First adaptation of quinoa in the Bhutanese mountain agriculture systems

Bhutan represents typical mountain agriculture farming systems with unique challenges. The agriculture production systems under environmental constraints are typical of small-scale agricultural subsistence systems related to family farming in the Himalayan Mountains with very low level of mechanization, numerous abiotic stresses influenced by climate and other socio-economic constraints. Quinoa was first introduced in 2015 through FAO's support to Bhutan as a new crop to enhance the food and nutritional security of the Bhutanese people. The main objective was to adapt this versatile crop to the local mountain agriculture conditions as a climate resilient crop for diversifying the farmer's traditional potato and maize based cropping systems. Ten quinoa varieties were evaluated at two different sites representing contrasted mountain agroecologies in Bhutan and were tested during the two agricultural campaigns 2016 and 2017. Yusipang (2600 masl) represents the cool temperate agroecological zone, and Lingmethang (640 masl) the dry subtropical agroecological zone. The sowing time differed depending on the growing season and elevation of the sites. Results indicate that quinoa can be successfully grown in Bhutan for the two different agroecological zones. The grain yields varied from 0.61 to 2.68 t.ha-1 in the high altitude areas where quinoa was seeded in spring and harvested in autumn season. The grain yield in the lower elevation ranged from 1.59 to 2.98 t.ha-1 where the crop was sown in autumn and harvested in winter season. Depending on genotypes' characteristics and agroecological zones, crop maturity significantly varied from 92 to 197 days with all genotypes maturing much earlier in the lower elevations where mean minimum and maximum temperatures during the growing season were higher. Quinoa is rapidly promoted across different agroecological contexts in the country as a new climate resilient and nutrient dense pseudo cereal to diversify the traditional existing cropping system with some necessary adjustments in sowing time, suitable varieties and crop management practices. To fast track the rapid promotion of this new crop in Bhutan, four varieties have been released in 2018. In just over three years, the cultivation of quinoa as a new cereal has been demonstrated and partially adapted to the maize and potato based traditional cropping systems under the Himalayan mountain agriculture. Quinoa is also being adapted to the rice based cropping system and rapidly promoted as an alternative food security crop in the current 12th Five Year national development plan of Bhutan. To rapidly promote quinoa cultivation, the Royal Government of Bhutan is supporting the supply of free quinoa seeds, cultivation technologies and milling machines to the rural communities. To promote the consumption and utilization of quinoa at national level, consumer awareness are created by preparing and serving local Bhutanese dishes from quinoa during local food fairs and farmer's field days. In addition, the Royal Government of Bhutan has included quinoa in the school feeding programme recognizing the high nutrient value of the crop for enhancing and securing the nutritional needs of the young children

Prediction of performance of the DVB-SH system relying on mutual information

DVB-SH (Digital Video Broadcasting-Satellite Handled) is a broadcasting standard dedicated to hybrid broadcasting systems combining a satellite and a terrestrial part. On the satellite part, dedicated interleaving and time slicing mechanisms are proposed to mitigate the effects of Land Mobile Satellite (LMS) channel, based on a convolutional interleaver. Depending on the parameters of this interleaver, this mechanism enables to split in time a codeword on duration from 100 ms to about 30s. This mechanism signi?cantly improves the error recovery performance of the code but in literature, exact evaluation at system level of this improvement is missing. The objective of this paper is to propose a prediction method compatible with fast simulations, to quantitatively evaluate the system performance in terms of Packet Error Rate (PER). The main dif?culty is to evaluate the decoding probability of a codeword submitted to several levels of attenuation. The method we propose consists in using as metric the Mutual Information (MI) between coded bit at the emitter side and the received symbol. It is shown that, by averaging the MI over the codeword and by using the decoding performance function g such that PER=g(MI)determined on the Gaussian channel, we can signi?cantly improve the precision of the prediction compared to the two other methods based on SNR and Bit Error Rate (BER). We evaluated these methods on three arti?cial channels where each codeword is transmitted with three or four different levels of attenuations. The prediction error of the SNR-based (resp. the input BER-based) method varies from 0.5 to 1.7 dB (resp. from 0.7 to 1.2 dB) instead of the MI-based method achieves a precision in the order of 0.1 dB in the three cases. We then evaluate this method on real LMS channels with various DVB-SH interleavers and show that the instantaneous PER can also be predicted with high accuracy