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1.
青海省是我国乃至亚洲部分其他地区的重要水源地,是我国乃至东半球气候的"启动区"和"调节区",生态地位尤为重要。但是由于地形破碎、土质疏松、植被缺乏、暴雨集中,加之人为扰动剧烈,所以青海省水土流失量大面广。据全国第一次水利普查,全省水土流失面积达到16.87万km2,占土地总面积的24.22%。截至2015年底,青海省共完成水土流失治理面积超过10 557 km2,治理成效显著。搞好水土保持,不仅可以改善青海省的生态系统、维护青海省的生态安全,而且可以改善青海省的农牧业生产条件、推动农牧区发展,保障饮用水源地安全与改善人居环境,推进全省乃至全国的生态文明建设进程。  相似文献   

2.
西藏现代农牧业循环发展模式探讨   总被引:1,自引:0,他引:1  
为充分认识与挖掘农牧业生产发展潜力与有效模式,推进农牧业生产建设与可持续高效发展提供思想借鉴,基于循环经济理论,对西藏不同生态发展区进行实地调查研究,采用具体分析与综合评价结合的方法,对西藏农牧业生产中青稞绿色清洁生产种植,农牧林之间内在与产出有机结合,农业与畜牧业废弃物综合开发利用,草畜与优势资源综合运用以及渔业与植物共存等方面进行了细致的梳理,总结出西藏农牧业循环经济发展模式,即青稞清洁生产型、农牧林种养加结合型、农牧业废弃物综合利用型、高寒草畜暖棚推进型以及鱼菜共养庭院型5种特色发展模式。分别是"减量化、再利用、再循环"的青稞清洁生产体系,以"高效生态养殖、科学种植以及农产品深加工"为一体的农牧林种养加结合体系,"资源优化组合与合理利用"的农牧业废弃物综合利用体系,以"气候特色、草畜平衡与科学养殖"为一体的高寒草畜暖棚体系,"水产养殖与园艺作物共促进"的鱼菜共养庭院体系。上述5种循环模式是西藏不同生态发展区农牧业发展的典型模式,具有各自的发展属性与特色,值得借鉴推广与应用,最后根据分析的结果提出推进西藏农牧业发展循环模式的4项举措与建议。  相似文献   

3.
乐都县位于青海省东部农业区,水、旱、风、雹等自然灾害频繁,农业生产基础薄弱,营造农田防护林对减省自然灾害,促进农牧业发展发挥了重要作用。通过调查研究找出本县农田防护林建设的不足之处,提出了今后发展思路及应采取的措施。  相似文献   

4.
青海省草地资源评价模型   总被引:7,自引:0,他引:7  
利用气象卫生遥感绿度值资料,结合农牧业气象旬报,设计了青海省草地资源评价模型,并对1994年河南县的牧草长势进行了评价分析。  相似文献   

5.
为推广水土保持生态修复,在青海省湟中县大南川流域、上新庄流域开展了黄河上中游水土保持生态修复试点工作。在黄河上中游管理局、青海省水保局等上级部门的大力支持、指导下,湟中县水保部门对生态修复试点工作边实施、边探讨、边总结,以"制定封禁管护制度,加大宣传力度,切实保护植被"为中心,辅以建围栏、设封禁标志牌、补植补种等人工措施,加快植被自我修复;与农、林、牧等部门密切合作,在生态修复试点区配套实施退耕还林(草)、推广太阳灶和沼气池、建设良种奶牛繁育基地等能源、农牧业发展项目,解决了试点区群众取火、养畜、增收等问题。总结了湟中县生态修复试点工作的主要做法和经验。  相似文献   

6.
鄂尔多斯市通过实施禁牧舍饲等水土保持生态修复措施,成功实现了由传统农牧业向现代农牧业的转变。近年来,鄂尔多斯市以农牧业"三区"经济发展规划为指导,统筹城乡发展,实施"收缩转移集中发展"战略,以禁休轮牧及草畜平衡、生态移民、农牧业产业化建设为重要抓手,开创了水土保持生态修复的新局面,为黄河流域加快推行水土保持生态修复提供了典型经验,树立了榜样。建议以国家功能区划总体意见为指导,进一步完善黄河流域水土保持规划,加强流域监督和监测评价,尽快探索和建立水土保持生态补偿机制,以促进流域水土保持生态修复。  相似文献   

7.
当前,内蒙古巴林右旗达林台嘎查农牧区青年人才缺乏的问题,已经严重制约了农牧区的经济社会发展。农牧区大量的劳动力,尤其是有文化层次、受教育程度较高的青年,大量地向城市流动和转移,农牧区几乎成为人才洼地。为了激励青年回流,通过调查分析内蒙古达林台嘎查农牧区本土青年人才回流的情况及不愿回流的原因,提出推动农牧区本土青年人才回流的解决对策。  相似文献   

8.
甘孜州地域辽阔,光热资源丰富,立体气候明显,高原特色农牧业资源得天独厚,是四川生态特色农产品基地的重要组成部分。甘孜州依托丰富的农牧业资源,按照州委州府旅游全域化的战略目标和"一优先、二有序、三加快"的经济发展思路,坚持走"科技、生态、特色、精品、外向"的农牧业发展之路,倾力打造"人无我有、人有我特、人特我精"的特色优势农产品,着力培育"十大产业"。目前,甘孜州面临特色农牧业基础脆弱、产业发展滞后、专业人才匮乏、农民增收难度大等问题,在坚持加快转变农业发展方式、大力发展高原现代特色生态农牧业时,应围绕建基地、扩规模,拓市场、做品牌,建园区、深加工,促改革、给政策等措施,走适度规模化、多样化、特色化之路。  相似文献   

9.
随着社会的发展、经济水平的提高以及科学技术水平的提升,我国的农牧业发展极为快速,先进的科学技术和现代化的农牧生产方法有效提升了农牧业的生产水平和产品质量。气象服务的信息能够有效提升农牧业的生产安全,根据气象服务信息农牧业企业可以做出精准的判断,并通过采取必要的措施减少气象因素对农牧业造成的影响,切实提高农牧业对灾害的防御效果。基于此,对气象为农牧业服务工作中存在的问题进行分析,并提出相应的发展策略。  相似文献   

10.
本文详细剖析了西藏农牧业标准的现状及存在问题,并结合藏区农牧业产业发展迫切需要,提出了西藏农牧业标准发展的对策建议。  相似文献   

11.
Heat and alkali treatments of foods, widely used in food processing, result in the formation of dehydro and cross-linked amino acids such as dehydroalanine, methyldehydroalanine, beta-aminoalanine, lysinoalanine (LAL), ornithinoalanine, histidinoalanine (HAL), phenylethylaminoalanine, lanthionine (LAN), and methyl-lanthionine present in proteins and are frequently accompanied by concurrent racemization of L-amino acid isomers to D-analogues. The mechanism of LAL formation is a two-step process: first, hydroxide ion-catalyzed elimination of H(2)S from cystine and H(2)O, phosphate, and glycosidic moieties from serine residues to yield a dehydroalanine intermediate; second, reaction of the double bond of dehydroalanine with the epsilon-NH(2) group of lysine to form LAL. Analogous elimination-addition reactions are postulated to produce the other unusual amino acids. Processing conditions that favor these transformations include high pH, temperature, and exposure time. Factors that minimize LAL formation include the presence of SH-containing amino acids, sodium sulfite, ammonia, biogenic amines, ascorbic acid, citric acid, malic acid, and glucose; dephosphorylation of O-phosphoryl esters; and acylation of epsilon-NH(2) groups of lysine. The presence of LAL residues along a protein chain decreases digestibility and nutritional quality in rodents and primates but enhances nutritional quality in ruminants. LAL has a strong affinity for copper and other metal ions and is reported to induce enlargement of nuclei of rats and mice but not of primate kidney cells. LAL, LAN, and HAL also occur naturally in certain peptide and protein antibiotics (cinnamycin, duramycin, epidermin, nisin, and subtilin) and in body organs and tissues (aorta, bone, collagen, dentin, and eye cataracts), where their formation may be a function of the aging process. These findings are not only of theoretical interest but also have practical implications for nutrition, food safety, and health. Further research needs are suggested for each of these categories. These overlapping aspects are discussed in terms of general concepts for a better understanding of the impact of LAL and related compounds in the diet. Such an understanding can lead to improvement in food quality and safety, nutrition, microbiology, and human health.  相似文献   

12.
Nitrofurans were broadly used as an extremely effective veterinary antibiotic especially in pig and poultry production farms. Because of fears of the carcinogenic effects on humans, the nitrofurans were banned from use in livestock production in many countries, including the European Union. The present study examines the accumulation, distribution, and depletion of furaltadone and nifursol and of their tissue-bound metabolites [3-amino-5-morpholinomethyl-2-oxazolidinone (AMOZ) and 3,5-dinitro-salicylic acid hydrazine (DNSAH), respectively, in poultry edible tissues (muscle, liver, and gizzards) following administration to chickens of therapeutic and subtherapeutic concentrations of both compounds. Nitrofurans determination was performed by high-performance liquid chromatography-diode array detection and liquid chromatography-tandem mass spectrometry, respectively, for feeds and for poultry tissues. Furaltadone and nifursol, in very low concentrations, were found in samples of muscle, liver, and chicken's gizzard collected from slaughtered animals after 5 weeks of treatment and no withdrawal time period. When a withdrawal time period of 3 weeks was respected, no detectable nitrofuran parent compounds was observed in all of the studied matrices. For AMOZ, concentrations of 270 μg/kg in meat, 80 μg/kg in liver, and 331 μg/kg in gizzard were determined after administration of a medicated feed with furaltadone (132 mg/kg), 3 weeks after withdrawal of treatment. For DNSAH, the concentration values obtained are much lower than those observed for AMOZ. For meat, liver, and gizzard, DNSAH concentrations of 2.5, 6.4, and 10.3 μg/kg, respectively, were determined, after administration of a medicated feed with nifursol (98 mg/kg), 3 weeks after withdrawal of treatment. The gizzard could be considered a selected matrix for nitrofuran residues evaluation in poultry, due to its capacity of retaining either nitrofuran parent compounds or metabolites in higher concentrations, regardless of the administered dose or of the respected withdrawal time period.  相似文献   

13.
Among plant-derived odorants, damascenone is one of the most ubiquitous, sometimes occurring as an apparent natural product but more commonly occurring in processed foodstuffs and beverages. It has been widely reported as a component of alcoholic beverages, particularly of wines made from the grape Vitis vinifera . Although damascenone has one of the lowest ortho- and retronasal detection thresholds of any odorant, its contribution to the sensory properties of most products remains poorly understood. Damascenone can be formed by acid-catalyzed hydrolyses of plant-derived apocarotenoids, in both aglycon and glycoconjugated forms. These reactions can account for the formation of damascenone in some, but not all, products. In wine, damascenone can also be subject to degradation processes, particularly by reaction with sulfur dioxide.  相似文献   

14.
The total phenolics and antioxidant activities of fenugreek, green tea, black tea, grape seed, ginger, rosemary, gotu kola, and ginkgo extracts, vitamin E, and tert-butylhydroquinone, were determined. Grape seed and green tea were analyzed for their phenolic constituents using high-performance liquid chromatography. The total phenolics of the plant extracts, determined by the Folin-Ciocalteu method, ranged from 24.8 to 92.5 mg of chlorogenic acid equivalent/g dry material. The antioxidant activities of methanolic extracts determined by conjugated diene measurement of methyl linoleate were 3.4-86.3%. The antioxidant activity of the extracts using chicken fat by an oxidative stability instrument (4.6-10.2 h of induction time) followed a similar trend in antioxidant activity as determined by the Folin-Ciocalteu method. Seven phenolics in grape seed and green tea extracts were identified that ranged from 15.38 to 1158.49 and 18.3 to 1087.02 mg/100 g of extract, respectively. Plant extracts such as green tea and grape seed extracts can be used to retard lipid oxidation in a variety of food products.  相似文献   

15.
This study was conducted to determine relationships between Al toxicity and mineral uptake of triticale (X Triticosecale, Wittmack), wheat (Triticum aestivum L.), and rye (Secale cereale L.). Two culti‐vars of each species were grown in 1/5‐strength Steinberg solution with 0, 3, 6, or 12 ppm Al added. The solutions were adjusted to pH 4.8 at transplanting and were not adjusted thereafter. The plants were grown in a growth chamber for 19 days before harvesting to determine nutrient solution pH, dry weights, and Al, Ca, Mg, K, and P levels in plants. Increasing Al concentration reduced the final pH of solutions. The addition of 12 ppm Al severely reduced the growth and increased Al concentration of plant tops. The Al levels in roots generally increased with increments of added Al up to 6 ppm. Increasing Al decreased the uptake of Ca, Mg, and P by plant tops more than that of K. Regression analyses indicated that Al toxicity was associated with increasing K/Ca + Mg equivalent ratios and decreasing P concentration in plant tops. Differences between species were: higher Al concentration in rye than wheat with 6 and 12 ppm Al, higher translocation of Ca from roots to tops in wheat than in rye and Mg in triticale and wheat than rye; K/Ca + Mg equivalent ratios associated with 50% reduction in top growth followed the order: triticales > tolerant wheat > sensitive wheat > rye. Differences in mineral uptake associated with Al toxicity in wheat were more indicative of differential Al sensitivity in wheat than in triticale and rye which have higher internal Al tolerance.  相似文献   

16.
Barley (Hordeum vulgare L.) is a cereal grown for animal feed, human consumption, and malting. Nutrient concentrations are important as they provide information regarding the dietary values of barley consumed by animals or human beings. In addition, grain nutrient removal may be useful for refining fertilizer recommendations. A study was conducted in 2015 and 2016 investigating the cultivar effects on grain yield, quality, and grain nutrient concentrations and removal under irrigated conditions for two-row barley cultivars. Adjunct and feed cultivars produced the highest yields compared with the all-malt and food cultivars. Specific quality and nutrient values were greater than or equal to in the food cultivar compared to the malt or feed cultivars. Variations in nutrient concentrations were measured among the adjunct and all-malt cultivars, which could potentially affect the malting and brewing qualities. Grain yield, quality, nutrient concentrations and nutrient removal varied among cultivars grown under identical environmental conditions, which may influence end-use.  相似文献   

17.
Abstract

Long‐term no‐tillage has profound effects on soil properties which can affect the availability of plant nutrient elements. The objectives were to study the effects of tillage and lime treatments on soil pH and extractable soil micronutrients where poultry litter was used as a nitrogen (N) source. Surface soil samples were taken in the spring and fall for two years from a long‐term tillage experiment that had been in place for nine years. There were two tillage treatments [conventional (CT) and no‐tillage (NT)] and six lime/ gypsum treatments (control, 8,960 kg gypsum ha‐1 every fourth year, 4,480 kg lime ha‐1 every fourth year, and three treatments of 8,960 kg lime ha‐1 in a four‐year period divided by application times into 1, 2, and 4 treatments per year). Poultry litter was applied each year of the two‐year experiment at a rate of 8.96 Mg ha‐1 on a dry weight basis. The crop was corn (Zea maize L.). Soil samples were analyzed for pH and Mehlich‐1 zinc (Zn), manganese (Mn), and copper (Cu). Soil pH was higher for NT than CT and was higher in the spring than in the fall. Lime rates resulted in soil pH increases, but showed less difference for CT than NT. The three 8,960 kg ha‐1 per four yr treatments caused an interaction in that for CT the pH increased more for 2,240 kg ha‐1each year than for 8,960 kg ha‐1 every fourth year and the opposite was true for NT. Extractable Zn, Mn, and Cu all responded to this interaction being lower for the higher pH plots. Extractable Zn was higher for NT possibly due to high Zn from the poultry litter and non‐incorporation for NT. Extractable Cu was lower for NT as expected from the soil pH, whereas extractable Mn was not affected by tillage. Extractable Zn and Cu both increased over time due to inputs from the poultry litter. Neither extractable Zn nor Mn responded to increasing lime rates, however Cu decreased with increasing lime rate. Extractable Cu was influenced mainly by soil pH differences due to tillage and lime. Extractable Zn was influenced much more by tillage and from inputs by the poultry litter and not as much by pH differences. Extractable Mn was the least responsive to tillage and lime treatments of the three micronutrients studied.  相似文献   

18.
Abstract

The phytotoxicity of five nonessential elements (Co, V, Ti, Ag, Cr) to higher plants was studied in solution culture experiments with bush beans (Phaseolus vulgaris L. C.V. Improved Tendergreen). All, but in varying degrees, tended to concentrate in roots with a decreasing gradient to stems and leaves. Cobalt was one of the more mobile of the five trace metals. Its toxicity was expressed as severe chlorosis; 43 (with 10‐5 M) and 142 (with 10‐4 M) μg Co/g dry weight in leaves resulted in severe chlorosis. Vanadium as 10‐4 M vanadate resulted in smaller plants but not in chlorosis. Leaf, stem, and root V, respectively, were 13, 8, and 881 μg/g dry weight. Titanium was somewhat mobile with considerable yield decrease at 10‐4 M; leaf, stem, and root Ti concentrations, respectively, were 202, 48, and 2420 μg/g. Symptoms were chlorosis, necrotic spots on leaves, and stunting. Silver was very lethal at 10‐4 M AgNO3; at 10‐5 M yields were greatly decreased, but plants were grown without symptoms. Leaf, stem, and root concentrations of Ag for this treatment, respectively, were 5.8, 5.1, and 1760 μg/g dry weight. Plants grown with 10‐5 N Cr2O7 were decreased in yield by about 25% with or without EDTA (ethylenediamine tetraacetic acid) while the same level of Cr2(SO4)3 was essentially without effect. For the two salts, the leaf, stem, root concentrations for Cr, respectively were 2.2 and 1.3, 0.7 and 0. 7, and 140 and 104 μg/g. Most of the trace metals studied here had interactions in the uptake and/or distribution of other elements.  相似文献   

19.
20.
The effects of cooking, roasting, and fermentation on the composition and protein properties of grain legumes and the characteristics of dough and bread incorporated with legume flours were determined to identify an appropriate pretreatment. Oligosaccharide content of legumes was reduced by 76.2–96.9% by fermentation, 44.0–64.0% by roasting, and 28.4–70.1% by cooking. Cooking and roasting decreased protein solubility but improved in vitro protein digestibility. Mixograph absorption of wheat and legume flour blends increased from 50–52% for raw legumes to 68–76, 62–64, and 74–80% for cooked, roasted, and fermented ones, respectively. Bread dough with cooked or roasted legume flour was less sticky than that with raw or fermented legume flour. Loaf volume of bread baked from wheat and raw or roasted legume flour blends with or without gluten addition was consistently highest for chickpeas, less for peas and lentils, and lowest for soybeans. Roasted legume flour exhibited more appealing aroma and greater loaf volume of bread than cooked legume flour, and it appears to be the most appropriate preprocessing method for incorporation into bread.  相似文献   

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