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101.
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
102.
国外土地整理实践对我国土地整理的启示 总被引:1,自引:0,他引:1
土地整理在我国起步较晚,很多理论还不成熟。采用文献参阅法,从土地整理的发展阶段、内容和特点等方面介绍了德国、俄国和荷兰等国外土地整理的基本情况,并由此得出其对我国土地整理的启示:建立健全土地整理法律政策,重视土地整理的权属调整,拓宽土地整理融资渠道,重视土地整理中的生态环境保护,积极推动土地整理公众参与和高度重视土地整理规划等。 相似文献
103.
The effects of field aging (0–28 days) and pheromone loading rate on the longevity of red rubber septa loaded with the sex
pheromone blend of the oriental fruit mothGrapholita molesta (Busck), were evaluated in North Carolina apple orchards in 2002. Separate field tests examined the influence of trap height
and pheromone loading rate of rubber septa on trap catches of adultG. molesta males in an abandoned orchard. The loss of the major pheromone component, (Z)-8-dodecenyl acetate (Z8–12:OAc), from red rubber
septa over a 4-week period exhibited a relatively constant release rate with 30, 100 and 300 μg pheromone. Trap catch was
significantly higher in pheromone traps placed in the upper canopy than in those in the lower canopy. Pheromone traps baited
with 100μg lures caught more moths compared with those loaded with 300 μg. There was no apparent relationship between pheromone
trap catch and septa age, with trap catch appearing to be primarily a function ofG. molesta population density.
http://www.phytoparasitica.org posting May 14, 2006. 相似文献
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研究土地综合整治对农户生计韧性的影响,对科学研判土地综合整治的实践效应、实现农户生计的可持续发展具有重要意义。本文基于湖北省部分县市的农户调研数据,运用双重差分模型探讨土地综合整治对农户生计韧性的影响效应。基准回归结果表明,土地综合整治可促使农户生计脆弱性显著降低,并显著提高其生计恢复力和生计韧性,且多种检验均显示研究结果稳健。异质性分析发现,土地综合整治对不同类型农户生计韧性的提升作用呈现“低收入—低依赖”>“高收入—低依赖”>“低收入—高依赖”>“高收入—高依赖”的分异特征,还受到地貌类型差异的影响,平原地区土地综合整治对农户生计韧性的提升效果大于丘陵地区。因此,土地综合整治应遵循“以人为本、夯实民生”的发展理念,树立统筹协调的系统治理观,全面优化农地功能与效能,构建低环境风险、良性运转的土地可持续利用格局,坚持“输血”与“造血”并举,因地制宜挖潜区域产业特色,才能有效降低农户生计脆弱性、增强其内生发展动力,实现农户生计的韧性发展。 相似文献
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将SiO2与天然橡胶的制备工艺相结合,先以价格低廉的水玻璃为原料,采用溶胶-凝胶法制备SiO2溶胶和凝胶,再以天然鲜胶乳共沉-共凝制备SiO2/NR复合材料,考察了制备工艺条件对复合材料力学性能的影响。结果表明,制备SiO2/NR复合材料较适宜的复合工艺为院水玻璃与乙酸乙酯反应温度30益,乙酸乙酯和水玻璃溶液中所含SiO2的摩尔比n为0.8∶1,水玻璃浓度为6.5%。当SiO2用量为10份时,复合材料的拉伸强度和撕裂强度分别达到了33.4MPa和47.1kN·m-1。 相似文献
110.
Weed control in conservation agriculture systems of Zimbabwe: Identifying economical best strategies
Weed management under conservation agriculture (CA), especially when manually controlled is one of the major setbacks for the widespread adoption of CA in southern Africa. This study was conducted at three on-station and three on-farm sites: CIMMYT-Harare, Domboshawa Training Centre and Henderson Research Station (on-station sites), Hereford farm, Madziva communal area and Shamva communal area (on-farm sites). The evaluation focused on the effect of initial herbicide application and succeeding manual weeding whenever weeds were 10 cm tall or 10 cm in length for grasses with stoloniferous–rhizomatous growth habit. Weeds counts, weeding time and grain yields were collected at all on-station sites. At the on-farm sites, weed counts were done before weeding and a number of farmers were timed during weeding. The results showed that herbicides use reduced the weed density and time taken on weeding at all sites. Combining herbicides e.g. atrazine, glyphosate and metalachlor had the lowest weed density and weeding time at all sites. However, the treatments had no effect on maize grain yields suggesting that appropriate and timely manual weeding reduced crop/weed competition. Herbicides treatments had higher input costs than manual weeding due to the additional cost of herbicide but the treatment with manual weeding only had more overall labour days compared to the mixture of three herbicides. In order to achieve economic benefits, smallholder farmers may use the time for value addition e.g. expand cropped land area, use time for value addition, or sell new products on the market. Herbicides use reduces the manual labour needed to control weeds and minimise total crop failure due to untimely weeding hence, herbicides are an important but not the only weed control option under CA systems in Zimbabwe. 相似文献