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能源草是一种良好的生物质资源。为分析其在边际土地上的应用前景,在京郊挖沙废弃地上开展了柳枝稷(Panicum virgatum L.)与芦竹(Arundo donax L.)两种能源草的规模化种植,并从生物质产量和生态经济价值角度研究了其生产潜力。在京郊挖沙废弃地上,两种能源草均能获得较高的生物质产量,分别为3.77、 11.45 t·hm-2;从固定二氧化碳、释放氧气、吸收二氧化硫、滞降粉尘4个...
通过野外调查及定位研究,探讨了松嫩平原羊草草地盐碱化发生原因和过程,论证了羊草草地盐碱化过程的土壤“干扰-裸露”假说.松嫩平原羊草草地表层土壤(0～30 cm)盐分含量低,表层以下土壤层盐分含量高, 定义此为土壤盐渍化草地；土壤表层盐分含量增多的过程称为羊草草地盐碱化过程,盐碱化后形成的草地为盐碱化草地或盐生植物群落.羊草草地表层土壤盐分增多的主导原因是原初含盐量低的土壤表层被干扰消失,表层以下富...
新疆典型草原土壤腐殖酸组分的变化规律
土壤 复合体 游离腐殖酸 分布规律
2013/9/6
以新疆典型草原黑钙土、栗钙土和棕漠土为对象,研究了3种土壤不同土层腐殖质矿物复合体组分及其垂直分布规律。结果表明:13种典型草原土壤腐殖质总碳量的顺序为黑钙土(35、46g/kg)、栗钙土(31.30g/kg)和棕漠土(0.68g/kg);23种草原土壤都是以胡敏素(HM)含量最高,黑钙土、栗钙土和棕漠土的含量分别为68.17%、65.47%和42.81%;3按照腐殖酸类型分析,黑钙土和栗钙土是以...
引入循环采样方法,在生长季(7月初、7月末和8月末)测量了典型草原植被生物量和叶面积指数,并利用地统计方法分析了二者的空间分布格局.结果表明： 在7月初、7月末和8月末3个时期，地上生物量递增，叶面积指数（LAI）先增大后减小，地上生物量和LAI均具有良好的空间自相关性,二者空间格局相似且具有相似的时间演变规律,由条带状逐渐变为斑块状.从7月初到8月末，地上生物量和LAI的块金值/基台值［C0/（...
Purslane and natural vegetation as bioremediation tools to cope salinity in Satsuma mandarin orchards
Bioremediation natural vegetation purslane
2011/1/13
The objective of this study is to compare the Na and Cl removal capacity of natural vegetation (spontaneous flora) and cultivated purslane, as bioremediation techniques to overcome salinity in Satsuma...
Halogen chemistry of borehole water used in drinking troughs on game ranches in the Musina area, Limpopo Province, South Africa
Animal health hazard borehole water bromine chlorine fluorine iodine
2011/1/13
This study was initiated due to recent complaints of game farmers in the Musina area, Limpopo Province, South Africa regarding suspicious borehole water quality. Water samples obtained from 36 drinkin...
Effects of Exogenous Enzymes on Ruminal Fermentation and Degradability of Alfalfa Hay and Rice Straw
Alfalfa Rice Straw Ruminal Digestion Enzyme Additives
2016/5/5
This study was conducted to evaluate the use of exogenous enzymes as a potential means of improving the ruminal digestion (i.e., degradability) of alfalfa hay and rice straw. Twenty six enzyme-additiv...
Effects of Treating Whole-plant or Chopped Rice Straw Silage with Different Levels of Lactic Acid Bacteria on Silage Fermentation and Nutritive Value for Lactating Holsteins
Whole-plant Rice Straw Lactic Acid Bacteria Chopping Process Silage Quality Performance Holstein
2016/5/5
Two experiments were carried out to investigate i) the effects of four levels of lactic acid bacteria inoculants (LAB; 0, 2×105, 3×105 and 4×105 cfu/g fresh forage) and two physical forms of rice stra...
Evaluation of Chemical Composition and In vitro Digestibility of Appennine Pasture Plants Using Yak (Bos grunniens) Rumen Fluid or Faecal Extract as Inoculum Source
Yak Pasture Quality Faecal Extract In vitro Digestibility
2016/5/5
Pastures of the Apennines of Central Italy contribute to feed resources of high altitude (above 1,300 m sea level) grazing systems. The objective of this study was to evaluate the effectiveness of fae...
Comparison of Milk-clotting Activity of Proteinase Produced by Bacillus Subtilis var, natto and Rhizopus oligosporus with Commercial Rennet
Microbial Rennet Milk Clotting Bacillus subtilis Rhizopus oligosporus Purification
2016/5/5
This study investigated purification and milk-clotting activity of the enzymes produced by Bacillus subtilis var, natto and Rhizopus oligosporus compared with that of commercial rennet. The clotting t...
Chemical Composition of Selected Forages and Spices and the Effect of These Spices on In vitro Rumen Degradability of Some Forages
Spices Low Quality Forages Nutritive Value In vitro Degradability Ruminant
2016/5/5
Spices can be used as novel supplements to enhance the utilization of low quality forages (LQF) and reduce nutrient wastage by ruminant animals. However, it is essential to characterize these spices a...
Interactive Effects of Nitrogen and Potassium Fertilization on Oxalate Content in Napiergrass (Pennisetum purpureum)
Napiergrass Oxalate Accumulation Fertilization Nitrogen Potassium
2016/5/4
Ingestion of forage containing a large quantity of soluble oxalate can result in calcium deficiency and even death of livestock. Fertilization is one of the most practical and effective ways to improv...
Methane Emissions from Dry Cows Fed Grass or Legume Silage
Methane Emission Cow Silage Timothy Italian Ryegrass Red Clover
2016/5/4
Using an open-circuit system, we compared the methane (CH4) emission from dry cows fed first-cut Timothy silage (1st TY), second-cut Timothy silage (2nd TY), second-cut Italian ryegrass silage (2nd IR...
Impact of Particle Length of Alfalfa Hay in the Diet of Growing Lambs on Performance, Digestion and Carcass Characteristics
Particle Length Alfalfa Hay Lambs Intake Digestibility Carcass
2016/5/4
Thirty-six Najdi ram lambs, weighing an average of 24 kg and circa 3 months old, were utilized in this trial to evaluate the effects of various alfalfa hay particle lengths in the diet on growth perfo...