大城市近郊县域耕地保护预警方法   总被引：8，自引：2，他引：6  

赵婷婷  姜广辉  张凤荣  段增强  何玉凤  马素华  苗利梅 《农业工程学报》2010,26(1):335-340

县域是耕地保护及预警最为合理的研究尺度,综合应用土地利用规划、年度计划和农用地分等定级成果,预测耕地资源“量”与“质”的变化趋势是科学合理地保护耕地的有效手段。该文在单项指标和综合指标2个层次上,从耕地数量、稳定生产能力、易变养分的空间变化和综合4个方面构建了县域耕地保护预警体系,并对北京市顺义区进行了耕地保护预警研究。顺义区耕地保护单项指标预警结果表明,2007、2008年顺义区耕地数量出现轻警,2009、2010年则为无警;耕地稳定生产能力在2007、2009年为中警,2008年为重警,2010年为轻警;而易变养分含量变化的警情则不尽相同。综合指标预警结果表明：2007年顺义区耕地保护出现重警,2008年和2009年为中警,2010年为轻警。研究结果从预警的时间尺度和空间尺度出发,全面考虑了耕地的数量变化和质量变化,并使警情判定与土地管理和农业生产工作相衔接,是进行区域耕地保护预警研究的有效方法。  相似文献   

Influence of solar drying and storage conditions on microstructure,crack propagation and nano-hardness of paddy and wheat     

《Journal of Cereal Science》2020

The influence of hybrid solar drying (HSD) and storage conditions on microstructure, crack propagation, nano-hardness and milling indices of paddy and wheat grains were investigated. Milling yield and head rice yield of dried paddy was 71.48% and 72.42%, which was further increased by 1–1.26% and 3.12–4.65%, respectively. Flour yield from dried wheat was found to be 77.30% and was reduced by 3.5–7.7% after 180 days of storage. Maximum nano-hardness of 0.15 ± 0.02 GPa was obtained for rice stored at 5 °C, whereas, for wheat, nano-hardness, elastic modulus, and peak load values gradually reduced with a storage time of 180 days. Micro-X ray computed tomography images revealed the pore size of paddy and wheat samples to be in the range of 0.01–0.8 mm³. Micrographs showed a compact paddy surface, whereas wheat endosperm witnessed cell disruption and agglomeration.  相似文献   

鹿胎制剂对老年雌性大鼠免疫指标的影响     

赵国财  苏禹刚 《畜牧与饲料科学》2014,(1):29-30

以老年雌性Wister大鼠为研究对象,研究在正常饮水中添加不同鹿胎制剂对老年雌性大鼠免疫指标的影响。结果表明,在日粮中添加鹿胎制剂可以显著提高老年雌性大鼠血清中总蛋白含量,增强老年雌性大鼠机体免疫力,其中以组方二(鹿胎粉、人参、党参、蜂花粉)效果最佳。  相似文献   

碱胁迫对甜瓜幼苗生长及光合色素含量和抗氧化作用的影响     

吴旭红  董雪芹 《种子》2011,30(8)

采用砂培法在人工气候箱控制条件下,研究了碱胁迫(0、15.0、30.0、45.0、60.0 mmol/L Na2 C03)对2种甜瓜(鹤丰7号和超级五龙白)幼苗生长及光合色素含量和抗氧化作用的影响.结果表明,2种甜瓜耐碱的极限浓度为60.0 mmol/L.低浓度(15.0 mmol/L)碱胁迫,甜瓜幼苗地上、地下部分干、鲜重和根冠比(鲜)增加,幼苗生长状况良好.随培养液中碱浓度的升高,甜瓜幼苗叶绿体色素含量及上述各项指标逐渐下降,抗氧化酶活性呈先升后降的趋势.超级五龙白随碱胁迫加剧,POD活性升幅较缓而CAT活性降幅较大；鹤丰7号Chla、car含量和保护酶系统的稳定性高于超级五龙白,具较强的碱耐受性.  相似文献   

Nutrient uptake,nitrogen use efficiencies,and energy indices in soybean under various tillage systems with crop residue and nitrogen levels after combine harvested wheat     

《Journal of plant nutrition》2012,35(3):407-417

Abstract

A field study was conducted during kharif (rainy season) to study nutrient uptake, nitrogen use efficiencies, and energy indices in soybean under various tillage systems with crop residue and nitrogen levels after combine harvested wheat for two consecutive years. The treatments included three planting methods (Happy Seeder sowing, Straw Chopper?+?Zero Tillage sowing and Conventional sowing) and four nitrogen levels (0, 75, 100, and 125% recommended nitrogen). Nitrogen (N), phosphorus (P), and potassium (K) uptake by seed and straw were significantly higher in Happy Seeder sowing than Straw Chopper?+?Zero Tillage sowing and conventional sowing. Agronomic efficiency, physiological efficiency, and apparent recovery were not influenced significantly by different planting methods whereas partial factor productivity, energy output, net energy, energy use efficiency, and energy productivity were significantly higher in Happy Seeder sowing than Straw Chopper?+?Zero Tillage sowing and conventional sowing. N and P uptake by seed and straw increased significantly from 0 to 75 and 75 to 100% recommended N and similar trend was found in K uptake by seed and straw. Agronomic efficiency, apparent recovery and energy output were increased up to 100% recommended N. However, partial factor productivity was decreased significantly with increase in N levels and physiological efficiency was not influenced significantly by different N levels.  相似文献   

Alleviation of Multinutrient Deficiency for Productivity Enhancement of Rain-Fed Soybean and Finger Millet in the Semi-arid Region of India     

《Communications in Soil Science and Plant Analysis》2012,43(10):1427-1435

Soil nutrient contents were determined in 802 surface soil samples (0–15 cm deep) collected from farmers' fields that support extensive cultivation of soybean (Glycine max L.) and finger millet (Eleusine coracana G.), spread across three districts, in the semi-arid regions of Karnataka, India. Following soil analysis, on-farm crop trials were conducted during 2005–2007 to study the crop response to the soil application of nitrogen (N), phosphorus (P), sulfur (S), boron (B), and zinc (Zn) fertilizers. Analyses of soil samples revealed that 4–83% fields were deficient in N, 34–65% in P, 83–93% in extractable S, 53–96% in B, and 34–88% of farmers' fields were deficient in Zn. On-farm trials conducted during the three rainy seasons (2005, 2006, and 2007) significantly (P ≤ 0.05) enhanced crop productivity indices such as yields of grain, stover, and total biomass in soybean and finger millet crops. Integrated management of deficient nutrients in finger millet and soybean crops significantly enhanced the grain and straw uptake of N, P, K, S, and Zn.  相似文献   

壳寡糖对断奶仔猪免疫力及相关理化指标的影响     

党国旗  杨新宇  许晴  崔嘉  陈宝江 《动物营养学报》2017,29(11)

本试验旨在探讨壳寡糖对断奶仔猪免疫力及相关理化指标的影响。试验选用21日龄"杜长大"杂交断奶仔猪256头,随机分为4个组,每组4个重复,每个重复16头猪。对照组饲喂基础饲粮,试验组分别饲喂在基础饲粮中添加50、100和150 g/t壳寡糖的饲粮。预试期7 d,试验期28 d。结果表明:1)与对照组相比,试验1组、试验2组和试验3组血清谷草转氨酶活性分别降低了26.71%(P0.01)、7.56%(P0.05)和16.64%(P0.05),血清谷丙转氨酶活性分别降低了47.26%(P0.05)、47.28%(P0.01)和21.88%(P0.05),血清碱性磷酸酶活性分别提高了6.37%、16.78%和1.24%(P0.05);试验组血清总蛋白含量均高于对照组(P0.05)。2)与对照组相比,试验1组、试验2组和试验3组血清免疫球蛋白A含量分别提高了45.40%(P0.05)、2.62%(P0.05)和137.26%(P0.01);试验1组和试验2组血清免疫球蛋白G含量分别较对照组提高了4.47%和10.92%(P0.05),血清免疫球蛋白M含量分别比对照组提高了9.29%和5.69%(P0.05);与对照组相比,试验1组、试验2组和试验3组血清肿瘤坏死因子-α含量分别提高了51.76%(P0.01)、29.42%(P0.05)和88.29%(P0.01)。3)与对照组相比,试验组血清伪狂犬、猪瘟、蓝耳抗体效价均有不同程度提高,其中试验3组血清伪狂犬和蓝耳抗体效价显著高于对照组(P0.05)。由此可知,饲粮中添加适宜壳寡糖能一定程度提高断奶仔猪能体液免疫与细胞免疫能力以及血清抗体效价,缓解断奶应激。  相似文献   

补喂来曲唑对速步马运动性能、血浆抗氧化指标与激素水平及体重的影响     

马军  李晓斌  邓海峰  赵芳  杨开伦 《动物营养学报》2016,(8):2630-2638

本试验旨在探究补喂来曲唑对速步马运动性能、血浆抗氧化指标与激素水及体重的影响。选取平均年龄为2.5岁、平均体重为(398.16±25.34)kg的经过良好速步训练的伊犁马公马10匹,随机分为2组,分别为对照组和试验组,每组5匹。所有马匹每天每匹饲喂混合牧草10 kg、颗粒精料3 kg,在此基础上试验组马匹每天每匹补喂5 mg来曲唑,进行30 d的饲喂试验和训练试验。分别在试验第0天、第10天、第20天、第30天清晨空腹颈静脉采血,测定血浆中激素指标;在试验第0天和第30天早晨空腹称重,并进行1 000 m速步赛,分别在赛前1 h、赛后即刻、赛后20 min、赛后2 h颈部静脉采集血液,测定血液酸碱度相关指标和血浆抗氧化指标。结果显示:补喂来曲唑能够提高试验马匹1 000 m速步赛成绩;赛后2 h时,试验组马匹血浆中过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)活力,总抗氧化能力(T-AOC)及尿酸(UA)含量均高于对照组,其中GSH-Px活力、T-AOC分别达到极显著(P0.01)和显著水平(P0.05),而血浆中丙二醛(M DA)含量则显著低于对照组(P0.05)。就血液酸碱度相关指标而言,在赛后即刻、赛后20 min、赛后2 h试验组血液中碳酸盐(HCO-3)含量低于对照组(P0.05),而碱剩余(BEecf)、p H则高于对照组(P0.05)。试验第10天、第20天、第30天时试验组马匹血浆中睾酮(T)、雄烯二醇(AD)水平均高于对照组(P0.05)。此外,补喂来曲唑还可提高速步马体重。因此,给速步马补喂5 mg/(匹·d)来曲唑可缩短1000 m速步赛比赛用时,提高机体的抗氧化能力和酸碱缓冲能力,并使血浆中T和AD水平上升,同时增加速步马的体重。  相似文献   

冬小麦生长适宜动态指标的知识模型   总被引：9，自引：1，他引：9  

朱艳  曹卫星  周治国  田永超 《中国农业科学》2004,37(1):43-43

 在分析和提炼小麦栽培理论与技术最新研究资料的基础上 ,通过定量描述冬小麦生长发育动态与品种类型、生态环境和生产技术水平之间的动态关系 ,以基于生理发育时间的动态生长度日为主线 ,建立了系统化和广适性的冬小麦生长适宜动态指标的知识模型 ,可为不同环境条件和冬小麦品种栽培过程中的苗情诊断提供定量化的动态生长指标 ,包括主茎叶龄、叶面积指数、群体茎蘖数和干物质积累量等。利用不同地点的常年每日气象资料以及不同品种类型、不同产量目标和不同播期资料对所建知识模型进行了实例分析 ,表明知识模型对冬小麦生长适宜动态指标具有  相似文献   

芦荟粉对西伯利亚鲟生长和血液生化指标的影响   总被引：1，自引：0，他引：1       下载免费PDF全文

王常安  徐奇友  许红  朱青  郑秋珊  孙大江 《上海海洋大学学报》2011,20(4):541-545

以体重（23.5±3.6） g西伯利亚鲟（Acipenser baerii Brandt）为对象,研究芦荟粉对其生长和血液生化指标的影响。试验共分6个处理,处理G₁~G₅组芦荟粉的添加量分别为0、0.125%、0.250%、0.500%、1.000%,处理G₆组添加25 mg/kg大蒜素作为药物对照组。饲养期为56 d。试验结果表明,与G1和G6相比,饲料中添加芦荟粉对西伯利亚鲟增重率、特定生长率、饵料系数等无显著影响（P>0.05）;当饲料中芦荟粉的添加量为0.250%和0.500%时,血浆超氧化物岐化酶活力显著提高（P<0.05）;当饲料中芦荟粉的添加量为0.125%和0.250%时,血浆丙二醛含量显著降低（P<0.05）;饲料中添加0.250%~0.500%的芦荟粉可提高鱼体的抗氧化能力;饲料中添加芦荟粉对西伯利亚鲟血浆球蛋白、谷丙转氨酶活力、血糖、补体C3、补体C4、酸性磷酸酶活力、碱性磷酸酶活力等无显著影响（P>0.05）。  相似文献