:1
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作者 邓强辉 潘晓华 《Agricultural Science & Technology》 CAS 2008年第1期128-133,138,共7页
[Objective] Study on the effects of rice-duck mutualism on weeds and insects pests and economic benefits of paddy field. [Method] Comparison of the incidence of weeds, sheath blight and insects pest under rice-duck mu... [Objective] Study on the effects of rice-duck mutualism on weeds and insects pests and economic benefits of paddy field. [Method] Comparison of the incidence of weeds, sheath blight and insects pest under rice-duck mutualism, conventional cultivation and control treatment, the yield and economic benefits were analyzed under the 3 treatments. [Result] Average occurrence of weeds in rice-duck mutualism group decreased by 2.33 and 52.0g ind/m^2 compared with that in conventional cultivation and control treatment ; the control rate of mutualism was up to 75% against rice hopper, but just between 25% -60% against rice leaf roller and Chilo suppressalis. The rates of diseased plant and diseased bell against rice sheath blight were higher and disease indices were lower compared with control group. The yield of mutualism group was identical with conventional cultivation, Which was greatly higher than that of control group. The results suggested an higher economic benefits and lower cost benefit ratio for rice-duck mutualism treatment. [Conclusion] Rice-duck mutualism gives birth to a positive effect to control the diseases, insect pests and weeds, as well as to economic benefits, providing basis on extension of rice-duck mutualism system. 展开更多
关键词 Rice-duck mutualism Disease insect pest and weeds Economic benefits
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Responses of Seed Yield and Economic Benefit of Winter Oilseed Rape(Brassica napus L.) to Different NPK Ratio and Dose 被引量:2
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作者 Yingzi WANG Chang TIAN +5 位作者 Xuan ZHOU Wenming WANG Jianwei PENG Zhenhua ZHANG Haixing SONG Chunyun GUAN 《Agricultural Science & Technology》 CAS 2015年第11期2361-2366,共6页
Field experiments were conducted during 2008-2010 to investigate the ef- fects of NPK fertilization on seed yield and economic benefit of a new hybrid cultivar of winter oilseed rape (Brassica napus L.) - Xiangzayou... Field experiments were conducted during 2008-2010 to investigate the ef- fects of NPK fertilization on seed yield and economic benefit of a new hybrid cultivar of winter oilseed rape (Brassica napus L.) - Xiangzayou763, and to determine the optimum NPK ratio and dose in Hunan, China. The results showed that NPK ratio (1:0.50:0.50) with 180 kg/hm2 N, 90 kg/hm2 P2O5 and 90 kg/hm2 K20 was the optimum combination for the highest seed yield (2 231.13 kg/hm2) and economic benefit (9 816.97 Yuan/hm2), of which 1 641.23 Yuan/hm2 being set for fertilizer in- vestment (VCR=4.11). Besides, the effects of N, P and K fertilizers on seed yield and oil production of winter oilseed rape were not identical. N had the greatest ef- fect on plant growth of winter oilseed rape, followed by P and K. Total leaf number, green leaf number, leaf length and width, rhizome diameter, branch number, dry weight per plant and other agronomic characters in high N treatments were higher than those in low N treatments. By correlation and path analysis of yield components, the contribution rate to seed yield was found: effective silique number per plant〉seed number per silique〉l 000-seed weight. 展开更多
关键词 NPK ratio anddose Seed yield Economic benefit Winter oilseed rape
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Operation Benefit of Fruit Dealers in Shizishan Street Farm market
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作者 Wei SHI 《Asian Agricultural Research》 2017年第4期29-33,36,共6页
This paper mainly discussed the operation benefits of fruit dealers in farm market. Taking fruit dealers in Shizishan Street Farm market in Wuhan City as the research object,this paper introduced current operation sit... This paper mainly discussed the operation benefits of fruit dealers in farm market. Taking fruit dealers in Shizishan Street Farm market in Wuhan City as the research object,this paper introduced current operation situation of fruit dealers and made a descriptive statistical analysis on characteristics of operators,operation situation,and cognitive status. Besides,it introduced the concept of net cost-benefit ratio to reflect the operation benefits. From further analysis on the operation benefits of fruit dealers,it found that there is little difference in the costbenefit ratio between dealers in the farm market. The average net cost-benefit ratio was 11. 94%. Specifically,if the total cost is 100 yuan,the dealer can obtain 12 yuan net profit. In order to find out how cost factors affect the operation benefits,it established a regression model for cost factors and net cost-benefit ratio. According to the survey results,when the wholesale cost increases 10000 yuan,the cost-benefit ratio will increase by 1. 454 percentage points,thus increasing the wholesale investment is helpful for increasing the net cost-benefit ratio; when the loss cost increases 10000 yuan,the cost-benefit ratio will increase by 7. 501 percentage points,thus the dealers can increase the operation benefits through controlling the loss cost and reducing the operation cost. Finally,it came up policy recommendations from the perspective of government and operators. 展开更多
关键词 Farm market Fruit dealers Operation benefits Net cost-benefit ratio
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Analysis on Waxy Corn/Soybean Intercropping Pattern and Economic Benefit 被引量:1
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作者 秦燕 郭泓鋆 +4 位作者 杨进 赵永康 杨洪 韩庆新 李兰 《Agricultural Science & Technology》 CAS 2016年第1期48-50,共3页
The research mainly analyzed effects of waxy corn/soybean intercropping on yields of the two crops, as well as agronomic characters, and the economic benefits of the mode. The results showed that although yields of wa... The research mainly analyzed effects of waxy corn/soybean intercropping on yields of the two crops, as well as agronomic characters, and the economic benefits of the mode. The results showed that although yields of waxy corn and soybean went down by 21.19% and 31.04% per unit area, land equivalent ratio(1.48) kept higher than 1, suggesting the intercropping improves land use rate. Besides, due to the practice of intercropping, many characters of waxy corn grew, but of soybean declined. The economic benefits from high to low were waxy corn/soybean intercropping, monoculture of waxy corn, and monoculture of soybean. 展开更多
关键词 Waxy corn/soybean intercropping Land equivalent ratio Economic benefit
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Effects of Dietary Concentrate to Forage Ratios on Production Performance and Serum Biochemical Indicators in Post-fattening Hainan Yellow Cattle 被引量:4
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作者 Wang Feng Wei Limin +6 位作者 Zheng Xinli Liu Hailong Sun Ruiping Chao Zhe Huang Lili Fu Liang Liu Quanwei 《Animal Husbandry and Feed Science》 CAS 2020年第1期17-20,35,共5页
[Objective]The paper was to investigate the effects of dietary concentrate to forage ratios on production performance and serum bio-chemical indicators of post-fattening Hainan Yellow Cattle.[Method]Sixteen Hainan Yel... [Objective]The paper was to investigate the effects of dietary concentrate to forage ratios on production performance and serum bio-chemical indicators of post-fattening Hainan Yellow Cattle.[Method]Sixteen Hainan Yellow Cattles with the same genetic backgrounds and similar initial weight of(242.22 ±0.71 kg) were randomly divided into four treatments.Cattles were fed with diets of different concentrate to forage ratios(20:80, group Ⅰ;30:70, Group Ⅱ;40:60, group Ⅲ;50:50, group Ⅳ).The trial lasted 62 d.[Result]The daily gain in experimental group Ⅳ was significantly higher than that in experimental group Ⅱ(P<0.05), but the feed gain ratio in experimental group Ⅳ was lower than those in other ex-perimental groups(P>0.05).The feed intake in experimental group Ⅳ was also markedly higher than those in experimental groups Ⅰ and Ⅱ(P<0.05).Compared with the experimental group Ⅱ, the gross profit of experimental group Ⅳ was significantly promoted(P<0.05).The alanine aminotransferase and aspartate aminotransferase activities in experimental group Ⅱ were markedly higher than those in experimental groups Ⅰ, Ⅲ and Ⅳ.[Conclusion]When the dietary concentrate to forage ratios was 50∶50, the production performance of post-fattening Hainan Yellow Cattle was better. 展开更多
关键词 Concentrate to FORAGE ratios HAINAN YELLOW CATTLE Growth performance Economic benefits SERUM biochemical indicator
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Economic Viability of Smallholder Agroforestry and Beekeeping Projects in Uluguru Mountains, Tanzania: A Cost Benefit Analysis 被引量:2
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作者 Willickister R. Kadigi Yonika M. Ngaga Reuben M. J. Kadigi 《Open Journal of Forestry》 2021年第2期83-107,共25页
Agroforestry and beekeeping are widely promoted as prospective Nature-</span></span><span><span><span style="font-family:""> </span></span></span><span... Agroforestry and beekeeping are widely promoted as prospective Nature-</span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">Based Income Generating Activities (NIGAs) to improve livelihoods while at </span><span style="font-family:Verdana;">the same time enhancing biodiversity conservation in degrading</span><span style="font-family:Verdana;"> agro-ecologies. These activities can diversify and increase famers’ incomes and support in</span><span style="font-family:Verdana;">stinctive biota and fauna resilience. However, evidence to showcase and compare their long-term benefits is scant. We use the case of Uluguru</span><span style="font-family:Verdana;"> Mountains in Tanzania to evaluate and compare viability of agroforestry and beekeeping projects using the Cost</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Benefit Analysis (CBA) approach. The results of analysis yielded positive NPVs for both agroforestry and beekeeping projects at discount rates not higher than 8.2% and 8.5% respectively. Overall, the comparison of economic viability between agroforestry and beekeeping projects revealed that the former was relatively more profitable than the later in terms of both the NPV and Benefit</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Cost Ratio (BCR) criteria. However, the Internal Rate of Return (IRR) for beekeeping was slightly higher than that of agroforestry. Yet, we underscore the fact that these two projects can jointly be implemented to enhance livelihoods of farmers and support biodiversity conservation in the study </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">area </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">and other parts with similar agro-ecologies in developing countries. However, farmers in these agro-ecologies need to be supported by governments and non-government development partners in terms of training and inspiration to shift from orthodox farming to sustainable NIGAs. 展开更多
关键词 Uluguru Mountains Uluguru Forestry Reserve Cost benefit Analysis Net Present Values benefit Cost ratios Nature-Based Income Generating Activities
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Economic profitability of cane based furniture enterprises of Chittagong City Corporation Area, Bangladesh
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作者 M.Alamgir M.A.R.Bhuiyan +1 位作者 M.Jashimuddin M.S.Alam 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第2期153-156,共4页
An exploratory survey was conducted to assess economic profitability of cane based furniture enterprises in Chittagong City Corporation area of Bangladesh. A multistage random sampling was adopted to carry out the stu... An exploratory survey was conducted to assess economic profitability of cane based furniture enterprises in Chittagong City Corporation area of Bangladesh. A multistage random sampling was adopted to carry out the study. Based on the total investment the enterprises were divided into large, medium and small.. Most of the entrepreneurs (55%) are in the age class 40-50 years and only (18.33%)are >50 years. In small and medium category lowest entrepreneurs (8.33% each) are found graduate and 18.33% in large farm. Most of the enterprises are in the small category (45%) and 66.67% labors are skilled whereas only 33.33% are unskilled. Seven articles of sixteen different sizes were identified made from cane, which are Sofa (45 cm × 45 cm, 50 cm × 50 cm and 55 cm × 55 cm), Dinning (4ch. 1tab,and 6ch. 1tab.), Bed (1 m × 2m, 1.3 m × 2.3 m and 1.5 m × 2.3 m), Chair (45 cm × 45 cm and 50 cm ×50 cm), Rocking chair (large size,medium and small size), Dolna (Hanging and Running) and Partition. In all the three category enterprises chair (45 cm × 45 cm) was produced in highest number and the lowest production was Bed (1.5 m × 2.3 m). The total net benefit (2089 US$) and benefit cost ratio (1:16)was the highest for large cane enterprises. So among three categories of the cane enterprises the large enterprises are more profitable than others. 展开更多
关键词 BANGLADESH Cane enterprises Net benefit benefit-cost ratio
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Benefit-cost analysis of raising Pinus wallichiana seedlings in different capacities/sizes of root trainers in the nursery
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作者 Altamash BASHIR K. N. QAISAR +1 位作者 M. A. KHAN Mumtaz MAJEED 《Forestry Studies in China》 CAS 2009年第2期118-121,共4页
Modern nursery methods of seedling production in different sized root trainers, were compared by raising seedlings of Pinus wallichiana involving costs incurred and benefits received. In order to provide a common basi... Modern nursery methods of seedling production in different sized root trainers, were compared by raising seedlings of Pinus wallichiana involving costs incurred and benefits received. In order to provide a common basis for the comparisons, the study involved the raising of 1000 seedlings annually on a continuous basis for seven years. A relative economic analysis of raising P. wallichiana seedlings in 300, 150 and 100 cm^3 root trainers was carried out and we estimated that the root trainers of 300 cm^3 capacity recorded the highest total input cost of Rs. 35571 and Rs. 40018 for 1000 seedlings produced annually at discount rates of 12% and 6%. Seedlings raised in 100 cm^3 root trainers recorded the lowest total input cost of Rs. 23390 and Rs. 27737 per 1000 seedlings annually at discount rates of 12% and 6%. Hence, returns per rupee invested in raising seedlings in the 100 cm^3 root trainers accounted for the maximum benefit-cost ratio (i.e., 1.56 and 1.61) at discount rates of 12% and 6%. Thus seedlings raised in 100 cm^3 and 150 cm^3 root trainers were found to be most cost effective when compared with seedlings grown in 300 cm^3 root trainers. The results can be attributed to the larger number of cells per tray (higher growth density) in the 100 and 150 cm^3 root trainers, compared to the number of seedlings in the 300 cm^3 root trainers. 展开更多
关键词 economics Pinus wallichiana root trainer benefit-cost ratio NURSERY
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Dry Season Feeding Technologies: Assessing the Nutritional and Economic Benefits of Feeding Hay and Silage to Dairy Cattle in South-Western Uganda
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作者 Proscovia Renzaho Ntakyo Halid Kirunda +1 位作者 Gershom Tugume Stephen Natuha 《Open Journal of Animal Sciences》 2020年第3期627-648,共22页
South-western Uganda annually experiences prolonged drought that results in dramatic drop in milk production of dairy cattle. This study was conducted to assess the nutritional value and economic benefits of feeding s... South-western Uganda annually experiences prolonged drought that results in dramatic drop in milk production of dairy cattle. This study was conducted to assess the nutritional value and economic benefits of feeding silage and hay to dairy cattle in the sub-region. The cross-sectional study covered seven districts with 105 farmers interviewed during the wet and 45 others in the dry season. Up to 88 soil samples were collected and analyzed for soil texture, soil pH, organic matter and total Nitrogen, Phosphorus, Potassium, Calcium, Sodium and Magnesium. Likewise, 148 forage (105 fresh, 25 silage and 18 hay) tissues from 21 pasture species were collected and analyzed for nutritional values. Using a questionnaire, data on production costs and milk revenues were collected for cost-benefit analysis. Results showed that silage of Napier grass treated with molasses (10.2 MJ/kg) and hay of naturally established pastures (10.6 MJ/kg) had the highest metabolisable energy (ME) values, while the lowest (8.30 MJ/kg) was for star grass. Hay of star grass presented the highest level of crude protein (21.4%) with maize (corn) showing the lowest (9.38%). Digestibility of hay of naturally established mixed pastures was the highest (64.4%), followed by that of silage of Napier grass treated with molasses (62.0%), while star grass hay had the lowest (52.6%). With exception of silage made from maize, all the other six forms of silage had a good crude protein (CP) content. Regardless of the good CP content (≥9.9%), all silage untreated with additives was poor in quality since its ME was less than 9.9 MJ ME/kg and ration digestibility less than 67%. Nonetheless, feeding of silage and hay increased milk yield and farm productivity with a benefit-cost ratio of 5.5 and 2.7 for silage and hay respectively. 展开更多
关键词 benefit-Cost ratio Hay and Silage Nutritive Values Milk Production
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新业态从业人员参加养老保险的成本收益与收入再分配效应——基于共同富裕视角 被引量:2
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作者 曾益 陆颖 +1 位作者 李殊琦 吴万宗 《财贸研究》 CSSCI 北大核心 2024年第2期1-14,共14页
基于个人和社会角度,意在探讨哪种参保选择能同时满足个人的“成本收益”效应最大化和社会的“收入再分配”效应最大化,以达到推进共同富裕的效果。采用2018年中国劳动力动态调查微观数据(CLDS),构建精算模型研究发现:新业态从业人员基... 基于个人和社会角度,意在探讨哪种参保选择能同时满足个人的“成本收益”效应最大化和社会的“收入再分配”效应最大化,以达到推进共同富裕的效果。采用2018年中国劳动力动态调查微观数据(CLDS),构建精算模型研究发现:新业态从业人员基本养老保险全覆盖可使养老金成本收益比增加,使养老金基尼系数减小;养老金成本收益比随城职保参保率提高而增大,基尼系数随城职保参保率提高而减小;提升城职保参保率与增加缴费指数相结合的政策可以发挥更大的成本收益效应和收入再分配效应。为实现共同富裕的伟大目标,应加快推进新业态从业人员社会保险全覆盖,鼓励新业态从业人员参加城职保。 展开更多
关键词 新业态从业人员 养老保险 成本收益比 收入再分配 共同富裕
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公共健康权益可及性对少数民族流动人口定居意愿的影响 被引量:1
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作者 刘金华 王棫冰 徐典 《西北人口》 CSSCI 北大核心 2024年第1期35-47,共13页
以人口高质量发展支撑中国式现代化,提高人口整体素质是关键。而流动人口公共健康权益的可获得性和可及性程度又是增强流动人口身体素质、定居意愿、城市融入的关键因素。通过分析2018年全国流动人口动态监测数据(China Migrants Dynami... 以人口高质量发展支撑中国式现代化,提高人口整体素质是关键。而流动人口公共健康权益的可获得性和可及性程度又是增强流动人口身体素质、定居意愿、城市融入的关键因素。通过分析2018年全国流动人口动态监测数据(China Migrants Dynamic Survey,简称CMDS),聚焦少数民族流动人口在流入地公共健康权益的现状,进一步使用二分变量对数比回归模型实证分析少数民族流动家庭公共健康权益可及性对定居意愿发生比的影响,关注家庭主要劳动力(个体)和家庭其他成员(幼童、孕产妇)公共健康权益可及性对少数民族流动人口定居意愿的影响,并探讨不同特征的少数民族流动人口健康权益可及性对家庭定居意愿的异质性影响。研究发现:一是公共健康权益可获得性、可及性程度对少数民族流动人口定居意愿存在显著正向影响,且影响效应存在差异。家庭成员公共健康权益的影响效应大于个体影响效应,但孕产妇公共健康权益可获得性与家庭定居意愿没有显著相关关系。二是不同健康权益项目对单个个体健康权益可及性的影响权重不同。健康档案项目对个体公共健康权益的影响效应最大,疫苗接种项目对幼童公共健康权益的影响效应最大,孕产妇四项公共健康权益项目的作用相差不大。三是不同个体获得公共健康权益数量越多,其定居意愿发生比越高,但影响效应不同。公共健康权益可及性程度对于受教育程度低、夫妻两地分居、省内跨市流动的少数民族流动人口定居意愿的影响更大。 展开更多
关键词 公共健康权益可及性 定居意愿 发生比 少数民族流动人口
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果园生草条件下苹果病虫害发生特征
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作者 李晓龙 马军 +9 位作者 褚燕南 岳海英 王芳 岳芬芬 刘婷 李元 王媛 吴昊 贾永华 田建文 《植物保护》 CAS CSCD 北大核心 2024年第6期183-199,共17页
为明确宁夏引黄灌区果园优势功能草种类型并进行获益评价,选用黑麦草Lolium perenne、苜蓿Medicago sativa、高羊茅Festuca arundinacea、长柔毛野豌豆Vicia villosa等4种具备潜在绿肥功能的草种以及自然生草进行果园行间长期生草处理,... 为明确宁夏引黄灌区果园优势功能草种类型并进行获益评价,选用黑麦草Lolium perenne、苜蓿Medicago sativa、高羊茅Festuca arundinacea、长柔毛野豌豆Vicia villosa等4种具备潜在绿肥功能的草种以及自然生草进行果园行间长期生草处理,以清耕模式为对照,对生草试验3年后不同功能草种条件下的果树生长发育及主要病虫害发生状况进行调查,解析不同生草品种条件对果园苹果生长发育、产量品质、病虫害发生情况的综合影响。不同草种生草对苹果生长发育及病虫害的影响不同,即人工播种长柔毛野豌豆、高羊茅、黑麦草及自然生草均可促进果树生育与果实产量品质的提升,减少蚜虫、叶螨发生量,增加瓢虫、草蛉的种群数量。人工播种苜蓿则会显著抑制果树的生育,并使斑点落叶病发生率提高37.62%。果树生长发育与病虫害及天敌发生量的相关性分析表明,果树短枝率与捕食性天敌瓢虫发生量呈显著正相关(R^(2)=0.72),单株产量与捕食性天敌瓢虫(R^(2)=0.64)及草蛉(R^(2)=0.57)发生量呈显著正相关,与叶螨、蚜虫、早期落叶病发生量呈显著负相关(0.462<0.77);此外,捕食性天敌草蛉与瓢虫发生量呈显著正相关,瓢虫与叶螨及蚜虫发生量呈显著负相关(R^(2)>0.62)。综上,果园行间播种长柔毛野豌豆能促进果树生长发育,减少病虫害发生,即果树的获益程度最高,具体表现为(相较于清耕):促进果树生长发育方面,可使短枝率提高15.91%,单果重提高12.62%,可溶性固形物含量提高5.95%,可溶性糖含量提高10.54%,可滴定酸含量降低21.43%,使蚜虫发生量降低36.10%,叶螨发生量降低22.46%,可作为宁夏引黄灌区果园的优势功能草种。 展开更多
关键词 果园生草 苹果 功能草种 生长发育 产量品质 病虫害 获益评价
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控释掺混肥对小麦–玉米轮作体系产量、氮肥利用效率及氨挥发的影响
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作者 曹兵 高玮 +8 位作者 李洪杰 杜梦扬 王学霞 陈延华 倪小会 赵萌 谷佳林 董淑祺 李子双 《植物营养与肥料学报》 CAS CSCD 北大核心 2024年第5期873-885,共13页
【目的】针对华北平原冬小麦-夏玉米轮作体系氮肥施用量大、氮肥利用率低、氮素损失严重等问题,探讨不同配比的控释掺混肥减氮和一次性施肥对周年作物产量、氨挥发损失和施肥经济效益的影响,确立麦玉轮作体系轻简高效和环境友好的施肥... 【目的】针对华北平原冬小麦-夏玉米轮作体系氮肥施用量大、氮肥利用率低、氮素损失严重等问题,探讨不同配比的控释掺混肥减氮和一次性施肥对周年作物产量、氨挥发损失和施肥经济效益的影响,确立麦玉轮作体系轻简高效和环境友好的施肥技术。【方法】于2022—2023年,在山东省德州市现代农业科技园区开展田间试验。冬小麦和夏玉米均设不施氮对照(CK)、农户习惯施氮(FFP)、优化施氮(OPT)、CRBF1(包膜尿素与普通尿素在冬小麦和夏玉米上的掺混比例分别为5∶5和3∶7)和CRBF2(包膜尿素与普通尿素在冬小麦和夏玉米上的掺混比例分别为7∶3和5∶5),共5个处理。基施和追施肥后,监测了氨挥发量、强度和损失率。分析了作物干物质积累和产量、氮素吸收量和氮肥利用效率,并计算了施肥经济效益。【结果】与FFP处理相比,CRBF1和CRBF2处理的夏玉米、冬小麦和周年产量差异不显著;CRBF1和CRBF2处理夏玉米氮肥偏生产力提高了8.87~9.86 kg/kg,CRBF2处理玉米氮肥回收率提高了48.4%(P<0.05);CRBF1和CRBF2处理冬小麦季氮肥回收率、氮肥农学利用率和氮肥偏生产力分别提高了30.3%~37.2%、5.22~5.77 kg/kg和6.52~7.06 kg/kg(P<0.05)。与FFP和OPT处理相比,CRBF1和CRBF2处理的肥料+施肥人工投入减少381~960元/hm^(2),周年净收入增加1208~2654元/hm^(2)。CRBF1和CRBF2处理的周年氨挥发损失量、损失强度和损失率较FFP处理分别降低了69.7%~71.9%、72.0%~74.5%和90.0%~94.1%(P<0.05)。【结论】包膜尿素与普通尿素在冬小麦、夏玉米季按照5∶5、3∶7,或者按照7∶3、5∶5的比例掺混一次性基施,均可在减少氮肥用量和施肥劳力投入的条件下,确保周年作物产量稳定,提高生产效益,并显著降低氨挥发损失,是华北平原冬小麦-夏玉米轮作系统高产高效、轻简施肥的有效氮肥施用技术。 展开更多
关键词 冬小麦-夏玉米轮作 控释掺混肥 一次性基施 氨挥发 产量 氮肥利用效率 经济效益
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非人灵长类动物研究能否得到伦理学辩护?
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作者 邱仁宗 《南京林业大学学报(人文社会科学版)》 2024年第1期11-18,共8页
伦理学研究者的基本工作之一是伦理学辩护。伦理学辩护是通过运用逻辑推理用证据或理由证明已经采取的或建议采取的行动或决策是正确的或合乎伦理的,并可在此基础上,提出政策或法规法律方面的建议。因非人灵长类动物与人类相似,再加上... 伦理学研究者的基本工作之一是伦理学辩护。伦理学辩护是通过运用逻辑推理用证据或理由证明已经采取的或建议采取的行动或决策是正确的或合乎伦理的,并可在此基础上,提出政策或法规法律方面的建议。因非人灵长类动物与人类相似,再加上“高保真”观念的影响,所以估计每年有超过10万的非人灵长类动物被用于生物医学研究。但是,越来越多的人认为这种研究不符合伦理,因为非人灵长类动物跟人一样能够敏感地感受到痛苦,而不能从研究中受益。此外,一些研究表明,人与非人灵长类动物在各种组织和基因类别方面的差异性明显超过相似性,这让一些科学家坚持的“高保真”观念遭到质疑。从伦理学角度,之所以反对非人灵长类动物实验,一是风险-受益比、成本-效益比并不理想,非人灵长类动物受到了非常明显、严重且不可逆的伤害;二是非人灵长类动物的感受能力接近于人,拥有接近于人所具有的完全的道德地位和边缘性人格地位,将其囚禁于实验室,并用于自身不能受益的研究,不符合伦理规范。综合来看,人类应该逐渐用符合伦理、对科学实际有益、更实用、可重复以及风险-受益比和成本-效益比理想的模型取代非人灵长类动物研究。在逐渐取代过程中,若必须使用非人灵长类动物,则需进行伦理审查和风险-受益比的评估,并坚持3R原则。 展开更多
关键词 非人灵长类动物 伦理审查 “高保真”观念 风险-受益比
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不同精粗比饲粮中添加凝结芽孢杆菌对绵羊羔羊生长性能和消化代谢的影响 被引量:4
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作者 王兴岗 张暄梓 +2 位作者 杨代毅 郝小燕 张建新 《动物营养学报》 CAS CSCD 北大核心 2024年第2期1075-1086,共12页
本试验旨在研究不同精粗比条件下饲粮添加凝结芽孢杆菌(BC)对绵羊羔羊生长性能和消化代谢的影响。试验采用2×2因子完全随机设计,2个因素分别为精粗比[40∶60(低精料)、70∶30(高精料)]和BC[不添加和添加1.0×1010CFU/kg BC]。... 本试验旨在研究不同精粗比条件下饲粮添加凝结芽孢杆菌(BC)对绵羊羔羊生长性能和消化代谢的影响。试验采用2×2因子完全随机设计,2个因素分别为精粗比[40∶60(低精料)、70∶30(高精料)]和BC[不添加和添加1.0×1010CFU/kg BC]。选取48只4月龄的杜泊×小尾寒羊F1代公羔,按体重随机分为4个组,分别饲喂低精料饲粮(LD组)、添加BC低精料饲粮(LD+BC组)、高精料饲粮(HD组)、添加BC高精料饲粮(HD+BC组),每组12只。生长性能试验共计70 d,其中预试期10 d,正试期60 d;消化代谢试验共计7 d,其中适应期4 d,取样期3 d。结果显示:1)24只饲喂高精料饲粮羔羊的末重(FBW)和平均日增重(ADG)显著或极显著高于24只饲喂低精料饲粮羔羊(P<0.05或P<0.01),并且料重比(F/G)极显著低于24只饲喂低精料饲粮羔羊(P<0.01);24只饲喂添加BC饲粮羔羊的ADG显著高于24只饲喂不添加BC饲粮羔羊(P<0.05)。2)24只饲喂高精料饲粮羔羊对干物质(DM)、有机物(OM)、中性洗涤纤维(NDF)的表观消化率极显著高于24只饲喂低精料饲粮羔羊(P<0.05),而对酸性洗涤纤维(ADF)的表观消化率则极显著低于24只饲喂低精料饲粮羔羊(P<0.01);24只饲喂添加BC饲粮羔羊对DM、OM、NDF的表观消化率显著高于24只饲喂不添加BC饲粮羔羊(P<0.05)。同时,饲粮精粗比和BC在羔羊对OM和NDF的表观消化率上有显著的交互作用(P<0.05)。HD+BC组的OM和NDF的表观消化率显著高于其他3组(P<0.05)。3)24只饲喂高精料饲粮羔羊的粪能、总能表观消化率、总能代谢率极显著低于24只饲喂低精料饲粮羔羊(P<0.01);24只饲喂添加BC饲粮羔羊的总能表观消化率显著高于24只饲喂不添加BC饲粮羔羊(P<0.05)。饲粮精粗比和BC在粪能和总能表观消化率上有显著的交互作用(P<0.05)。4)24只饲喂高精料饲粮羔羊在氮表观消化率、微生物蛋白(MCP)合成量上显著或极显著高于24只饲喂低精料饲粮羔羊(P<0.05或P<0.01);饲粮精粗比和BC在摄入氮、粪氮、可消化氮、沉积氮、氮沉积率以及血清中尿素氮含量上有显著的交互作用(P<0.05)。综上所述,饲粮中添加BC较不添加BC可提高绵羊羔羊对饲粮中OM、DM、NDF的消化吸收,有效提高总能表观消化率,进而促进羔羊生长。相较饲喂精粗比为60∶40的饲粮,饲喂精粗比为70∶30的饲粮可提高绵羊羔羊对饲粮中OM、DM、NDF的消化吸收,有效提高总能表观消化率、氮表观消化率和MCP合成量,提高羔羊的生长性能。因此,BC可以作为一种新型的益生菌制剂应用于羔羊生产中,且在精粗比为70∶30的高精料饲粮中添加效果更优。 展开更多
关键词 羔羊 精粗比 凝结芽孢杆菌 生长性能 消化代谢 经济效益
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基于客观权重赋权-优劣解距离法的水光互补能源基地补偿效益分摊 被引量:2
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作者 袁文楠 黄显峰 +2 位作者 鲜于虎成 李大成 李旭 《电网技术》 EI CSCD 北大核心 2024年第5期2003-2011,I0058,共10页
针对水光互补系统各电站补偿关系复杂且补偿效益分摊难以量化的问题,提出一种适用于量化水光互补系统效益补偿关系的求解方法,通过对梯级优化调度及水光互补优化调度后发电量的对比,得出水光互补动态过程指标和静态特性指标,建立水光互... 针对水光互补系统各电站补偿关系复杂且补偿效益分摊难以量化的问题,提出一种适用于量化水光互补系统效益补偿关系的求解方法,通过对梯级优化调度及水光互补优化调度后发电量的对比,得出水光互补动态过程指标和静态特性指标,建立水光互补补偿效益分摊模型,并采用改进的客观权重赋权-优劣解距离法(criteria importance through intercriteria correlation-technique for order preference by similarity to an ideal solution,CRITIC-TOPSIS)求解补偿效益分摊比例,明晰各电站之间的损益关系。以澜沧江上游西藏段水光互补清洁能源基地为例进行求解,结果表明该方法考虑梯级水电站与光伏电站间的利益关系,同时兼顾梯级水电站内部的效益得失,分摊结果公平合理,可以平衡各主体之间的利害关系,有利于调动施益主体参与互补运行的积极性,实现清洁能源基地整体效益最大化。 展开更多
关键词 水光互补系统 补偿效益 分摊指标 优化调度 分摊比例
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北方稻渔综合种养新模式效益分析初报
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作者 马亮 李志强 +6 位作者 韩雷 董立强 杨铁鑫 赵旭 吴朝晖 马晓慧 孙富余 《北方水稻》 CAS 2024年第4期26-29,共4页
构建一种北方稻渔综合种养新模式并进行经济效益分析,该模式在稻蟹生态种养的基础上,添加了南美白对虾、中华长臂虾和鲢鳙鱼。结果表明,此模式2022年和2023年水产生物中产值最多是河蟹,达到31212元/hm2和32965元/hm2,产投比最大的为南... 构建一种北方稻渔综合种养新模式并进行经济效益分析,该模式在稻蟹生态种养的基础上,添加了南美白对虾、中华长臂虾和鲢鳙鱼。结果表明,此模式2022年和2023年水产生物中产值最多是河蟹,达到31212元/hm2和32965元/hm2,产投比最大的为南美白对虾,两年分别为17.74和21.32。此模式比水稻单一种植模式增收27809元/hm2和29329元/hm2,对综合效益有正面作用。 展开更多
关键词 稻渔综合种养 产投比 综合效益
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3种瓢虫对西花蓟马和烟粉虱的控制能力研究
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作者 张欢 何恒果 +9 位作者 刘国 余佳敏 刘东阳 邓全 李思翰 张培旭 雍艳萍 伍兴隆 肖科军 蒲德强 《中国农学通报》 2024年第23期143-147,共5页
本研究旨在探讨多异瓢虫、七星瓢虫和十斑大瓢虫这3种天敌昆虫对西花蓟马和烟粉虱的生物防治潜能。在室内条件下,用田间采集的西花蓟马和烟粉虱若虫对3种瓢虫进行不同益害比的饲喂试验,试验过程中记录各处理西花蓟马虫口密度、烟粉虱若... 本研究旨在探讨多异瓢虫、七星瓢虫和十斑大瓢虫这3种天敌昆虫对西花蓟马和烟粉虱的生物防治潜能。在室内条件下,用田间采集的西花蓟马和烟粉虱若虫对3种瓢虫进行不同益害比的饲喂试验,试验过程中记录各处理西花蓟马虫口密度、烟粉虱若虫有咬痕个数及羽化的成虫比例。结果表明,西花蓟马饲喂处理3 d后,3种瓢虫成虫和幼虫对西花蓟马的控制能力由强到弱为:多异瓢虫成虫>七星瓢虫3龄幼虫>七星瓢虫成虫>十斑大瓢虫3龄幼虫>多异瓢虫3龄幼虫>十斑大瓢虫成虫,其中多异瓢虫成虫对西花蓟马的防治效果最高,达到48.35%。烟粉虱若虫饲喂处理3 d后,十斑大瓢虫幼虫处理组中烟粉虱低龄若虫有咬痕的个数占比为2.61%,显著高于对照组,其余处理间没有显著性差异;各处理组烟粉虱成虫羽化率之间没有显著性差异。研究表明,多异瓢虫成虫对西花蓟马的防治效果较高,十斑大瓢虫幼虫对烟粉虱低龄若虫具有一定取食趋性,但3种瓢虫对烟粉虱高龄若虫均没有取食趋性。 展开更多
关键词 西花蓟马 烟粉虱 多异瓢虫 七星瓢虫 十斑大瓢虫 生物防治 益害比 取食趋性
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环境友好型害虫诱捕器对茶园主要刺吸式害虫的诱捕效果
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作者 李隆琦 李远川 +4 位作者 李一璇 刘琦 侯如燕 杨云秋 黄衍章 《湖北农业科学》 2024年第6期81-85,共5页
利用自制环境友好型简易害虫诱捕器,研究不同颜色组合粘虫板对皖南茶园主要刺吸式害虫的诱捕效果及其环境安全性。结果表明,5种颜色组合以金黄-橘红色和金黄-正红色对茶园刺吸式害虫的诱捕效果相对较好,其诱集数量分别为105.6头/盏和10... 利用自制环境友好型简易害虫诱捕器,研究不同颜色组合粘虫板对皖南茶园主要刺吸式害虫的诱捕效果及其环境安全性。结果表明,5种颜色组合以金黄-橘红色和金黄-正红色对茶园刺吸式害虫的诱捕效果相对较好,其诱集数量分别为105.6头/盏和102.4头/盏。以金黄-橘红色、土黄-正红色和橙黄-正红色对益虫的诱集数量较小,分别为16.2、19.4、17.4头/盏,诱集益害比分别为0.15、0.20和0.18,且金黄-橘红色组合粘虫板诱捕的昆虫多样性指数最低(1.767),对茶园生态环境较为友好。利用金黄-橘红色和金黄色粘虫板按495盏/hm~2连续诱捕105 d,对茶园小绿叶蝉的防治效果分别为57.14%和42.86%。 展开更多
关键词 环境友好型害虫诱捕器 茶树 刺吸式害虫 诱捕效果 益害比
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有机肥替代化肥对大棚黄瓜生产的影响 被引量:1
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作者 胡仁健 《安徽农学通报》 2024年第9期28-33,共6页
本研究旨在通过对比分析不同比例有机肥配施对大棚黄瓜生产的影响,筛选出黄瓜种植中有机肥配施最佳比例,为设施黄瓜生产的科学施肥提供参考。本试验在大棚黄瓜上增施有机肥,减施不同数量的化肥,探究其对黄瓜产量、效益和品质的影响。结... 本研究旨在通过对比分析不同比例有机肥配施对大棚黄瓜生产的影响,筛选出黄瓜种植中有机肥配施最佳比例,为设施黄瓜生产的科学施肥提供参考。本试验在大棚黄瓜上增施有机肥,减施不同数量的化肥,探究其对黄瓜产量、效益和品质的影响。结果表明,施用有机肥+减施不同比例的配方肥与习惯施肥比较,均能明显提高黄瓜产量,增产6483.45~11382.60 kg/hm^(2),增幅达10.7%~18.8%,黄瓜种植效益和施肥效应明显增加。生产中增施有机肥同时减施16%化肥,可以达到减少化肥施用量,提高经济效益的效果。此外,施用有机肥能明显降低黄瓜硝酸盐含量,增加其可溶性蛋白含量,降低其有机酸含量,从而改善产品品质。 展开更多
关键词 设施蔬菜 黄瓜 有机肥配比 产量 种植效益 施肥效应 黄瓜品质
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