Contribution of GIS to Soil Landscape Mapping by Multi-Criteria Analysis Using Weighting: The Case of the Square Degrees of M’Bahiakro (Centre) and Daloa (Centre-West) in Ivory Coast

As part of the drive to improve coffee and cocoa production in Ivory Coast, studies are carried out to identify soils that are favourable for these crops. It is therefore necessary to orientate soil investigations based on reliable criteria that best discriminate soil cover. With this in mind, this study is being carried out to help improve survey methods by mapping soil landscapes. It uses GIS and weighted multicriteria analysis. To do this, satellite images were processed and the geological map of the square degrees of M’Bahiakro and Daloa was reclassified. The results show that relief is the main factor in soil landscape differentiation, with respective weights of 0.58 and 0.67 for the forest and pre-forest zones. In contrast, the weight of geological formation in soil landscape differentiation remains low (0.05 for the forest zone and 0.07 for the pre-forest zone). The criteria used on the base of aggregation sum methods have made it possible to formulate soil landscape mapping prediction functions according to agro-ecological environments in the humid intertropical zone. This is essential for the orientation of soil survey work. Nevertheless, other comparative methods, such as the coding mapping method, could provide elements for discussion to validate the models.

Multicriteria Analysis by Codification for the Determination of Soil Landscape Units in Forest and Pre-Forest Zones of Cote D’Ivoire: The Case of the Square Degrees of M’Bahiakro and Daloa

The present study, carried out in the forest (Daloa) and pre-forest (M’Bahiakro) zones of Cote d’Ivoire, aims to determine soil landscape units using the coding method. Geological maps and satellite images (SRTM and Landsat) were used for this purpose. The methodological approach adopted consisted in producing maps of slope, geology, land use and topography using the codification method. These various maps, integrated into a GIS using the coding aggregation method, were used to generate soil landscape maps. Twenty-seven (27) soil landscapes have been identified for the pre-forest zone (M’Bahiakro), with a strong dominance of acid rock over a moderate relief under savannah, forest/degraded forest and crops/fallow. However, the forest zone (Daloa), with forty-one (41) soil landscapes identified over the entire zone, is characterized by a majority of mafic rocks on a medium altitude under forest/degraded forest, water and crops/fallow. The criteria used from the codification method (sum of aggregations) made it possible to predict the spatial distribution of soil map units according to agro-ecological environments in the humid intertropical zone. This is essential for the orientation and reinforcement of soil survey tools. However, a comparative evaluation of the different multicriteria analysis methods for coding and weighting soil landscape unit mapping would enable us to identify the most suitable and efficient method for drawing up base maps for soil surveys.

Effects of Calcium and Magnesium on Phosphorus Availability in Ferralsols and Rice Production in Forest Zones of Côte d’Ivoire

Phosphorus bioavailability has long been a recurring problem in tropical acid soils. A pot experiment was carried out during three (3) successive rice production cycles at Adiopodoumé to evaluate the response of the NERICA 5 rice accession to various doses of calcium, magnesium and phosphorous. The experiment was conducted using a randomized split-plot design. The interactive effects of calcium carbonate (0, 25, 50 and 75 kg·Ca·ha-1) and magnesium sulfate (0, 25, 50 and 75 kg·Mg·ha-1) and Togo natural phosphate (0, 25, 50 and 75 kg·P·ha-1) were determined at each production cycle. The results showed that single-dose natural phosphate supplementation for three cropping cycles resulted in an average enrichment of around 2 mg·P·kg-1 after each trial following its continuous dissolution, with an increase in DSP (33.31% to 70.52%). The study revealed one strategy for managing and enhancing native P with cations and another for exogenous P: there would be a synergy of Ca/Mg on native P, whereas an antagonism would characterize the two parameters in phosphate fertilization.

A field guide for aging passerine nestlings using growth data and predictive modeling

Background:Accurate nestling age is valuable for studies on nesting strategies,productivity,and impacts on repro-ductive success.Most aging guides consist of descriptions and photographs that are time consuming to read and subjective to interpret.The Western Bluebird(Sialia mexicana)is a secondary cavity-nesting passerine that nests in coniferous and open deciduous forests.Nest box programs for cavity-nesting species have provided suitable nesting locations and opportunities for data collection on nestling growth and development.Methods:We developed models for predicting the age of Western Bluebird nestlings from morphometric meas-urements using model training and validation.These were developed for mass,tarsus,and two different culmen measurements.Results:Our models were accurate to within less than a day,and each model worked best for a specific age range.The mass and tarsus models can be used to estimate the ages of Western Bluebird nestlings 0-10 days old and were accurate to within 0.5 days for mass and 0.7 days for tarsus.The culmen models can be used to estimate ages of nest-lings 0-15 days old and were also accurate to within less than a day.The daily mean,minimum,and maximum values of each morphometric measurement are provided and can be used in the field for accurate nestling age estimations in real time.Conclusions:The model training and validation procedures used here demonstrate that this method can create aging models that are highly accurate.The methods can be applied to any passerine species provided sufficient nest-ling morphometric data are available.

Fertigation for Environmentally Friendly Fertilizers Application: Constraints and Opportunities for Its Application in Developing Countries

There is an increasing concern about agriculture’s role in polluting the environment which makes farmers feel guilty about using fertilizers. Fertigation is proposed as a panacea to this dilemma, which by this practice reaffirms the principles of 4Rs which are the right source, at the right rate, right time and right place. The aim of this study was to explore constraints and opportunities for its application in developing countries for environmentally friendly fertilizers application. It is a review of literature from government reports, legislature and published material on fertilization and irrigation initiatives of developing countries which include Rwanda, Nepal, Suriname, Zambia, Panama, Tanzania, Sri Lanka and South Sudan in addition to the case presented of China during the “2016 Environmentally Friendly Fertilizer Production, Application and Demonstration from Developing Countries” training course. The study found that in developing countries there is potential to apply fertigation as a way of environmentally friendly fertilizers application as it has been adopted in China. These opportunities include the following: Abundant natural resources like land and water, less polluted environment, conducive agricultural policies, zero duties levied on imported irrigation equipment. However, a number of limitations also are highlighted including: Lack of investment, lack of infrastructure, lack of information, requires expertise on plant nutrition and management of fertigation system, require soil analysis and proper interpretation which is done by experts. This study provides relevant information for fertigation planning and application in respective developing countries.

关于水科技创新组织模式的思考及建议

针对水技术发展全生命周期时间跨度长、参与主体多的特点,国际上一些地区和机构探索出了成功的模式和经验,有效提高了水科技创新的效率。国际成功经验表明,社会重大需求、技术验证与示范的中试平台、技术创业孵化培育体系以及产业驱动的协同创新等关键要素可加速水技术成果的转化应用。国家水专项等重大科技计划围绕上述要素开展了积极的探索和实践,形成了一些可推广复制的水技术成果转化应用模式。但目前水技术成果走向市场、实现商品化的关键中间环节仍然薄弱,市场还未建立或形成针对这一环节专门的技术验证示范平台、充分的资金投入渠道以及配套的技术孵化培育体系。针对上述问题,有必要从国家层面在基地建设、基金设立、技术孵化方面予以加强。