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1.
繁峙县域杂草名录   总被引:3,自引:0,他引:3  
自 198 2年以来 ,我们采集鉴定了该县域内的杂草标本 5 0 0多份 ,分属 63科 45 0种 ,其中山西省新纪录有10种 ,分属在 6科 (用 号表示新记录种 )。  相似文献   
2.
20世纪70年代末期,我国青藏高原的香日德镇出现了春小麦单产15195.00kg/hm2的高产纪录,生长季的光能利用率高达5.9%。其高光效原因何在以及能否保持不衰为众人所关注。近年笔者实地考察发现,生态技术创新是该区春小麦高产不衰的主导致因。其中特殊生态位新品种的成功选育、生态技术的全方位应用以及农田之外生态用地的有效建设是支持高产并可持续发展的三大支柱。生态技术进步作为经济增长的内在变量具有重要现实意义,香日德为生态经济学中的生态创新理论与B模式提供了成功实例。  相似文献   
3.
A study was conducted to estimate the record keeping, genetic selection, educational, and farm management effects on average milk yield per cow (AYC), milk fat percentage, bacterial score, and bulk tank somatic cell count (BTSCC) of dairy farms in the central region of Thailand. Farms were located in the provinces of Saraburi and Nakhon Ratchisima and were members of the Muaklek dairy cooperative. Records from individual animals were unavailable. Thus, farm records of milk yield, milk fat percentage, bacterial score, and BTCCC were collected from July 1, 2003 through June 30, 2006. Additional record keeping, genetic selection, education, and farm management information was collected through a questionnaire in May of 2006. Data from the Muaklek dairy cooperative and the questionnaire were then merged by a farm identification number. A single trait mixed model was used to analyze AYC, milk fat percentage, and BTSCC, while a log linear model was used to analyze bacterial score. Results showed that farms that kept records on individual animals had higher (P < 0.05) milk fat percentages and lower bacterial scores than farms that did not. Farms that used genetic information (EBV) and phenotypes when selecting sires were higher (P < 0.05) for milk fat percentage than farms that used only phenotypes and personal opinion. Farms milking cows with a single unit milking machine and by hand, had higher (P < 0.05) bacterial scores and BTSCC than farms using only a single or multi unit machine. Overall farms that kept individual animal records, used EBV when selecting sires, used a single method for collecting milk, and used family labor achieved higher performance from their herds than farms that did not.  相似文献   
4.
在统计2011—2014年汉中市地质灾害气象风险预警产品、检验质量、跟踪服务效果的基础上,探讨定量评估地质灾害气象风险预警服务的方法,提取预报准确率、预报服务覆盖率、预报服务时效、可能预防能力4个评估因子建立评估模型。通过实例评估,得出汉中市气象灾害风险预警服务效益评估为72%,说明风险预警准确率和服务时效是提高地质灾害气象风险预警服务水平的两项重要指标。  相似文献   
5.
We examined runoff and sediment transport associated with large-scale construction projects in Fujian Province, China. Six experimental plots, comprised of four plot types, were designed to mimic typical conditions immediately following disturbance. It was found that natural vegetative cover reduces both runoff and erosion by approximately 36 and 7457 times over bare ground, and 16 and 1801 times over typically planted grasses, respectively. The increase in erosion associated with the replacement of native vegetation with bare ground or grasses due to large-scale infrastructure projects in Fujian from 1999 to 2004, amounted to an estimated loss of 1.76 × 107 tonnes of top soil and 3.04 × 108 m3 of surface runoff from the province during the bare soil construction phase, and an additional 4.25 × 106 tonnes of top soil and 1.35 × 108 m3 of surface runoff from the province associated with the first year of operation for each project. This has implications for frequency and occurrence of landslides and other geographic hazards, the transport of chemicals into waterways, the transport of goods through shipping passages, and the fertility of land in Fujian.  相似文献   
6.
Summary Three crisping potato cultivars, Record, Saturna and Hermes, were stored at 5 or 10°C in gas mixtures of either 0.5% CO2 and 21.0% O2 (control) or 9.4, 6.4, 3.6 or 0.4% CO2 all combined with 3.6% O2. There was almost complete sprout inhibition, low weight loss and maintenance of a healthy skin for all cultivars stored in 9.4% CO2 with 3.6% O2 at 5°C for 25 weeks. When tubers from this treatment were stored for a further 20 weeks in air at 5°C the skin remained healthy and they did not sprout. The fry colour of crisps made from these potatoes was darker than the industry standard but when they were reconditioned, tubers of cv. Saturna produced crisps of an acceptable fry colour while crisps from the other two cultivars remained too dark. Reducing sugar levels were related to fry colour both after storage and after reconditioning. The other gas combinations and the controls did not have the same effect on sprouting and none of the controlled atmosphere treatments controlled sprouting at 10°C.  相似文献   
7.
This study examined the 130 current full-text titles in the BioOne.1 and BioOne.2 collections to determine whether they are peer-reviewed, contain book reviews, and are supplied by document delivery vendors. We identified indexing coverage in 11 major databases in agriculture and life sciences: Aquatic Sciences and Fisheries Abstracts (ASFA), AGRICOLA, Biological Abstracts, BIOSIS Previews, CAB Abstracts, Current Contents, Environmental Sciences and Pollution Abstracts, GeoRef, Scopus, ISI Web of Science, and Zoological Record. We concluded that the majority of the titles in BioOne collections are refereed and scholarly, indexed in several of the major indexing and abstracting journals in the field of agriculture and life sciences, and available via several major document delivery vendors. We find both BioOne collections to be valuable, useful, cost-effective journal aggregations.  相似文献   
8.
Summary After three weeks curing at 10°C, potato tubers cv. Record were stored at 4°C under different controlled atmospheres (CA) for six months to study the effect on crisp fry colour, sprout growth and rotting. Combinations of low levels of CO2 (0.7–1.8%) and low levels of O2 (2.1–3.9%) gave a significantly lighter crisp colour, low sprout growth and fewer rotted tubers compared with 0.9% CO2 and 21.0% O2. Tubers stored in these conditions. showed a significantly higher weight loss and shrinkage after reconditioning. High CO2: low O2 combinations during storage completely inhibited sprout growth and caused the darkest crisp colour, but after reconditioning tubers gave the same level of sprouting and crisps as light as the other CA combinations. Furthermore these combinations, especially CO2 at 10 or 15%, increased the onset of rotting. Also our results showed that at low concentrations of CO2 (0.7–1.6%), and low O2 (2–2.4%) there was an increase in tuber rotting.  相似文献   
9.
浙江省及邻近地区名茶形成的土壤地质环境分析   总被引:11,自引:1,他引:10  
名茶产地的成土母质主要有石英砂岩、花岗岩、酸性凝灰岩与片麻岩等 ,它们在浙江被两条地质深大断裂分隔为三区 ,而各区的母质又各有特点。从新构造运动看 ,名茶多分布在强烈上升的山地区和沿海的升沉过渡丘陵区。从局部环境看 ,名茶产地附近多有湖、海等巨大水体。各类成土母质对茶品质的影响可用地球化学性质来解释 ,有关的元素有Si、K、Fe、Al、Ca、Mg、Mn等。文中还从已发现的名茶产地地质学规律出发 ,提出了全省的名茶发展战略  相似文献   
10.
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