砂垫层基础的设计与施工措施     

田世滨  陈嘉未 《林业科技情报》2001,33(1):27-27

在各类工程中砂垫层的作用不同,作者对软弱地基在结构设计中采用砂垫层这一措施进行了详细叙述。  相似文献   

湟源县草地资源基本特点及开发利用     

殷咸芳  刘志林 《青海草业》2001,10(4):21-22,15

湟源县草地面积有 85 1 85 .1 3hm2 ,占全县土地总面积的 5 6.45 % ,草地资源丰富 ,牧草种类较多 ,农业生产秸秆来源广泛 ,但由于利用不当 ,造成了草地严重破坏和秸秆的浪费 ,如何合理利用草地和秸秆资源 ,扼制草地退化 ,是促进该县畜牧业发展的重要因素  相似文献   

以花生为主体作物的立体种植高效农业配置     

宫君秋 《中国油料作物学报》1994,(1)

以覆膜花生为优势布局的小麦  相似文献   

生化处理对玉米秸颗粒饲料营养价值的影响研究     

蒋林树 陈斌王晓霞  吴跃明闰伟杰 刘建新 《饲料与畜牧》2004,(1):18-20

以玉米秸秆为主要原料，通过添加不同比例的化学处理剂和营养强化剂，调制出5种玉米秸颗粒。对照组由玉米秸添加2％膨润土调制而成；试验组分别为：添加化学处理剂(石灰 尿素，以玉米秸DM计)4 0％(处理Ⅰ)、0 4％(处理Ⅱ)、2 2％(处理Ⅲ)和2 2％(处理Ⅳ)，同时在处理Ⅳ中再添加4％营养强化剂。采用Menke的人工瘤胃产气法评定不同玉米秸处理的体外消化率和营养价值。结果表明，处理Ⅱ、Ⅲ、Ⅳ的粗蛋白质含量明显高于处理Ⅰ和对照；处理Ⅰ、Ⅳ的NDF含量比对照分别降低了7、12％；各处理的ADF含量均比对照组明显降低，并以处理Ⅳ的下降幅度最大，达31．1％。各处理的体外产气量和产气速度均高于对照组，其中以处理Ⅳ的产气速度最快，其快速产气量(a)略高于对照，b的产气速度常数c比对照提高19．3％。相应地，处理Ⅱ、Ⅲ、Ⅳ的估测有机物消化率(OMD)均比对照有明显提高，其中处理Ⅳ的OMD最高，其次为处理Ⅱ，分别比对照(46％)提高19、13％，但处理Ⅰ无明显效应。表明用4％尿素处理可以明显改善玉米秸处理的化学组成和有机物质消化率，其效果优于2％石灰 2％尿素或单纯石灰处理，若将化学处理与营养强化剂结合使用，则可获得更好的处理效果。  相似文献   

暖卫工程施工质量通病的发生与防治     

段长毅  何军  冉宪文 《林业科技情报》2001,33(2):51-51

本文论述了暖卫工程跑、冒、滴、漏、堵等五大质量通病的发生原因及防治方法建议等。  相似文献   

在桩基础设计中两种规范的差异比较--《建筑地基基础设计规范》与《建筑桩基技术规范》     

林青  严滨 《林业科技情报》2004,36(4):14-15

通过对二部规范的对比，阐明“地基基础”与“桩基”相比在桩基础设计中作了较大的调整，这样既节省了工程造价又提高了桩基础设计质量。  相似文献   

覆盖免耕在休闲期的节水和生育期的调温效应   总被引：10，自引：2，他引：8  

姚宝林  景明  施炯林 《甘肃农业大学学报》2005,40(2):208-211

对免耕覆盖、秸秆还田和常规耕作在休闲期的节水效果研究表明:在夏季休闲期,免耕覆盖比常规耕作多贮水30.62mm,比秸秆还田多23.91mm;在冬季储水灌溉期间,可将储水定额从2100m3/hm2减少到600和975m3/hm2。对春小麦生育期土壤表层,5、10、15、20和25cm处温度变化观测发现:免耕覆盖土壤温度在气温较低的8:00可以提高土壤表层温度,在气温较高的14:00可以减缓土壤温度的升高,而在19:00气温降低时可以减缓土壤温度的降低,使土壤温度一直保持在一个稳定的状态,这有利于调节农田小气候,创造作物良好的生长环境。  相似文献   

草菇栽培原料发酵剂菌株的筛选及应用初探     

黄福常  覃培升  韦玉高  冯威梦 《中国食用菌》2005,24(2):21-25

从广西军区食用菌生产基地、广西大学微生物厂、广西大学牧场等地采集的样品中分离得到多株菌株。再从耐热、耐碱、产酶能力及营养物综合利用等方面考查各菌株，最终筛选得到理想的放线菌1株、细菌3株组成发酵剂菌株，并用于栽培原料发酵后栽培草菇。实验结果显示：加入该菌剂的料堆27h后温度可升至65℃，此时对照55℃，环境40℃，草菇生物学效率比对照提高了4.76％至7．56％。  相似文献   

Effects of weed control practices on surface-dwelling arthropod predators in tomato agroecosystems     

Yardım  Erdal N.  Edwards  Clive A. 《Phytoparasitica》2002,30(4):379-386

Weed control, an important practice in agroecosystems to protect crop production, is usually achieved with herbicides. However, these pesticides are expensive, pose potential risks to the environment, may affect some beneficial organisms indirectly, and decrease overall arthropod biodiversity, including pests and their natural enemies, by removing weeds that might act as hosts or shelters for many organisms. The activity density response of important surface-dwelling arthropod predators (ground beetles [Coleoptera: Carabidae], ants [Hymenoptera: Formicidae] and spiders [Arachnida: Araneae]) to herbicides (trifluralin and paraquat), and to two alternative weed management practices (rye straw mulch and mechanical treatment to maintain weeds below threshold levels, in comparison with an untreated check), was assessed using pitfall traps. The mulch treatment had the greatest effect on activity density, reducing the number of predators trapped significantly (P<0.05). Herbicide use resulted in significant (P<0.05) reductions in the activity density of ground beetles. Most predators were trapped in the check plots — which had the highest weed biomass, followed in turn by numbers trapped in the threshold weed control treatment, the full herbicide application and the mulch treatment plots. http://www.phytoparasitica.org posting July 10, 2002.  相似文献   

Spatial distribution of Lolium rigidum seedlings following seed dispersal by combine harvesters     

J M Blanco-Moreno  L Chamorro  R M Masalles  J Recasens†  & F X Sans 《Weed Research》2004,44(5):375-387

This paper considers the relationships between the dispersal of seeds and the distribution pattern of an annual weed. A comparative study of seed dispersal by combine harvesters, with and without a straw chopper attached, was established using Lolium rigidum, a common weed in Mediterranean cereal crops. Seed dispersal distance was quantified and the relationships between dispersal and fine‐scale seedling distribution evaluated. Primary dispersal of L. rigidum seeds occurs in a very limited space around the parent plants, but the density of seed is low because most seeds do not fall from spikes spontaneously. In contrast, many seeds are spread by combine harvesters. In this study the maximum dispersal exceeded 18 m from established stands in cereal fields, although the modal distance was close to the origin. In addition, the action of the combine harvesters tended to accumulate L. rigidum seeds predominantly under the straw swath, with some lateral movement. This action could explain the fine‐scale banded pattern of L. rigidum in cereal fields. Although the treatment of straw by the standard and straw chopper combines differed, the resultant seed distribution showed few differences.  相似文献