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71.
在含白糖、石膏各1%,分别以桑枝粒,桑枝屑和蚕沙为基础,加与不加麦麸,或以蚕沙代替麦麸的不同8种菌种培养基上培养,除加入0.5%尿素的明显表现不良影响外,其余均能正常生长,尤以在蚕沙培养基中生长最快。表明蚕沙可以代替麦麸使用。桑枝屑袋栽毛木耳,一潮耳片的生物学效率为47.8%~60.8%。凤尾菇在含10%麦麸桑枝培养基上的生物学效率是64.2%,在100%桑枝屑是58.8%,在含桑枝屑30%、桑枝粒 70%是58.2%,在含稻草 60%与40%的桑枝屑生料袋栽时生物学效率分别是43.3%与31.7%,表明加入稻草混合反而效果不好。 相似文献
72.
用6种不同的贮藏方法进行果蔗常温保鲜试验,结果发现垫盖塑料薄膜的平行堆蔗处理能使贮藏环境维持较高的相对湿度,降低日最高温度,有利于防病保鲜,贮藏70天后仅干耗13.60%,此对照低208.82%,好蔗率达92.0%(对照全部坏变),且尚能保持一定的蔗汁锤度,清甜可口。 相似文献
73.
菜心对邻苯二甲酸酯(PAEs)吸收途径的初步研究 总被引:16,自引:2,他引:16
采用玻璃室处理和污染土壤覆盖原土壤来控制PAEs来源进行盆栽试验,应用GC/MS联机检测技术初步研究了菜心对PAEs的吸收途径。结果表明:污染土壤处理与污染土壤上覆盖原土壤处理相比,前者菜心茎叶中DBP和DEHP的含量均高于后者,但相差不大,表明菜心茎叶可以吸收污染土壤中挥发出来的DBP和DEHP,而根系吸收运移是菜心茎叶中DBP和DEHP的主要来源途径。玻璃室处理增加了菜心茎叶和根系中DBP的含量,而对DEHP的影响趋势不明显。DBP与DEHP相比,前者更易被菜心根系吸收并向地上部(茎叶)运移,后者主要滞留在根部。 相似文献
74.
在3个甘蔗品种的分蘖初期,分别喷施硝酸镧和混合稀土溶液,结果这两种处理都能促使甘蔗叶片在不同生长期的多酚氧化酶活性极显著高于喷清水的对照,而且喷施混合稀土的又极显著高于硝酸镧处理。混合稀土还能使即将进入工艺成熟期的甘蔗叶片的过氧化物酶活性高于对照。 相似文献
75.
莫天砚 《广西农业生物科学》1991,(3)
本文报道有关草菇厚垣孢子形成的条件.其中,营养丰歉状况直接地影响孢子产生的迟早与数量,磷、镁的存在,弱酸性条件和30~35℃温度范围有利于孢子的产生。 相似文献
76.
Methane emissions from different vegetation zones in a Qinghai-Tibetan Plateau wetland 总被引:1,自引:0,他引:1
Mitsuru Hirota Yanhong Tang Shigeki Hirata Wenhong Mo Shigeru Mariko 《Soil biology & biochemistry》2004,36(5):737-748
We measured methane (CH4) emissions in the Luanhaizi wetland, a typical alpine wetland on the Qinghai-Tibetan Plateau, China, during the plant growth season (early July to mid-September) in 2002. Our aim was to quantify the spatial and temporal variation of CH4 flux and to elucidate key factors in this variation. Static chamber measurements of CH4 flux were made in four vegetation zones along a gradient of water depth. There were three emergent-plant zones (Hippuris-dominated; Scirpus-dominated; and Carex-dominated) and one submerged-plant zone (Potamogeton-dominated). The smallest CH4 flux (seasonal mean=33.1 mg CH4 m−2 d−1) was observed in the Potamogeton-dominated zone, which occupied about 74% of the total area of the wetland. The greatest CH4 flux (seasonal mean=214 mg CH4 m−2 d−1) was observed in the Hippuris-dominated zone, in the second-deepest water area. CH4 flux from three zones (excluding the Carex-dominated zone) showed a marked diurnal change and decreased dramatically under dark conditions. Light intensity had a major influence on the temporal variation in CH4 flux, at least in three of the zones. Methane fluxes from all zones increased during the growing season with increasing aboveground biomass. CH4 flux from the Scirpus-dominated zone was significantly lower than in the other emergent-plant zones despite the large biomass, because the root and rhizome intake ports for CH4 transport in the dominant species were distributed in shallower and more oxidative soil than occupied in the other zones. Spatial and temporal variation in CH4 flux from the alpine wetland was determined by the vegetation zone. Among the dominant species in each zone, there were variations in the density and biomass of shoots, gas-transport system, and root-rhizome architecture. The CH4 flux from a typical alpine wetland on the Qinghai-Tibetan Plateau was as high as those of other boreal and alpine wetlands. 相似文献
77.
78.
Weidong Cheng Xueqing Xing Dehong Wang Kunhao Zhang Quan Cai Guang Mo Zhongjun Chen Zhonghua Wu 《Journal of Wood Science》2011,57(6):470-478
Wood is a highly sophisticated and multihierarchical material. The nanoscale structures in natural cell walls of red pine,
American pine, and white ash specimens were investigated using the small-angle X-ray scattering (SAXS) technique. A tangent-by-tangent
method was used to analyze the SAXS data. The results demonstrate that the multihierarchical scatterers in the three specimens
can be divided into two dominant components, i.e., a sharp component and a wide component. The sharp component mainly corresponds
to the contribution of cellulose microfibrils, and its size is almost unaffected by the water content. However, the wide component
includes voids or microcracks and cellulose microfibril aggregates; its size changes, reflecting swelling and water accumulation
in the voids or microcracks. Because of the different morphological features of the cell walls, softwood (red pine and American
pine) displays different tendencies from hardwood (white ash) in terms of changes in the wide component with water content:
the average scatterer size of the wide component has an incremental tendency with the water content in softwood, but it has
a descending tendency in hardwood. Fractal analysis further revealed that in white ash the surface of scatterers is coarser
and the scatterers form more compact nanostructures than in the two pine woods. All this nanostructural information can be
used to explain well the difference of swelling behaviors between the two pines and the white ash. 相似文献
79.
城市污泥与玉米秸秆堆肥中多环芳烃(PAHs)的研究 总被引:12,自引:1,他引:12
将城市污泥与玉米秸秆进行自然通风堆肥处理,应用GC/MS检测方法对污泥堆肥中的多环芳烃化合物(PAHs)进行了分析。污泥堆肥中PAHs的含量较低,ΣPAHs和ΣPAHscarc分别为0.561 mg/kg和0.107 mg/kg,绝大部分PAHs化合物的含量低于0.050 mg/kg,含量较高的主要是中、低分子量的化合物。PAHs的降解效果显著,ΣPAHs和ΣPAHscarc的降解率在80%左右,绝大部分化合物的降解率在50%以上,中等分子量的3个和4个苯环的化合物的降解效果相对较好。污泥堆肥中PAHs的含量、分布模式及其降解效果与原污泥中PAHs的特征密切相关。 相似文献
80.
对广西浦北县红锥林保护区出产的主要商品红菇进行了调查,经组织分离获得了该种菇的纯培养。红菇需在高温高湿条件下生长,低温下保藏容易失活。红菇对培养基的营养有特殊的要求,其分解木质纤维素的能力较弱。 相似文献