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Response of Over-summer Hydroponic Lettuce to Nutrient Solution Temperature Control 被引量:3
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作者 李锋 陈学东 《Agricultural Science & Technology》 CAS 2017年第6期1072-1075,共4页
Temperature, as an important feature of hydroponic nutrient solution, is closely related to dissolved oxygen content of nutrient solution and growth status of plant roots. How to precisely adjust the temperature of nu... Temperature, as an important feature of hydroponic nutrient solution, is closely related to dissolved oxygen content of nutrient solution and growth status of plant roots. How to precisely adjust the temperature of nutrient solution is the key to obtain high quality and high yield of hydroponic vegetables over summer. With Lactuca sativa vat. crispa 'Luosheng No.3' as the test material, the effect of chiller cooling technology on the temperature of nutrient solution, as well as on the yield and quality of Luosheng No.3, in over-summer hydroponic cultivation was studied. The results showed that the chiller cooling technology controlled the nutrient solution temperature in a reasonable range ((20 ± 1)℃) and promoted the growth and dry matter accumulation of Luosheng No.3, instead of affecting the quality. In short, the chiller cooling technology is applicable to the temperature regulation of nutrient solu- tion in hydroponics over summer. 展开更多
关键词 HYDROPONICS nutrient solution temperature control LETTUCE Over sum-mer
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Nutrient patterns and risk of cataract:a case-control study 被引量:1
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作者 Fatemeh Sedaghat Matin Ghanavati +3 位作者 Parisa Nezhad Hajian Sara Hajishirazi Mehdi Ehteshami Bahram Rashidkhani 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第4期586-592,共7页
AIM:To assess the relation between nutrient patterns and cataract risk.METHODS:This is a hospital-based case-control study with 97 cataract patients and 198 matched controls.Dietary consumption was collected through... AIM:To assess the relation between nutrient patterns and cataract risk.METHODS:This is a hospital-based case-control study with 97 cataract patients and 198 matched controls.Dietary consumption was collected through a valid food frequency questionnaire(FFQ).Nutrient patterns were detected by applying factor analysis.Unconditional logistic regression models were used to estimate odds ratio(ORs) and 95%CIs.RESULTS:We extracted 5 main nutrient patterns.Factor 1 included niacin,thiamin,carbohydrates,protein,zinc,vitamin B6 and sodium(sodium pattern).Factor 2 was characterized by oleic acid,monounsaturated fats,polyunsaturated fats,linoleic acid,trans fatty acid,linolenic acid,vitamin E and saturated fats(fatty acid pattern).The third factor represented high intake of vitamin B12,vitamin D,cholesterol and calcium(mixed pattern).The 4^(th) pattern was high in intake of beta and alpha carotene,vitamin A and vitamin C(antioxidant pattern).Finally,the 5^(th) pattern loaded heavily on docosahexaenoic acid(DHA) and eicosapentaenoic acid(EPA)(omega-3 pattern).In crude and multivariate analysis,the sodium pattern was associated with increased risk of cataract(OR=1.97,95%CI:1.09-3.96).The fatty acid pattern elevated the risk of cataract(OR=1.94,95%CI:1.1-3.86).Antioxidant pattern was associated with a significant 79% reduced risk(2^(nd) category compared with the 1st).Omega-3 pattern was significantly negatively associated with risk of cataract(P=0.04).CONCLUSION:These findings imply that nutrient patterns reflecting a combined consumption of nutrients might be important in the etiology of cataract.Additional studies with more efficient designs are warranted to confirm our findings. 展开更多
关键词 nutrient patterns CATARACT case-control study
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Identification of Quantitative Trait Loci Controlling Seed Physical and Nutrient Traits in Cotton
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作者 SONG Xian-liang,ZHANG Tian-zhen(National Key Laboratory of Crop Genetics & Germplasm Enhancement,Cotton Research Institute,Nanjing Agricultural University,Nanjing 210095,China) 《棉花学报》 CSCD 北大核心 2008年第S1期32-,共1页
Cotton(Gossypium spp.) is the leading fiber crop,and an important source of the important edible oil and protein meals in the world.Complex genetics and strong environmental effects hinder
关键词 QTLs Identification of Quantitative Trait Loci controlling Seed Physical and nutrient Traits in Cotton
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Hydrological Controls on Nutrient Exportation from Old-Growth Evergreen Rainforests and <i>Eucalyptus nitens</i>Plantation in Headwater Catchments at Southern Chile
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作者 Carlos E. Oyarzun Pedro Hervé-Fernández +2 位作者 Dries Huygens Pascal Boeckx Niko E. C. Verhoest 《Open Journal of Modern Hydrology》 2015年第2期19-31,共13页
Soil cover disturbances have a direct effect on biogeochemistry, potentially enhancing nutrient loss, land degradation and associated changes in ecosystem services and livelihood support. The objective of this study w... Soil cover disturbances have a direct effect on biogeochemistry, potentially enhancing nutrient loss, land degradation and associated changes in ecosystem services and livelihood support. The objective of this study was to assess how canopy affected throughfall chemistry and how hydrology affected stream nutrient load responses in two watersheds dominated by native old-growth evergreen rainforest (NF) and exotic plantation of Eucalyptus nitens (EP), located at the Coastal mountain range of southern Chile (40&deg;S). We measured nitrogen (NO3-N, NH4-N, Organic-N, Total-N) and total phosphorus (Total-P) at catchment discharge, and δ18O in throughfall precipitation and stream discharge in both catchments, in order to separate throughfall (or new water) contributions during storm events. It was hypothesized that all nutrients showed an increase in concentration as discharge increased (or enhanced hydrological access), in EP;but not in NF. Our results indicated that Organic-N, Total-N and Total-P concentrations were positively related to discharge. However, NO3<sup style="margin-left:-7px;">--N showed a negative correlation with catchment discharge. Organic-N and Total-P showed a flush during storm events;the opposite was observed for NO3<sup style="margin-left:-7px;">--N. However, this behavior suggested that NO3<sup style="margin-left:-7px;">--N was being retained by charged particles or soil micro biota, whether Organic-N was flushed as it was more concentrated in big pore water that was not tightly attached, compared with NO3<sup style="margin-left:-7px;">--N. 展开更多
关键词 Native RAINFORESTS Exotic Plantations nutrient Fluxes HYDROLOGICAL controlS HEADWATER Catchments
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An Electro-Mechanical Controller for Adjusting Piston Pump Stroke On-the-Go for Site-Specific Application of Crop Nutrients
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作者 Ali Mirzakhani Nafchi Joe Mari Maja +6 位作者 Ahmad Khalilian Young Han Nicholas Rogers Jose O. Payero Michael W. Marshall Phillip B. Williams Jonathan Fox 《Agricultural Sciences》 2017年第9期949-959,共11页
Nutrient application systems are designed to apply a relatively uniform amount of a fertilizer to agricultural fields. However, considerable variation in soil texture and other characteristics often occurs within and ... Nutrient application systems are designed to apply a relatively uniform amount of a fertilizer to agricultural fields. However, considerable variation in soil texture and other characteristics often occurs within and across production fields, which could have a major impact on fertilizer management strategies. Therefore, uniform application of a fertilizer over the entire field can be both costly and environmentally unsound. Due to their rugged and fool-proof design, crankshaft type piston pumps are widely used in agriculture. The on-the-go outlet flow of these pumps can only be varied by changing the drive shaft speed for each pump stroke setting. But only a limited range of flow rates can be achieved by changing the drive shaft speed. There is a need for an electronic controller, which can adjust the pump stroke on-the-go, for real-time, variable-rate application of crop nutrients. The Clemson “Electro-me-chanical controller for adjusting pump stroke on-the-go” was designed to replace the current manual stroke adjustment system on positive displacement piston pumps. This affordable system can be retrofitted on most John Blue - piston pumps for real-time adjustment of the pump stroke and can be controlled using pre-described position sequences (map-based) or real-time sensor commands (such as optical, pressure, and flow sensors) combined with fertilizer calculation algorithms. In addition, it can adjust pump stroke manually, using an eclectic dial from the tractor’s cab. 展开更多
关键词 Electro-Mechanical controlLER METERING PISTON Pumps nutrient Management Precision Agriculture Pump STROKE
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Can short-term and small-scale experiments reflect nutrient limitation on phytoplankton in natural lakes? 被引量:1
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作者 王海军 李艳 +6 位作者 冯伟松 于清 肖绪诚 梁小民 邵建春 马硕楠 王洪铸 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第3期546-556,共11页
Whether it is necessary to reduce nitrogen(N) and/or phosphorus(P) input to mitigate lake eutrophication is controversial. The controversy stems mainly from differences in time and space in previous studies that suppo... Whether it is necessary to reduce nitrogen(N) and/or phosphorus(P) input to mitigate lake eutrophication is controversial. The controversy stems mainly from differences in time and space in previous studies that support the contrasting ideas. To test the response of phytoplankton to various combinations of nutrient control strategies in mesocosms and the possibility of reflecting the conditions in natural ecosystems with short-term experiments, a 9-month experiment was carried out in eight 800-L tanks with four nutrient level combinations(+N+P,-N+P, +N-P, and-N-P), with an 18-month whole-ecosystem experiment in eight ~800-m^2 ponds as the reference. Phytoplankton abundance was determined by P not N, regardless of the initial TN/TP level, which was in contrast to the nutrient limitation predicted by the N/P theory. Net natural N inputs were calculated to be 4.9, 6.8, 1.5, and 3.0 g in treatments +N+P,-N+P, +N-P, and-N-P, respectively, suggesting that N deficiency and P addition may promote natural N inputs to support phytoplankton development. However, the compensation process was slow, as suggested by an observed increase in TN after 3 weeks in-N+P and 2 months in-N-P in the tank experiment, and after 3 months in-N?+P and ~3 months in-N-P in our pond experiment. Obviously, such a slow process cannot be simulated in short-term experiments. The natural N inputs cannot be explained by planktonic N-fixation because N-fixing cyanobacteria were scarce, which was probably because there was a limited pool of species in the tanks. Therefore, based on our results we argue that extrapolating short-term, small-scale experiments to large natural ecosystems does not give reliable, accurate results. 展开更多
关键词 EUTROPHICATION nutrient control EXTRAPOLATION mesocosm experiment
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Benefit Assessment of Forest Function in Reducing Soil Erosion and Nutrient Loss in Anji County of Taihu Lake Basin
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作者 Biao ZHANG Jixi GAO +2 位作者 Gaodi XIE Changxin ZOU Bin WANG 《Asian Agricultural Research》 2013年第4期93-96,100,共5页
The non-point source pollution arising from soil erosion is one of the main reasons for the deterioration of the water quality of the Taihu Lake Basin. Forest plays an important role in controlling soil erosion and re... The non-point source pollution arising from soil erosion is one of the main reasons for the deterioration of the water quality of the Taihu Lake Basin. Forest plays an important role in controlling soil erosion and reducing nutrient loss. Based on the survey data on forest resources in Anji County, we estimate the amount of soil erosion and nutrient loss of nitrogen and phosphorus reduced by forest, using soil erosion modulus method and soil nutrient content. In accordance with the degradation coefficient of pollutant and regional compensation standards of environmental resources, we assess the ecological benefits of forest function in reducing nutrient loss of nitrogen and phosphorus in Anji County. The results show that the forest in Anji County can reduce the soil erosion amount at 1.51 million t annually on the average, so as to control the nutrient loss of 1 409 t of total nitrogen and 577 t of total phosphorus in soil, equivalent to annually avoiding the flow of 824 t of total nitrogen and 410 t of total phosphorus into river water; this ecological service function can make forests in Anji County get 92.55 million yuan of ecological compensation funds (about 688 yuan/hm2·a), equivalent to 15 times of the current ecological compensation standard (47 yuan/hm2). The study reveals the importance of forest function in controlling soil erosion and nutrient loss in the upper reaches of Taihu Lake Basin to water environment protection in the basin, conducive to carrying out pollution control and protection work of the water environment in the basin. 展开更多
关键词 FOREST Soil erosion. nutrient control BENEFIT asse
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棉隆土壤消毒联合种植密度防除油菜田杂草及对作物产量和田间光照的影响
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作者 朱文达 颜冬冬 +2 位作者 刘晓洪 李林 曹坳程 《植物保护》 CAS CSCD 北大核心 2024年第2期361-365,共5页
在农田杂草的治理中,结合农艺措施来治理草害的发生,可有效减少化学除草剂的使用,实现草害的综合治理。本文采用田间试验研究了棉隆土壤消毒联合油菜不同种植密度对油菜田主要杂草野燕麦Avena fatua、苦苣菜Sonchus oleraceus的防除效果... 在农田杂草的治理中,结合农艺措施来治理草害的发生,可有效减少化学除草剂的使用,实现草害的综合治理。本文采用田间试验研究了棉隆土壤消毒联合油菜不同种植密度对油菜田主要杂草野燕麦Avena fatua、苦苣菜Sonchus oleraceus的防除效果,及杂草对氮、磷、钾及水分消耗的影响。结果表明,土壤消毒联合种植密度对油菜田杂草防除效果显著,对野燕麦、苦苣菜均有良好防效,总鲜重防效达到89.8%~100.0%。采取防除措施后,杂草对田间氮、磷、钾和水分的消耗量减少85%以上,有效改善了田间的水肥和光照条件。土壤消毒联合种植密度不同处理的油菜籽产量达到3155.0~4920.5 kg/hm^(2),增产效果显著,产量较未消毒土壤区增加13.3%~76.8%,增收1857.3~10684.8元/hm^(2)。研究表明采用土壤消毒结合种植密度对油菜田杂草具有很好的控制效果,适度增加油菜种植密度既能保证对杂草防效,同时也能保证产量。 展开更多
关键词 棉隆 种植密度 杂草防效 养分 油菜籽产量
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Removal of Agricultural Non-Point Source Pollutants by Artificial Aquatic Food Web System: A Study Case of the Control of Cynobacterial Bloom in Jiyu River
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作者 Nichun Guo John A. Dowing +3 位作者 Christopher T. Filstrup Deqin Yu Wenhao Ji Youhua Ma 《Open Journal of Ecology》 2016年第12期699-713,共15页
An artificial aquatic food web (AAFW) system was designed to remove the non-point source pollutants in eutrophic Jiyu river. A certain amount of Scenedesmus obliquus and Daphnia pulex was cultured in the system for th... An artificial aquatic food web (AAFW) system was designed to remove the non-point source pollutants in eutrophic Jiyu river. A certain amount of Scenedesmus obliquus and Daphnia pulex was cultured in the system for the control of serious cyanobacterial bloom. The AAFW system was a continuous-flow system including one storage basin of 3 m<sup>3</sup> capacity with polluted river water (the total nitrogen-TN: 4.49 mg&sdot;l<sup>-1</sup><sup></sup>;the total phosphorus-TP: 0.192 mg&sdot;l-1</sup></sup><sup></sup>), one phytoplankton tank of 3 m<sup>3</sup> capacity with an initial concentrations of S. obliquus about 5.8 × 10<sup>3</sup> ind&sdot;l-1</sup><sup></sup>, and one zooplankton growth chamber of 1.5 m<sup>3</sup> capacity with an initial abundance of D. pulex about 22.5 ind&sdot;l-1</sup></sup>. The system was optimized by setting hydraulic retention time of phytoplankton tank as 5 days and the experiments were operated for 45 days. Compared with the polluted river, TN and TP were removed about 28% and 47% by the AAFW system, respectively. The biomass of phytoplankton decrease from 6.33 mg&sdot;l-1<sup></sup> to 1.48 mg&sdot;l-1</sup><sup></sup> and the percentage of cyanobacteria decrease from 43.93% to 2.36%, the biomass of Crustacean zooplankton increase from 0.34 mg&sdot;l-1</sup></sup><sup></sup> to 1.53 mg&sdot;l-1</sup></sup><sup></sup> and the percentage of D. pulex increase from 19.19% to 57.62%. Our results indicated that the AAFW system not only is an efficient, flexible system for reducing nutrient levels in tributary rivers, but also has an ability to control the cyanobacteria bloom and rebuilding the aquatic ecosystem from the polluted river water. 展开更多
关键词 Non-Point Source Pollutants Artificial Aquatic Food Web System Reducing nutrient Levels Cyanobacterial Bloom control
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秸秆还田及不同比例控失尿素对华北平原小麦产量及潮土性质影响 被引量:1
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作者 张水清 涂昊泽 +6 位作者 岳克 黄绍敏 张博 宋晓 郭斗斗 张珂珂 岳艳军 《农业资源与环境学报》 CAS CSCD 北大核心 2024年第1期105-112,共8页
为探讨不同控失尿素比例和秸秆还田对华北平原小麦产量及潮土化学性质的影响,本研究以华北潮土区小麦-玉米轮作体系为研究对象,采用裂区试验设计,以秸秆还田为主区,控失尿素比例为副区。秸秆还田模式设秸秆全量还田(S1)、秸秆不还田(S0)... 为探讨不同控失尿素比例和秸秆还田对华北平原小麦产量及潮土化学性质的影响,本研究以华北潮土区小麦-玉米轮作体系为研究对象,采用裂区试验设计,以秸秆还田为主区,控失尿素比例为副区。秸秆还田模式设秸秆全量还田(S1)、秸秆不还田(S0)2种;控失尿素比例设不施肥(CK)以及控失尿素占总施氮量比例为0、40%、70%和100%(LCU0、LCU40、LCU70、LCU100)5个处理。在作物收割后进行产量测定,并采集0~20 cm耕层土壤进行常规土壤养分含量测定。结果表明:与S0处理相比,S1处理显著提高土壤有机质和速效钾含量。控失尿素显著提高土壤硝态氮含量,其他土壤养分含量无显著变化。秸秆不还田条件下,施用化肥显著降低了土壤pH值。控失尿素比例为70%时土壤养分含量最高。秸秆还田对小麦产量及吸氮量无显著影响,控失尿素对小麦产量及吸氮量增加具有极显著影响。在所有处理中,S1-LCU40处理的籽粒和秸秆产量最高,籽粒产量达7009.26 kg·hm^(-2),秸秆产量达11361.38 kg·hm^(-2)。秸秆还田对土壤氮素依存率具有显著影响,不同比例控失尿素对氮素收获指数具有显著影响,对氮肥表观利用率、土壤氮素依存率具有极显著影响。控失尿素比例为40%或70%时氮素吸收利用指标较优。综上,在华北平原潮土区,秸秆还田与40%控失尿素比例配施可以显著提升土壤供氮能力,提高小麦产量和氮素吸收与利用指标,是较为适宜的管理措施,但其机理及长期效应还需进一步研究。 展开更多
关键词 控失尿素 秸秆还田 土壤养分 硝态氮 籽粒产量 氮肥利用率
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消减大豆连作障碍的养分调控技术研究进展 被引量:1
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作者 孙义卓 蔡姗姗 +3 位作者 王伟 郭伟 孙磊 孙海燕 《大豆科学》 CAS CSCD 北大核心 2024年第2期237-244,共8页
为明确不同养分调控技术对大豆连作障碍消减的作用,本文阐述了大豆连作障碍的发生与危害。从提高肥料养分供应能力、改善土壤理化性状和优化土壤微生物环境3个方面分别综述了针对大豆连作障碍中不同危害的解决方案。通过改变施肥方式、... 为明确不同养分调控技术对大豆连作障碍消减的作用,本文阐述了大豆连作障碍的发生与危害。从提高肥料养分供应能力、改善土壤理化性状和优化土壤微生物环境3个方面分别综述了针对大豆连作障碍中不同危害的解决方案。通过改变施肥方式、时间、数量等方式解决大豆长期连作导致土壤中养分偏耗和影响大豆生长发育的问题;通过使用不同改良剂针对性地解决土壤酸化、板结、保水保肥能力下降的问题;在大豆连作土壤中接入有益微生物,从而降低有害微生物及病原菌的活性,最终达到改善土壤微生物环境的效果。最后总结得出,消减大豆连作障碍过程中尚待解决的问题以及养分调控技术的研究方向,为大豆连作障碍的发生发展机理的研究、养分调控技术的优化改良提出建议和展望。 展开更多
关键词 大豆 连作障碍 土壤质量退化 养分调控技术
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控释尿素与普通尿素配施对橡胶树叶片和胶乳养分及产量的影响
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作者 杨红竹 黄艳艳 +4 位作者 冀春花 刘海林 林清火 茶正早 罗微 《热带作物学报》 CSCD 北大核心 2024年第9期1868-1876,共9页
为了明确控释尿素与普通尿素配施在橡胶树上的应用效果,通过2年田间试验,研究了减氮条件下控释尿素与普通尿素不同比例配施对橡胶树产量、叶片和胶乳矿质养分及土壤氮含量的影响,为橡胶树栽培管理中合理施氮提供技术支撑。结果表明:控... 为了明确控释尿素与普通尿素配施在橡胶树上的应用效果,通过2年田间试验,研究了减氮条件下控释尿素与普通尿素不同比例配施对橡胶树产量、叶片和胶乳矿质养分及土壤氮含量的影响,为橡胶树栽培管理中合理施氮提供技术支撑。结果表明:控释尿素与普通尿素配施可提高橡胶树干胶产量和叶片氮含量,与常规施肥相比,橡胶树干胶产量增幅为16.28%~39.13%(2021年)和7.94%~9.69%(2022年),叶片氮含量增幅为10.54%~19.17%(2021年)和10.24%~21.50%(2022年),控释尿素与普通尿素配施处理叶片氮含量均处于正常值以上。控释尿素与普通尿素配施还能够增加胶园肥穴土壤碱解氮含量,较常规施肥增加了11.27%~80.36%。控释尿素与普通尿素配施比例为50∶50时,橡胶树干胶产量(2022年)、叶片氮含量(2021—2022年)和土壤碱解氮含量(2021—2022年)均显著高于常规施肥。综上所述,在本试验条件下,控释尿素与普通尿素配施比例为50∶50能够获得较高的干胶产量,可改善叶片营养状况,维持土壤氮水平,有利于实现橡胶树施肥管理的绿色协同增效。 展开更多
关键词 橡胶树 控释尿素 普通尿素 产量 叶片养分
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湖泊生态系统修复理论与技术研究进展
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作者 唱彤 郦建强 +4 位作者 陈文学 郭旭宁 刘为锋 李云玲 吴凤燕 《水科学进展》 EI CAS CSCD 北大核心 2024年第6期1005-1020,共16页
全球范围内湖泊富营养化日益严重,影响水资源可持续利用,导致生态系统功能退化,威胁社会经济可持续发展和生态安全。本文系统综述了稳态转换、营养盐控制、生物操纵和环境基准等湖泊系统修复基础理论和最新研究进展;结合国内外湖泊修复... 全球范围内湖泊富营养化日益严重,影响水资源可持续利用,导致生态系统功能退化,威胁社会经济可持续发展和生态安全。本文系统综述了稳态转换、营养盐控制、生物操纵和环境基准等湖泊系统修复基础理论和最新研究进展;结合国内外湖泊修复实践,对内外源污染物削减、生物措施、水利措施等修复技术方法进行概述。湖泊修复是一项长期艰巨的任务,针对目前尚未解决的问题和新的变化环境,提出科学建立修复目标、营养盐阈值确定、水生生物群落定量关系、流域管控体系建立等研究展望,以期为湖泊修复提供科学支撑。 展开更多
关键词 富营养化 稳态转换 营养盐控制 生物操纵 环境基准 湖泊修复
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嘉兴海域主要污染物环境容量及总量控制研究
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作者 刘星璐 郭江泓 +2 位作者 张亚力 罗小峰 路川藤 《水利水运工程学报》 CSCD 北大核心 2024年第4期15-26,共12页
嘉兴海域近年来海洋生态环境质量明显退化,实施污染物总量控制作为保证海域环境质量的根本措施之一,有助于嘉兴海域污染物的减排与治理工作,保障嘉兴海域可持续发展能力。基于嘉兴临近海域水动力-水质模型与现场监测结果,依据浙江省近... 嘉兴海域近年来海洋生态环境质量明显退化,实施污染物总量控制作为保证海域环境质量的根本措施之一,有助于嘉兴海域污染物的减排与治理工作,保障嘉兴海域可持续发展能力。基于嘉兴临近海域水动力-水质模型与现场监测结果,依据浙江省近岸海域环境功能区划的水质要求,采用响应系数法与线性规划方法,计算了该海域重要排放口的化学需氧量COD、无机氮与磷酸盐环境容量,并针对削减扩容影响的总量控制措施进行计算与评估。结果表明,研究海域COD总环境容量为2.97×10^(5)t/a,仍有较大富余,而无机氮与活性磷酸盐含量均超四类海水水质标准,超过海域无机氮与磷酸盐环境容量。对现有规划进行合理的量化数值模拟,削减措施尽管减少了一部分扩容引起的COD、无机氮与磷酸盐含量的增加,使其保持平稳,但仍需继续优化污水处理能力,减少氮磷营养盐的排放。研究结果可为沿海城市陆源污染物总量控制研究提供科学依据。 展开更多
关键词 环境容量 氮磷营养盐 总量控制 CJK3D-WEM 嘉兴海域
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新型控释肥料对安徽沿江流域油菜生长和土壤酶活性的影响
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作者 杨梦杰 王慧 +7 位作者 程文龙 韩上 唐杉 卜容燕 李敏 高原 朱林 武际 《安徽农业大学学报》 CAS CSCD 2024年第5期865-871,共7页
为了改善油菜传统施肥模式,设置了对照(CK)、尿素一次性施肥(N_(180-1))、尿素分3次施肥(N_(180-3))和控释尿素一次性施肥(CRU_(180))4个施肥处理,分析了施用新型控释尿素油菜产量及经济效益、肥料利用率、地上部养分累积量和土壤酶活... 为了改善油菜传统施肥模式,设置了对照(CK)、尿素一次性施肥(N_(180-1))、尿素分3次施肥(N_(180-3))和控释尿素一次性施肥(CRU_(180))4个施肥处理,分析了施用新型控释尿素油菜产量及经济效益、肥料利用率、地上部养分累积量和土壤酶活性的影响。结果表明,CRU_(180)和N_(180-3)处理的产量高于N_(180-1)处理,CRU_(180)的产量比N_(180-3)处理提高了6.77%。CRU_(180)处理的总收入高于N_(180-3)处理1050元·hm^(–2),纯收入比N_(180-3)处理增加了720元·hm^(–2)。与N_(180-1)处理相比,CRU_(180)和N_(180-3)处理的氮肥利用率提高了81.15%%和87.07%,偏生产力分别提高了58.57%和59.43%。CRU_(180)和N_(180-3)处理的薹期养分累积总量分别高于N_(180-1)处理10.85%和46.54%,成熟期养分累积总量分别高于N_(180-1)处理41.67%和40.77%。薹期内CRU_(180)处理的脲酶活性比N_(180-3)、N_(180-1)处理分别提高了42.31%和37.04%,与N_(180-1)处理相比,成熟期内CRU_(180)和N_(180-3)处理的土壤脲酶活性分别提高了22.58%和7.53%,蔗糖酶活性分别提高了12.34%和12.63%,均达到显著性差异。相关性分析表明脲酶、蔗糖酶活性与油菜养分累积量、产量之间呈显著正相关关系。综上结合油菜产量、氮肥利用率、土壤酶活性和经济效益,施用新型控释尿素是一种较好的施肥方式。 展开更多
关键词 油菜 控释尿素 养分累积 土壤酶活性 肥料利用率
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温度敏感型缓/控释肥料的温度响应特征、养分释放性能与温敏机理研究进展
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作者 李娟 杨相东 《植物营养与肥料学报》 CAS CSCD 北大核心 2024年第9期1812-1822,共11页
温度是影响缓/控释肥料养分释放特性的重要因素,开发温度敏感型缓/控释肥料可以使肥料养分释放与作物养分需求更加匹配,从而提高肥料利用效率,促进农业可持续发展。本文综述了聚酰胺类、聚醚类、聚酯类、多糖类以及温敏聚氨酯等常见的... 温度是影响缓/控释肥料养分释放特性的重要因素,开发温度敏感型缓/控释肥料可以使肥料养分释放与作物养分需求更加匹配,从而提高肥料利用效率,促进农业可持续发展。本文综述了聚酰胺类、聚醚类、聚酯类、多糖类以及温敏聚氨酯等常见的温敏聚合物材料的来源、类型和机理,详细阐述了聚N-异丙基丙烯酰胺(PNIPAM)、聚N-乙烯基己内酰胺(PNVCL)、环氧乙烷/环氧丙烷嵌段共聚物(EO/PO)、甲基纤维素和温敏聚氨酯等常见温敏聚合物材料用作温敏缓/控释肥料包膜材料的国内外研究进展,并评估了其在温敏缓/控释肥料中应用的可行性与优缺点。根据温敏特性,将温敏缓/控释肥料分为低临界溶解温度(LCST)响应型和结晶转变温度(Tm)/玻璃化转变温度(Tg)响应型两大类,并详细总结了这两种类型的制备方法、特征、养分释放性能以及分子作用机制。最后,指出温敏型缓/控释肥料的研发尚处于初级阶段,未来应深入开展天然高分子温敏材料的基础研究和创新,筛选绿色可生物降解温敏聚氨酯材料,研发作物和区域专用型温敏缓/控释肥料。 展开更多
关键词 温敏聚氨酯 缓/控释肥料 温度敏感型肥料 温度响应特征 养分释放机理
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控释肥联合养分增效剂显著提高番茄产量与品质
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作者 孙明 解环环 +5 位作者 刘德锐 吕臣浩 赵竹青 刘瑶 陈娥 陈永波 《湖北农业科学》 2024年第2期84-87,93,共5页
采用田间试验,以番茄(Lycopersicon esculentum Mill.)品种瑞菲为试验材料,通过控释肥联合养分增效剂探究其对番茄生长、产量与品质的影响。结果表明,控释肥联合养分增效剂能显著增加植株茎粗(P<0.05);与常规施肥相比,控释肥和控释... 采用田间试验,以番茄(Lycopersicon esculentum Mill.)品种瑞菲为试验材料,通过控释肥联合养分增效剂探究其对番茄生长、产量与品质的影响。结果表明,控释肥联合养分增效剂能显著增加植株茎粗(P<0.05);与常规施肥相比,控释肥和控释肥联合养分增效剂可显著改善番茄品质,番茄果实可溶性固形物含量有增加的趋势,可溶性糖含量、维生素C含量显著提高(P<0.05),番茄果实色泽度和硬度均有所改善;与常规施肥相比,控释肥和控释肥联合养分增效剂能有效提高番茄产量与经济效益,产量分别增加12.7%和29.2%,净利润分别增加3.65万元/hm^(2)和7.72万元/hm^(2)。综上,控释肥联合养分增效剂可实现番茄增产增效,在实现轻简化生产中具有重要的实践价值。 展开更多
关键词 控释肥 养分增效剂 番茄(Lycopersicon esculentum Mill.) 产量 品质
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不同营养元素对秋月梨木栓病的影响
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作者 李浩洁 熊国宇 +3 位作者 曹丽 曾昊 衡伟 叶振风 《现代农业科技》 2024年第23期84-88,94,共6页
秋月梨是一种于2002年引自日本的中晚熟砂梨品种,因其品质优良而深受消费者和果农喜爱。然而,秋月梨果实木栓病严重影响其品质,给市场销售带来不利影响,成为制约该品种发展的关键因素。为了明确秋月梨果实木栓病发生的原因,并探索相应... 秋月梨是一种于2002年引自日本的中晚熟砂梨品种,因其品质优良而深受消费者和果农喜爱。然而,秋月梨果实木栓病严重影响其品质,给市场销售带来不利影响,成为制约该品种发展的关键因素。为了明确秋月梨果实木栓病发生的原因,并探索相应的防治技术,以秋月梨为试材,喷施不同浓度的钙、硼、硅、氨基酸复配剂,然后调查果实发病率,并进行生理生化分析试验研究。结果表明,无水氯化钙0.2%、硼酸0.02%、有机硅0.025%和氨基酸0.07%复配组合对秋月梨木栓病的综合防治效果最佳。 展开更多
关键词 秋月梨 营养元素 木栓病 防治措施
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控释尿素配比对华南双季稻产量、氮素吸收累积及氮肥利用率的影响
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作者 易琼 吴腾飞 +5 位作者 曾招兵 唐拴虎 付弘婷 李苹 戴文举 张木 《南方农业学报》 CAS CSCD 北大核心 2024年第5期1307-1316,共10页
【目的】探讨2种不同释放期控释尿素不同配施模式对水稻产量、氮素吸收累积及氮肥利用率的影响,以期为我国华南双季稻区优化施氮提供科学依据。【方法】采用田间试验,设6个处理:T1,不施氮处理;T2,速效氮肥单施处理;T3,60 d控释尿素单施... 【目的】探讨2种不同释放期控释尿素不同配施模式对水稻产量、氮素吸收累积及氮肥利用率的影响,以期为我国华南双季稻区优化施氮提供科学依据。【方法】采用田间试验,设6个处理:T1,不施氮处理;T2,速效氮肥单施处理;T3,60 d控释尿素单施处理;T4,90 d控释尿素单施处理;T5,60 d控释尿素配施处理(30%60 d控释尿素+70%速效氮肥);T6,90 d控释尿素配施处理(30%90 d控释尿素+70%速效氮肥)。动态分析不同处理的水稻叶片SPAD值,灌浆后地上部、剑叶、穗部氮含量及干物重;收获期测定水稻产量及产量构成因素;计算不同施肥处理的氮肥利用效率。【结果】由早、晚稻年平均产量可知,施用控释尿素的T3~T6处理较速效氮肥单施的T2处理产量显著增加(P<0.05,下同),增幅为4.7%~8.5%。其中,T5处理产量(5.8 t/ha)最高,显著高于T3和T4处理,但与T6处理差异不显著(P>0.05)。与T1处理相比,施用氮肥提高了早稻剑叶SPAD值,T6处理的剑叶SPAD值一直处于较高水平,且始终高于T5处理,T3处理的剑叶SPAD值总体高于T4处理。T5处理产量较高归因于其有效穗数和穗粒数同时保持较高水平。随着时间的推移,水稻植株地上部氮含量逐渐下降,而干物重逐渐增加,且各处理不同部位干物重存在明显差异,至收获期,T5和T6处理穗干物重均显著高于T2处理,但T5处理地上部氮素累积量相对低于其他施氮处理。各控释尿素处理的氮素表观回收率和氮肥农学效率均显著高于T2处理,其中氮素表观回收率以T3处理最高(35.7%),氮肥农学利用率以T5处理最高(7.3%)。【结论】等氮肥用量下,30%60 d控释尿素配施70%速效氮肥处理在提高籽粒产量和养分利用效率方面具有优势,可作为华南双季稻区的推荐施肥模式。 展开更多
关键词 控释尿素 养分配施 氮素吸收积累 氮肥利用率 产量
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增施菌剂对玉米产量、土壤养分、光合特性及病虫害的影响
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作者 汤培升 《江西农业学报》 CAS 2024年第4期72-76,99,共6页
选取4块玉米标准样地,设置了不施肥(CK)、常规施肥(Z_(1))、化肥+西多里微生物菌剂(Z_(2))、化肥+聚谷氨酸复合微生物菌剂(Z_(3))等4个处理,分析了不同菌剂对玉米产量、土壤养分、光合特性及病虫害防治的影响。结果表明:在玉米产量方面... 选取4块玉米标准样地,设置了不施肥(CK)、常规施肥(Z_(1))、化肥+西多里微生物菌剂(Z_(2))、化肥+聚谷氨酸复合微生物菌剂(Z_(3))等4个处理,分析了不同菌剂对玉米产量、土壤养分、光合特性及病虫害防治的影响。结果表明:在玉米产量方面,增施菌剂处理后的行粒数、千粒重和产量均高于CK,其中以Z_(3)处理最佳;在土壤养分方面,Z_(1)~Z_(3)处理在拔节期、乳熟期、成熟期的有机质含量均高于CK,以Z_(3)处理为最高;增施菌剂处理后的土壤碱解氮含量均显著高于CK,具体表现为Z_(3)>Z_(2)>Z_(1)>CK;Z_(3)、Z_(2)、Z_(1)处理的土壤速效磷含量在拔节期、乳熟期和成熟期分别是CK的1.78、1.42、1.15倍,1.76、1.48、1.19倍和2.46、1.95、1.47倍;Z_(3)处理的土壤速效钾含量在拔节期、乳熟期和成熟期分别是Z_(2)、Z_(1)处理及CK的1.30、1.17、1.07,1.28、1.19、1.07倍和1.39、1.19、1.09倍;净光合速率和蒸腾速率在乳熟期达到峰值,其中Z_(3)处理的净化光合速率显著高于其他处理,其蒸腾速率分别是Z_(2)、Z_(1)处理及CK的1.51、1.34、1.24倍;在病虫害防治方面,Z_(1)~Z_(3)处理的病株率显著低于CK。综上,增施菌剂可提高玉米产量,改善土壤养分,增强光合特性,减少病虫害,其中化肥+聚谷氨酸复合微生物菌剂的优势最为明显,可在玉米种植中推广应用。 展开更多
关键词 菌剂 玉米产量 土壤养分 光合特性 病虫害防治
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