RESUMO
A growing concern on the deleterious effects of chemical inputs to the environment has been on the rise from the excessive use of chemical inputs leading to soil and water pollution, destruction to fauna and microbial communities, reduced soil fertility and increased crop disease susceptibility. In the Great Mekong Region (GMR), a large majority of the population relies on agriculture and faces severe challenges including decline in soil fertility, increased pests and diseases, leading to lower ecosystem productivity. In this region, over-dependence on chemical fertilizers also continues to impact negatively on soil health and the wider ecosystem. Agroecological practices, and beneficial microorganisms in particular, offer an affordable and sustainable alternative to mineral inputs for improved plant nutrition and soil health for optimal crop performance and sustainable production. Biofertilizers are a key component in integrated nutrient management as well as for increased economic benefits from reduced expenditure on chemical fertilizers, holistically leading to sustainable agriculture. To cope with the need for biofertilizer adoption for sustainable agricultural production, the countries in the GMR are putting efforts in promoting development and use of biofertilizers and making them available to farmers at affordable costs. Despite these efforts, farmers continue to use chemical fertilizers at high rates with the hope of increased yields instead of taking advantage of microbial products capable of providing plant nutrients while restoring or improving soil health. This study explored the current agricultural practices in the six countries in the GMR (China, Vietnam, Myanmar, Thailand, Cambodia and Lao PDR), the critical need for sustainable agroecological practices with a special emphasis on biofertilizers. We highlighted the current status, distribution, adoption and gaps of biofertilizer production in the GMR, in order to obtain an insight on the nature of biofertilizers, efficacy and production standards, adoption or lack of biofertilizers in the GMR.
Assuntos
Agricultura , Fertilizantes , Camboja , China , Tailândia , VietnãRESUMO
10.3969/j.issn.2095-4344.2013.26.016
RESUMO
BACKGROUND:The bony crista has been found in the distal humeral medullary cavity,but its specific morphological characteristics and clinical significance are not clear.OBJECTIVE:To study the morphology of bony crista inside the distal intramedullary of the human humerus and its potential clinical relevance.DESIGN,TIME AND SETTING:CT scanning and measurement as well as visualized observation to the specimen for the dry adult humeri was performed at CT Room and Department of Orthopaedics,First Affiliated Hospital,Nanchang University from June to December 2007.MATERIALS:A total of 80 dry adult humeri (left:49;right:31) were purchased from the Department of Anatomy,Medical College of Nanchang University,excluding the fractured and lesion humerus.METHODS:The low 1/3 of eighty human humeri were scanned by 16 layer spiral CT.The morphological features of the intramedullary bony prominence above the olecranon fossa was described in terms of coronal plane,sagittal plane and transverse section after three-dimensional reconstruction.The low 1/3 of twenty humeri were then split vertically in the middle line in coronal plane,to view the intramedullary bony crista directly.MAIN OUTCOME MEASURES:The bony crista mainly located on the medial or lateral side,the range of the bas'dar part of the bony crista,alinement characteristic of the bony crista.RESULTS:The extent of intramedullary bony crista ranged from 1.9 to 3.2 cm (mean 2.6 cm) above the olecranon fossa,the density similar to cortical bone,with an basement posterior,and medial part and lateral side intero-inferiody incline.59 out of the 80 humeri,medial side dorminated;on the rest humeri the lateral side dorminated.2 or 3 parallel lines on the dorminate side,irregular alignment on the other side.CONCLUSION:The study described the morphology of the distal intramedullary bony crista of the humerus,which has never been reported so far.In addition,its clinical relevance in terms of the internal fixation of fracture on the distal humerus and elbow arthroplasty was also demonstrated.
