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Conflicts due to damage caused by wildlife pose serious threats to conservation. In addition, wildlife damage incurs severe economic loss to communities living in the close vicinity of the park, affecting the livelihoods and well-being of locals. While different studies have emphasised identification and quantification of crop damage problems, studies highlighting the means used for crop protection and their effectiveness are limited. This study aimed to examine the effectiveness of means used by communities to protect their crops against wildlife. 117 households were visited at two Buffer Zone villages of Bardia National Park, Nepal. Findings suggested that crop depredation by wildlife was a function of several factors, such as the distance of the farmland from the park, the size of the crop raiding animals and the frequency of attacks on the farmland, and the type of crops. Ten different means were identified by communities which were used regularly to prevent crop damage. Households combined both traditional and modern means to guard their crop against the wild animals. Means differed according to the animals as well as crops being protected. Among all these means, Machan (i.e. watch towers) combined with other means such as throwing flaming sticks and group shouting were the most effective and safest modes of crop guarding for all kinds of animals and crops. Trench and Bio-fencing were effective mostly for deer species. However, crop guarding was an intensive process and no means were able to completely prevent crop damage. Problem animals differed according to the villages and crops being damaged, which suggests that employment of single means would be ineffective. Site-specific management strategies and economic as well as technical support from funding organisations would be most useful to minimise crop loss. In addition information exchange and learning between farmers and the park management about different mitigating means could support and prepare farmers for improvement in the means.  相似文献   
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Clavibacter michiganensis subsp. michiganensis (Cmm) is a quarantine organism in Europe and in many other countries. It is one of the most severe bacterial pathogens affecting tomato. Screening tomato plants for their resistance level to Cmm requires a large amount of space under quarantine conditions and is therefore costly. This project developed a new inoculation protocol on in vitro tomato plants to facilitate a more economic and higher throughput disease screening. A new method using the PathoScreen system was tested to localize green fluorescent protein-tagged Cmm in planta and to quantify the pathogen based on the percentage of corrected GFP (cGFP%). The system was sensitive in detecting the GFP-tagged Cmm in the shoots, but in the roots a high autofluorescence masked detection and thus sensitivity of the assay. The in vitro protocol was tested on several wild relatives of tomato, which were previously screened in a greenhouse assay. The correlation between wilt symptoms in vitro and wilt symptoms in the greenhouse was overall moderate (= 0.6462). The protocol worked well in differentiating the two parents that were used in the mapping studies. This study shows that the in vitro protocol can be efficiently used for resistance breeding in many tomato genotypes.  相似文献   
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The decrease in stratospheric ozone has heightened concern over the consequences of increasing solar UV-B radiation on plants. The present study was conducted to evaluate the interactive effects of supplemental UV-B (sUV-B: 280–320 nm) and mineral nutrients on a leafy vegetable amaranthus (Amaranthus tricolor L. var Pusa badi) under natural field conditions in a dry tropical environment. The nutrient treatments were recommended dose of NPK, 1.5 times recommended dose of NPK, 1.5 times recommended dose of N and 1.5 times recommended dose of K sUV-B radiation inhibited growth and biomass accumulation and altered the patterns of biomass partitioning. In K amended plants larger proportion of biomass has been translocated to roots which further increased under sUV-B treatment. The application of 1.5 times recommended dose of NPK reduced the magnitude of yield loss. The study shows that amaranthus is a potentially UV-B sensitive species and a higher NPK dose above the recommended is required to minimize the adverse impact of sUV-B.  相似文献   
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A wide range of land management practices, including application of fertilizers, contour‐plowing, stone bunds, mulching and agroforestry, have been adopted by farmers in the Jos Plateau to control degradation. This study examined the relative popularity of 13 land management practices based on mainly qualitative primary information collected through a questionnaire survey of 150 farm households and group discussions held during May to August 2007. The results of the analysis revealed four practices, namely, application of chemical fertilizers and farm yard manure, intercropping and crop rotation were highly popular. These practices generally need little technical skills, show positive short‐term benefits and short establishment time, suggesting that the benefits of increased productivity can be obtained quite quickly. Practices like agroforestry, mulching, legume cultivation and crop residue barriers were moderately popular as they take time, sometimes up to 3 years, before some benefits could be manifested. For farmers dependent on the farm income without any financial back‐up, this is too long as many do not have the economic capital to apply a practice that will only start showing benefits after a few years. The least popular practices were stone and earthen bunds, grass strips, alley cropping and contour‐plowing. These prove to be more labour intensive, and with dwindling labour force in the area, the adoption trend favours other practices requiring relative less labour. Farmers could not control land degradation effectively, despite their efforts made to manage land. Broad policy recommendations are made in line with findings of the analysis. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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OBJECTIVE: Breast-feeding (BF) provides the ideal food for the healthy growth and development of infants. The prevalence of BF in Lebanon shows mixed results. The present study was the first large-scale, extensive survey on BF parameters in Lebanon that aimed to explore demographic, socio-economic and other fundamental issues associated with the initiation and duration of BF by Lebanese mothers.DESIGN: The survey was cross-sectional in design and administered over 10 months.SETTING: Information on all variables was collected from mothers at health centres.SUBJECTS: Two-stage sampling was conducted to select participants. A total of 1,000 participants were randomly selected. A consent form was provided to each participant. Data were collected from 830 of these.RESULTS: Almost all mothers were Lebanese, married and had given birth in a hospital. About a third stated that breast milk was the first food introduced after birth. Although 55.9% started breast-feeding their newborns within a few hours after birth, and 18.3% within half an hour, 21.2% replied that they initiated BF a few days after birth. Only 4.6% of the mothers replied that they never breast-fed their infant. Timing of initiation of BF was associated with the type of delivery (vaginal/Caesarean section) and hospital-related factors (rooming-in, night feedings and frequency of mother-infant interaction). Of the mothers who breast-fed exclusively beyond 6 months, 86.7% had initiated BF a few hours following delivery, while only 13.3% had initiated BF a few days later. Compared with the exceptionally high proportion of BF initiation, exclusivity of BF was low, dropping to 52.4% at 1 month. Exclusivity of BF was also associated with place of residence (urban/rural) and negatively associated with educational level of the mother. Duration of BF was inversely associated with the use of pain killers during delivery and maternal education. Rural mothers and those who practised exclusive BF maintained BF for a longer duration.CONCLUSION: Initiation rates of BF are very high in Lebanon but rates of exclusive BF are low and duration of BF is short. Future research targeting the factors associated with BF, with particular emphasis on exclusivity, is needed. For the 95.4% of mothers who initiated BF, an ecological perspective on intervention aimed at women and their social support system is required to improve duration and exclusivity.  相似文献   
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Spatial heterogeneity is an inherent feature of soils that has significant functional implications, particularly when the activities of soil microbial communities are considered. The main goal of this study was to determine the physical–chemical properties best correlated with changes in microbial community composition in an agricultural ecosystem, as part of an effort to better understand what environmental factors control the distribution and organization of soil microbes. In addition, we sought to determine: (i) whether these factors vary depending on the spatial extent considered, and (ii) whether different subsets of the microbial community were linked with different environmental variables. This analysis was conducted in a spatially explicit manner via a series of Mantel and partial Mantel tests to examine the relationship between the microbial community and the soil microenvironment while controlling for any shared spatial structure. Two-hundred soil samples were collected with separation distances ranging from 2.5 cm to 11 m, and the multi-scale spatial distributions of soil carbon (C), nitrogen (N), organic matter (OM), texture, and bacterial abundance were compared with previously published analyses of microbial community structure. The results of the spatial analysis of soil properties were similar to those obtained for the microbial communities, and considerable spatial structure was detected, even at very small scales (i.e., ≤40 cm). A strong link between the microbial community and the soil physical–chemical properties was established, and different subsets of the microbial community responded differently to the various environmental properties. C and N affected the widest portion of the microbial community, while patterns in OM distribution and soil texture were selectively correlated with specific groups of microbes. Collectively, these results demonstrate the value of considering multiple spatial scales when studying community–environment interactions, and that one's interpretation of these relationships is critically dependent on the scale of the investigation and the aspect of the community considered. Understanding how microbial communities develop and organize will help scientists interpret the interplay of dispersal, disturbance, and local dynamics in spatial mosaics, and may have important implications for land management following natural disturbances or human alterations.  相似文献   
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ObjectivesThe purposes of this study were to evaluate if (1) Angiostrongylus vasorum-infected dogs recruit pulmonary arteriovenous (AV) shunts attenuating the development of pulmonary hypertension (PH), detectable using saline contrast echocardiography, (2) anthelmintic therapy causes an acute increase in pulmonary arterial pressure (PAP), (3) Tissue Doppler Imaging (TDI) allows detection of mild changes in right ventricular function secondary to pulmonary (vascular) disease.Animals6 healthy Beagle dogs, each infected with 200 A. vasorum larvae.MethodsConventional, TDI and contrast echocardiography, invasive PAP measurements before (T0), 7–12 weeks post infection (wpi, T1), and 1–5 days post therapy (dpt, T2).ResultsAll dogs had patent infections 7–8 wpi and respiratory signs 6–9 wpi. PAP was mildly but significantly increased at T2. Saline contrast echo was positive in 3/6 dogs at T1 and 4/6 dogs at T2. Pulmonary transit time did not change. Of all numeric echocardiographic parameters, only a non-significant decrease in the E′ wave and inversion of E′/A′ ratio in 3 dogs at T2 could be observed. Two of these had mild PH and negative saline contrast echocardiography.ConclusionA. vasorum infection causes only a mild increase in PAP following inoculation and anthelmintic therapy. The absence of important PH may in part be explained by the recruitment of AV shunts in the presence of vascular obstructive disease. TDI echocardiographic parameters may be more sensitive to detect mild changes in RV function than conventional parameters.  相似文献   
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