砾石土壤施用保水剂的蓄水保墒技术研究

在极端干旱条件下,以成龄无核白葡萄为研究材料,采用滴灌灌水技术,研究了施用不同剂量保水剂下各处理土壤含水量与葡萄生理特性和光合特征以及对葡萄品质产量的影响。结果显示:各处理在0—100 cm土层中的土壤含水量对照处理明显低于保水剂处理;叶片水势在水前与水后的变化规律一致,均为B100最大,其次B200和B50,对照最小;各处理葡萄叶片蒸腾速率在葡萄果实膨大期逐渐升高,在果实成熟期快速下降,其中CK和B100蒸腾速率小而B200和B50略高;在光合速率上,B200明显高于其它3个处理,而B100最低,B50在颗粒成熟期高于B100和对照。对葡萄施用保水剂的经济评价中得出,B100处理虽然在葡萄产量上稍低于B200,但相比B200减少了一倍投资,使其最终获得了最大的收益。说明保水剂能明显提高土壤的水分利用效率,具有显著的蓄水保墒作用。     

植物抗逆剂蘸浆造林经济效益评价(Ⅰ) ——成本核算

正确评估药剂蘸浆造林成本是科学使用植物抗逆剂的前提。通过对异地试验跟踪调查,采用成本核算法,分析了药剂蘸浆造林各项成本变化。结果显示:对照区、纳米型植物抗逆剂和多效抗旱驱鼠剂(RPA)处理区油松蘸浆造林总成本依次为(7 077.45±404.84)元·hm^-2、(7 238.11±406.48)元·hm^-2和(7 242.20±386.21)元·hm^-2,侧柏为(5 435.10±394.83)元·hm^-2、(596.69±411.88)元·hm^-2和(5 635.57±422.21)元·hm^-2。与对照差异不显著; 而地区间、树种间和药剂间差异显著或极显著。油松和侧柏用工成本占总成本比重为58.37%±0.64%和80.00%±1.64%,种苗成本比重为39.60%±0.69%和17.97%±1.53%,树种间差异极显著; 用工和种苗成本是控制药剂蘸浆造林总成本的关键因素,可以通过提高机械造林和工厂化育苗程度降低造林成本。     

不同打叶数对烤烟综合性状的影响

试验以‘云烟85’为参试品种,研究随着打叶数量的逐渐增多,烤烟的综合性状所呈现的不同规律。结果表明,株高、节距、叶片长宽、单叶重均与打叶数成正相关,随着打叶数量的逐渐增加,茎围、产值、上等烟比例均呈现先升高后降低二次曲线的变化规律。综合分析认为,云南省广南县以打掉下部3片底脚叶和上部1片顶叶的处理,产量稳定,等级质量结构最优,产值最高。     

不同施肥模式对早稻经济性状、产量及经济效益的影响

为客观评价早稻测土配方施肥技术的效果,2008—2012年在江西省吉安市13个县（市、区）,以早稻品种为试验材料,在大田条件下设置测土配方施肥、常规施肥、空白不施肥3个处理,研究了施肥模式对早稻经济性状、产量及经济效益的影响。结果表明：在主要经济性状上,测土配方施肥处理比常规施肥处理和空白处理具有明显优势（空白处理区的结实率除外）;测土配方施肥处理产量最高,平均达到7020.2 kg/km2,比常规施肥处理和空白处理分别平均增产463.8 kg/km2、2723.8 kg/km2;测土配方施肥处理经济效益最好,平均达到13308.2元/km2,比常规施肥处理和空白处理分别平均增收849.6元/km2、4056.0元/km2。在本试验条件下,测土配方施肥模式为最佳施肥模式,更适合当地推广应用。     

葡萄籽粉替代玉米对成年母羊体重和经济效益的影响

本试验旨在研究日粮中添加不同剂量葡萄籽粉替代玉米对成年母羊体重和经济效益的影响。试验选取年龄相近(15~16月龄)、健康状况良好的成年母羊32只,根据体重相近原则随机分为4组,对照组饲喂基础日粮,试验Ⅰ、Ⅱ和Ⅲ组分别用葡萄籽粉替代基础日粮中7%、14%和21%玉米。结果表明,试验各组间羊增重差异不显著(P＞0.05),但试验Ⅰ组平均日增重比对照组提高了14.50%,且经济效益比对照组平均提高了37.74%。提示,本试验中在基础日粮中使用葡萄籽粉替代7%玉米对成年母羊的增重效果和经济效益最佳。     

华北驼绒藜替代不同比例粗饲料对苏尼特羊增重及经济效益的影响

试验将驼绒藜按不同精粗比配合成颗粒日粮饲喂苏尼特羊,对比分析驼绒藜日粮与苜蓿日粮、谷草日粮对羊增重的效果。结果表明,华北驼绒藜、苜蓿、谷草铡短粉碎与50%、30%精料混合制成颗粒日粮对绵羊体增重效果最好,日增重可达127 g/d;在荒漠草原区,苜蓿的高价格是限制其推广的主要原因;华北驼绒藜和谷草在30%精料水平下,与同精料水平条件下用苜蓿饲喂绵羊具有相同的增重效果,并可增加纯收入80元/只。     

Effect of vegetation on soil water retention and storage in a semi-arid alpine forest catchment

The runoff generated from mountainous regions is recognized as the main water source for inland river basins in arid environments. Thus, the mechanisms by which catchments retain water in soils are to be understood. The water storage capacity of soil depends on its depth and capacity to retain water under gravitational drainage and evapotranspiration. The latter can be studied through soil water retention curve (SWRC), which is closely related to soil properties such as texture, bulk density, porosity, soil organic carbon content, and so on. The present study represented SWRCs using HYDRUS-1D. In the present study, we measured physical and hydraulic properties of soil samples collected from Sabina przewalskii forest (south-facing slope with highest solar radiation), shrubs (west-facing slope with medium radiation), and Picea crassifolia forest (north-facing slope with lowest radiation), and analyzed the differences in soil water storage capacity of these soil samples. Soil water content of those three vegetation covers were also measured to validate the soil water storage capacity and to analyze the relationship between soil organic matter content and soil water content. Statistical analysis showed that different vegetation covers could lead to different soil bulk densities and differences in soil water retention on the three slope aspects. Sand content, porosity, and organic carbon content of the P. crassifolia forest were relatively greater compared with those of the S. przewalskii forest and shrubs. However, silt content and soil bulk density were relatively smaller than those in the S. przewalskii forest and shrubs. In addition, there was a significant linear positive relationship between averaged soil water content and soil organic matter content (P<0.0001). However, this relationship is not significant in the P. crassifolia forest. As depicted in the SWRCs, the water storage capacity of the soil was 39.14% and 37.38% higher in the P. crassifolia forest than in the S. przewalskii forest and shrubs, respectively, at a similar soil depth.     

我国循环农业发展研究

循环农业是一种低碳农业发展模式,是实现农业可持续发展的必由之路。阐述我国发展循环农业的必要性,提出发展循环农业的基本措施,介绍常见的生态循环农业模式及其效果,分析发展循环农业所取得的经济效益及生态效益。     

豚草对花生产量性状的影响及其经济阈值

为明确豚草( Ambrosia artemisiifolia )对花生生长和产量的影响及其经济阈值,采用添加系列试验和拟合函数关系模型的方法,研究了豚草与花生的竞争关系。结果表明,在豚草竞争干扰下,花生单株分枝数、荚果数、有效荚果数及产量均随豚草密度的增加而逐渐降低,而株高没有显著变化。指数模型能较好地拟合豚草对花生分枝数（y=7.307e-0.003x,P<0.001）的影响;对数函数模型能较好地拟合豚草密度与花生单株荚果数(y= -2.355lnx +16.325,P<0.001)、有效荚果数（y= -38.104㏑x+248.022,P<0.001）、花生产量（y= -1 172.945lnx+6 765.501,P<0.001）以及产量损失（y = 17.825lnx-2.866,P<0.001）间的关系。花生田豚草人工拔除的经济阈值为1.42株/m2,使用50%乙草胺乳油防除的经济阈值为1.22株/m2。     

再生稻各节位分蘖的抽穗期和经济性状观察

选用Ⅱ优623和天优3301品种,定株定蘖观察不同节位再生分蘖的抽穗期和经济性状。结果表明,分蘖抽穗期随节位下移而推迟,每低一节平均推迟2～3 d,二次分蘖抽穗期比其母茎平均推迟12～14 d;分蘖萌发成穗率和结实率也随节位下移而降低;每穗粒数和千粒重以倒3分蘖最多,倒2分蘖次之,倒4、5分蘖再次之,二次分蘖显著减少;在头季成熟时高桩手割条件下,倒2、3分蘖合占再生季70%的穗数、80%的产量。研究结果为诊断各节位再生分蘖的生育进程和掌握调控时机提供了科学依据。