53 research outputs found

    Characterizing and mapping cropping patterns in a complex agro-ecosystem: An iterative participatory mapping procedure using machine learning algorithms and MODIS vegetation indices

    Get PDF
    Accurate and up-to-date spatial agricultural information is essential for applications including agro-environmental assessment, crop management, and appropriate targeting of agricultural technologies. There is growing research interest in spatial analysis of agricultural ecosystems applying satellite remote sensing technologies. However, usability of information generated from many of remotely sensed data is often constrained by accuracy problems. This is of particular concern in mapping complex agro-ecosystems in countries where small farm holdings are dominated by diverse crop types. This study is a contribution to the ongoing efforts towards overcoming accuracy challenges faced in remote sensing of agricultural ecosystems. We applied time-series analysis of vegetation indices (Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI)) derived from the Moderate Resolution Imaging Spectrometer (MODIS) sensor to detect seasonal patterns of irrigated and rainfed cropping patterns in five townships in the Central Dry Zone of Myanmar, which is an important agricultural region of the country has been poorly mapped with respect to cropping practices. To improve mapping accuracy and map legend completeness, we implemented a combination of (i) an iterative participatory approach to field data collection and classification, (ii) the identification of appropriate size and types of predictor variables (VIs), and (iii) evaluation of the suitability of three Machine Learning algorithms: Support Vector Machine (SVM), Random Forest (RF), and C5.0 algorithms under varying training sample sizes. Through these procedures, we were able to progressively improve accuracy and achieve maximum overall accuracy of 95% When a small sized training dataset was used, accuracy achieved by RF was significantly higher compared to SVM and C5.0 (P < 0.01), but as sample size increased, accuracy differences among the three machine learning algorithms diminished. Accuracy achieved by use of NDVI was consistently better than that of EVI (P < 0.01). The maximum overall accuracy was achieved using RF and 8-days NDVI composites for three years of remote sensing data. In conclusion, our findings highlight the important role of participatory classification, especially in areas where cropping systems are highly diverse and differ over space and time. We also show that the choice of classifiers and size of predictor variables are essential and complementary to the participatory mapping approach in achieving desired accuracy of cropping pattern mapping in areas where other sources of spatial information are scarce

    Landscape-based nutrient application in wheat and teff mixed farming systems of Ethiopia: farmer and extension agent demand driven approach

    Get PDF
    Introduction: Adapting fertilizer use is crucial if smallholder agroecosystems are to attain the sustainable development goals of zero hunger and agroecosystem resilience. Poor soil health and nutrient variability characterize the smallholder farming systems. However, the current research at the field scale does not account for nutrient variability across landscape positions, posing significant challenges for targeted nutrient management interventions. The purpose of this research was to create a demand-driven and co-development approach for diagnosing farmer nutrient management practices and determining landscape-specific (hillslope, mid-slope, and foot slope) fertilizer applications for teff and wheat. Method: A landscape segmentation approach was aimed to address gaps in farm-scale nutrient management research as well as the limitations of blanket recommendations to meet local nutrient requirements. This approach incorporates the concept of interconnected socio-technical systems as well as the concepts and procedures of co-development. A smart mobile app was used by extension agents to generate crop-specific decision rules at the landscape scale and forward the specific fertilizer applications to target farmers through SMS messages or print formats. Results and discussion: The findings reveal that farmers apply more fertilizer to hillslopes and less to mid- and foot slopes. However, landscape-specific fertilizer application guided by crop-specific decision rules via mobile applications resulted in much higher yield improvements, 23% and 56% at foot slopes and 21% and 6.5% at mid slopes for wheat and teff, respectively. The optimized net benefit per hectare increase over the current extension recommendation was 176and176 and 333 at foot slopes and 159and159 and 64 at mid slopes for wheat and teff (average of 90and90 and 107 for wheat and teff), respectively. The results of the net benefit-to-cost ratio (BCR) demonstrated that applying landscape-targeted fertilizer resulted in an optimum return on investment (10.0netprofitper10.0 net profit per 1.0 investment) while also enhancing nutrient use efficiency across the three landscape positions. Farmers are now cognizant of the need to reduce fertilizer rates on hillslopes while increasing them on parcels at mid- and foot-slope landscapes, which have higher responses and profits. As a result, applying digital advisory to optimize landscape-targeted fertilizer management gives agronomic, economic, and environmental benefits. The outcomes results of the innovation also contribute to overcoming site-specific yield gaps and low nutrient use efficiency, they have the potential to be scaled if complementing innovations and scaling factors are integrated

    ARARI report on N2Africa bridging year progress in Ethiopia (2013)

    No full text

    Symbiotic Blue Green Algae (Azolla): A Potential Bio fertilizer for Paddy Rice Production in Fogera Plain, Northwestern Ethiopia

    Get PDF
    A field experiment was carried out in Fogera plain, where lowland rice is widely grown, to assess the adaptability and yield of Azzola strains and to determine the level of nitrogen they generate in 2005 and 2006. A year earlier, 2004, the two Azolla strains (Azolla filiculoides and Azolla microphylla) were introduced from India. They were maintained and multiplied in plastic containers at Adet in a greenhouse and then inoculated into concrete tanks for testing their adaptability. Both strains were well adapted to Adet condition. The actual experiment was laid out in a randomized complete block design replicated three times. In the summer season, Azolla filiculoides gave an average of 48 tons/ha (range: 42-56.4 tons) and Azolla microphylla yielded 40 tons/ha fresh biomass (range: 30-45 tons). In autumn and winter seasons, biomass production was reduced because of fluctuating temperatures. An average of 54.4 t ha-1 of Azolla fresh biomass was harvested at Fogera. Maximum plant height, number of tillers, straw yield and grain yield of rice was recorded on the treatment that was planted by using 64 kg N + 20 kg P ha-1 followed by Azolla filiculoides + 20 kg P ha-1, 32 kg N + 10 kg P ha-1. Inoculation of Azzola by incorporating once into the soil has increased rice yield by 911 kg ha-1 (19%) on Azolla filiculoides plots and 721 kg ha-1 (15%) on Azolla microphylla plots. However, there was temperature fluctuation and colonization of Azolla roots by algae. Multiplication and maintenance of Azolla needs special attention. It also needs continuous watering to a depth of 5 -10 cm and P fertilizer application, thus, irrigation facility and alternate P sources are vital. Azolla gives a lot of biomass and it is easy to manage and establish, which means that it is logical and cost-effective to use it as biofertilizer for paddy rice. Its effect on high value and perennial crops may be the subject of further research.Keywords: Azolla, biofertilizer, fresh biomass, nitrogen, rice, symbioti
    corecore