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91.
92.
绵枣儿用于三峡库区植被重建及组织培养快繁研究 总被引:4,自引:0,他引:4
绵枣儿的淹水试验及组织培养结果表明:绵枣儿的成活率高、长势较好,适于库区植被重建;假鳞茎诱导愈伤组织较快,最佳培养基为6-BA 2.0 mg/L+NAA 0.3 mg/L;不定芽分化最适培养基为MS+6-BA 2.0 mg/L+NAA 0.3 mg/L。 相似文献
93.
Changes in vegetation and soil properties because of agricultural abandonment may affect soil nitrogen (N) and associated processes. We investigated soil N (total N: TN, inorganic N: NH4–N and NO3–N) and denitrification potential in cropland, pine plantations and abandoned agricultural land along a secondary succession sequence (grassland→shrubland→secondary forest) in a headwater catchment in the Qinling Mountains, northwest China. The results show that the soil denitrification potential differed significantly among the five land‐use types with the highest potential in the secondary forest, followed by grassland, shrubland, cropland and plantations. The denitrification potential of the 20‐ to 40‐cm layer was significantly lower compared with the topsoil (0–20 cm) across all land‐use types. TN, soil organic matter (SOM) and NH4–N increased significantly with stand age, whereas there was an opposite trend in soil pH. However, the denitrification potential did not relate to stand age in a linear manner. We conclude that changes in soil TN, SOM and pH during vegetation succession following agricultural abandonment are critical controls on the denitrification potential. 相似文献
94.
分析巴州区农业科技推广呈现推广机构多元化、推广方式多样化、推广载体多类化、服务形式多种化的基本特点,农业科技推广采取理顺管理体制、加强设施建设、强化岗位管理、加大投入力度、提高队伍素质的主要措施,存在农技推广经费不充足、农技人员结构不合理、服务对象覆盖不全面、社会推广组织不规范、绩效考核机制不健全的问题,提出了抓好两个宣讲、注重两个培育、理顺两个体制、加大两个力度、强化两个重点的对策办法. 相似文献
95.
随着沿海地区经济的不断发展,沿海地区渔业和水产品进出口贸易的发展取得了巨大的成就。以我国沿海地区11个省市2003—2007年的水产品进出口贸易额、固定资产投资额、渔业劳动力和渔业经济产值数据为样本,采用出口扩展型生产函数模型,运用面板数据进行实证分析。实证结果表明:沿海地区各省市水产品出口、进口都对渔业经济增长有正向的拉动作用,且拉动作用的趋势相同。 相似文献
96.
Oto J. Okwu 《Journal Of Agricultural & Food Information》2013,14(3-4):315-328
This study characterized farmer users and nonusers of mass media as channels of agricultural information. A structured interview was used to obtain data from 316 randomly selected farmers in Benue State, Nigeria. The data were subjected to discriminant analysis and the following socioeconomic characteristics significantly differed at a 5% level of probability between users and nonusers of mass media (and their F-ratio values): education (6.30), income (5.12), gender (4.84), and socioeconomic status (4.83). Farmer users of mass media are therefore those who have good level of education, belong to a relatively high income bracket, and are typically male and of a relatively high socioeconomic status. Farmers’ socioeconomic characteristics should be considered in planning mass media usage in agricultural information dissemination. 相似文献
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随着市场经济发展需要,农技推广工作,只有适应新形势、创新新方法,才能推动农业科技的快速发展。分析了当前农业科技推广中的现状与存在问题,并提出几点建议,谨供参考。 相似文献
100.
Hüttner K Leidl K Pfeiffer DU Jere FB Kasambara D 《Tropical animal health and production》2001,33(3):201-218
The social background, farm characteristics, indicators of income and self-evaluation returns of 96 randomly selected users of a Basic Animal Health Service (BAHS) programme in northern Malawi were compared with those of 96 matched past-users and 96 non-users, respectively. All 288 farms were visited between July and October 1997. Data analysis was performed using univariate and multivariate techniques. The results showed that, on average, BAHS users had larger cattle herds (16.3) than part-users (14.7) or non-users (12.4). Similarly, the annual yields of crops were higher for users compared to either of the other groups. Users occupied better houses and owned a larger number of farm and household items than did part-users or non-users. A third of all farmers were engaged in additional income generation to lessen the risk of poverty. However, analysis of the livestock management and the educational background of the farmers suggested that usage of the BAHS programme was not only determined by already existing `wealth'. Improved livestock husbandry and management measures, which do not require capital investment, were more frequently applied by users compared to either of the other groups. Non-users and part-users had attained a lower level of education, were less open towards improved farming methods and felt less knowledgeable than BAHS users. The average straight-line distances from farms using BAHS to their respective village animal health worker (2.2 km) or veterinary assistant (2.9 km) were similar but varied according to ecological zone. Intensified extension and awareness meetings in villages will be required to get more non-users involved in BAHS. 相似文献