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111.
A longitudinal observational study on calf morbidity and mortality was conducted in smallholder dairy farms in Ada’a Liben district of Oromia, Ethiopia. A total of 185 calves from 112 market oriented smallholder dairy farms were selected randomly and regularly monitored for clinical health problems up to six months of age. Information on potential risk factors was collected by personal observation during the regular visit to farms and from questionnaire survey conducted during the study period. The overall incidences of crude morbidity and crude mortality were 62 % and 22%, respectively. The most frequent disease syndrome was calf diarrhea with the incidence of 39% followed by joint ill 6%. The other disease conditions/syndromes diagnosed include navel ill, pneumonia, septicemic conditions, congenital problems and miscellaneous cases. Age of the calves, age at first colostrum ingestion and cleanness of the calf barns significantly influenced morbidity. Older calves (greater than three months of age) were at lower risk of crude morbidity than younger calves (less than three months of age) (HR = 0.42, P = 0.001). Higher risk of crude morbidity was observed in calves that ingested their first colostrum meal later than 6 hours of age compared to those that ingested colostrum earlier (HR = 2.24, P = 0.001). Similarly, calves housed in unclean barns were at higher risk of morbidity than calves housed in clean barns (HR = 1.75, P = 0.024). Of the 20 potential risk factors investigated, age was the only factor that was found significantly associated with mortality (HR = 0.04, P = 0.001). Calves older than three months of age were at lower risk of mortality than younger calves.  相似文献   
112.
Therapeutic effects of Sodium Iodide (NaI), Potassium Iodide (KI), ground berries of "Endod" (Phytolacca dodecandra) and Penstrip were evaluated on 70 cases of equine hitoplasmosis (EH). Response to each treatment was assessed using clinical examination of the lesions. Statistically significant difference (P = 0.0036) in therapeutic effect was observed among the different remedies. Cases treated either with a combination of NaI and Penstrip (F = 6.34, P = 0.004) or "Endod" and Penstrip (F = 3.64, P = 0.031) demonstrated significant response. The difference in response to treatment between early and advanced cases of EH was statistically significant (t = 2.22, P = 0.0148).  相似文献   
113.
Local communities often have substantial knowledge related to trends in soil quality and the associated limiting factors. Despite this, soil quality (SQ) degradation is a critical problem in Ethiopia and there is little or insufficient scientific information documenting local community experience in assessing SQ. This paper presents experiences of local communities in diagnosis of SQ and assesses the contribution of local knowledge as a strategy for sustainable development decision making within the Mai-Negus catchment of northern Ethiopia. Participatory transect-walks, group discussions and field observation which complemented by household interview were used to acquire data. Farmers identified SQ indicators e.g., crop yield, soil depth, erosion and sedimentation as their basis of categorizing the soils into high, medium and low SQ. They were also able to identify severely degraded areas (hotspots) and underlying causes. Significant variations (P ≤ 0.05) were shown between the proportions of farmers used certain SQ indicator and those who didn't while categorizing SQ. Local farmers involved in this study demonstrated their capability to suggest appropriate land management solutions for specific problems. This study demonstrates the benefit of involving local farmers in both problem identification and solution development so that anti-degradation technologies can easily be implemented and adopted.  相似文献   
114.
This paper reports on a field study conducted in Kilie catchment, East Shoa Zone, Ethiopia to assess the rate of soil erosion by employing a soil loss prediction model (Universal Soil Loss Equation) integrated with in remote sensing and geographical information systems (RS/GIS), environment and gully measurement techniques. The final soil erosion risk map was produced after multiplication of the six factors involved in the USLE and RS/GIS. Gully measurement showed that the erosion rate is higher for the upland areas than the lowlands due to inappropriate soil and water conservation measures, free grazing by animals and conversion of hillside areas into farmlands. About 97·04 per cent of the study catchment falls within a range of 0–10 t ha−1 yr−1 sheet/rill erosion rate. We found that 2·17 per cent of the study area in the uplands has a soil erosion rate falling between 10 and 20 t ha−1 yr−1. About 0·8 per cent of the study area in the uplands is hit by severe sheet/rill erosion rate within the range of 20–60 t ha−1 yr−1. Gully erosion extent in the study area was evaluated through gully measurement and quantification methods. Gully density of 67 m ha−1 was recorded in the catchment. The gully to plot area ratio was found to be 0·14 on average. Hence, in the upland areas, sustainable land management practices are required in order to reduce the rate of soil erosion. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
115.
Vegetable growers’ knowledge of pest and their control method was assessed in 2014 in East Shewa zone, Ethiopia. Vegetable growers were well aware of key pests of vegetables, although some of them did not consider pests as constraint to vegetable production. All respondents scouted their vegetables for pests and used presence or absence of pest as criterion for spraying. About 76% of the respondents read pesticide label before buying pesticides, while the rest 24% of the respondents did not read pesticide labels. All vegetable growers sprayed insecticide, whereas fungicides and herbicides were applied by 90% and 7% of the respondents, respectively. About 72% of the respondents washed their sprayer after each application day and discharged the washings onto the soil. Moreover, the majority (62%) of the respondents threw empty pesticide containers around the field. Also, it was found that 71% of the respondents did not use personal protective equipment (PPE) while spraying pesticides, but a few used one or two types of PPE. More than half of the respondents sprayed pesticides on mature crops and sold the produce within three to five days.  相似文献   
116.
Twenty-four isolates of Fusarium oxysporum f. sp. ciceris were isolated from wilted chickpea plants obtained from different districts and ‘wilt sickplots’ of central Ethiopia to assess variability in pathogenecity of the populations. Each isolate was tested on 10 different chickpea lines and eight improved chickpea varieties. Isolates showed highly significant variation in wilt severity on the differential lines and improved varieties. Based on the reaction types induced on differential lines, isolates were grouped into four corresponding races. Of the 24 isolates, F13, F20 and F22 were the most virulent. Isolates of race 3 were found in all of the districts and ‘wilt sickplots’ studied. Improved chickpea varieties also showed differential reactions to the isolates. All varieties were resistant to isolates of race 3, while varieties Arerti and DZ-10-4 were resistant to all isolates tested, showing the lowest mean wilt severity. Varieties DZ-10-11 and Maryie were susceptible to isolates F13, F20 and F22 and showed the highest mean wilt severity. Identification of races can be useful in breeding chickpea varieties resistant to wilt. The differential reactions of the improved varieties against different races might be important in managing chickpea wilt through gene deployment.  相似文献   
117.
Although the human domestication of forest and tree resources is often considered to result in resource degradation, it may also lead to improved resource potentials. This paper assesses the nature and dynamics of gum and resin focused woodland exploitation and management systems in Ethiopia in the context of degradation and domestication processes. In three sites with commercial gum resin producing woodlands and production history, we studied variation in (i) woodland management and gum resin production systems and (ii) socio‐economic and biophysical factors that condition the management and production systems. On the basis of their organizational features, we formulated nine production models and related them to different phases of domestication and different degrees of ecosystem degradation. The production systems gradually evolved from the extraction of wild trees to production in an adapted forest system. However, domesticated woodlands with an adapted forest structure and composition and increased provisioning services are still little developed despite decades of production history. Many of these woodlands are undergoing serious degradation because of low quality management practices. This is mainly attributable to existing land use practices and the social arrangements for the production of and trade in the gums and resins. The findings illustrate that domestication involves not only a change in ecological and production systems but also the development of social arrangements for production and trade. We conclude that the status of domestication in a social sense determines whether forests and/or specific forest resources are degraded or aggraded in the sense of resource enrichment. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
118.
Deforestation in African dry forests is widespread and its drivers are complex and vary in space and time. In this paper, we assessed impacts of immigration on dry forests and options for improved management in a resettlement district in north‐western Ethiopia. Key informants interviews, focus group discussions and household questionnaire survey were used to collect data. The results indicated that forests of the district are degrading in spatial coverage and quality. The most important drivers were land use change, excessive wood harvest, grazing pressure and forest fire following immigration. The continuous influx of people with different origins, cultures, religions and lengths of residence in the district underscores absence of social bonds for collective action to regulate access. This, coupled with weak formal regulatory system, market forces and policy incentives for farming, resulted in a near open access situation. Our findings confirm the negative relationships between migration and environment not necessarily because of the mere population number added through immigration but because of lack of regulatory frameworks (formal or informal) and poor social capital. Enforcing existing policy of farm size and putting institutional framework on the ground to regulate rate of immigration, extraction of forest products and to encourage tree planting to meet wood demand are suggested measures. We conclude that Government programmes that opt for resettlement as a measure for poverty alleviation must also have mitigating measures to reducing negative impacts on the natural resource base. Thus, the trade‐off between environment and development must be carefully managed. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
119.
In Boswellia papyrifera (Del.) Hochst natural stands, we stud- ied the association of parasitic plants with B. papyrifera trees from which frankincense was tapped and marketed for domestic and export markets. Data on the rate of infection of parasitic plants on B. papyrifera was collected in three transects located at separate locations around Baha kar, northern Ethiopia. Each transect had ten circular sample plots of 400 m2 and separated by 100 m. Species composition, DBH, height, crown di- ameter, number of main, secondary and tertiary branches and number of parasitic plants on individual trees were recorded. Sixteen tree species were recorded in the combined sample plots. The parasitic plant associ- ated with B. papyrifera was identified as Tapinanthus globiferus. This parasite infected 38% of Boswellia trees in sample plots. The infection rate of the parasitic plant varied from 1 to 33 per Boswellia tree. The infection of T. globiferus on B. papyrifera was predominantly limited to tertiary small branchlets arising from secondary branches; parasitic plants were absent on thick main and secondary branches. In all plots, infectionof T. globiferus was exclusively limited to Boswellia trees. The influence of T. globiferus parasitism on growth of Boswellia trees and its influence on yield of incense production needs further investigation. Management of natural stands for frankincense production should include measures to reduce infection by T. globiferus.  相似文献   
120.
Melophagus ovinus (sheep ked) is one of the most common ectoparasites that contributes to enormous economic losses in the productivity of sheep in many countries. The present study was conducted from January 2012 to July 2013 on M. ovinus collected from sheep at three sites in Ethiopia. Of the sheep studied, 65.7% (88/134) were infested with M. ovinus. The prevalence of M. ovinus was 76% (76/100), 47% (8/17) and 23.5% (4/17) at the Kimbibit, Chacha and Shano sites, respectively. An overall number of 229 M. ovinus specimens (138 females, 86 males and five pupae) and 554 M. ovinus specimens (272 females, 282 males) were collected from young and adult sheep, respectively. Bartonella DNA was detected in 89% (694/783) of M. ovinus using a quantitative Bartonella genus-specific PCR assay targeting the 16S/23S rRNA intergenic spacer region. The sequencing of the PCR products of fragments of the gltA and rpoB genes showed 99.6–100% and 100% homology, respectively, with B. melophagi. Statistically significant variation was not noted in the overall prevalence of Bartonella DNA between female and male M. ovinus. All of the sheep infested with M. ovinus 100% (88/88) harbored at least one M. ovinus specimen that contained Bartonella DNA. This study highlights that B. melophagi in M. ovinus from sheep in highlands in Ethiopia possibly has certain zoonotic importance.  相似文献   
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