Using a conceptual Bayesian network to investigate environmental management of vegetable production in the Lake Taihu region of China

AbstractVegetable farms are one of many nitrogen (N) sources adversely affecting Lake Taihu in eastern China. Given the lack of quantitative “cause and effect” relationships and data relating to these systems, we developed a conceptual Bayesian network to investigate and demonstrate causal relationships and the effects of different mitigation strategies on N exports from vegetable farms in the Lake Taihu region. Structurally, the network comprised one primary transport factor, one primary source factor and three post-mobilisation strategies, and three output factors.In general the network suggests that N exports are more sensitive to transport factors (i.e. runoff volumes) than source factors (i.e. fertiliser application rates) although the cumulative effects of excessive fertiliser were not considered. Post-mobilisation mitigations such as wetlands and ecoditches appear to be particularly effective in decreasing N exports however their implementation on a regional scale may be limited by land availability. While optimising N inputs would be prudent, the network suggests that better irrigation practice, including improved irrigation scheduling, using less imported water and optimising rainfall utilisation would be more effective in achieving environmental goals than simply limiting N supply

Toplumsal cinsiyet eşitliği daha iyi işleyen ekonomilere yol açar mı? Bayes nedensellik ağları analizi

This study explores the existence of relationships between gender inequalities –represented by the components of the World Economic Forum (WEF) Global Gender Gap Index– and the major macroeconomic indicators. The relationships within gender inequalities in education, the labour market, health and the political arena, and between gender inequalities and gross macroeconomic aggregates were modelled with the Bayesian Causal Map, an effective tool that is used to analyze cause-effect relations and conditional dependencies between variables. A data set of 128 countries during the period 2007–2011 is used. Findings reveal that some inequalities have high levels of interaction with each other. In addition, eradicating gender inequalities is found to be associated with better economic performance, mainly in the form of higher gross domestic product growth, investment, and competitiveness.Bu çalışmada Dünya Ekonomik Forumu (WEF) Küresel Cinsiyet Farkı İndeksi‘nin bileşenleri kullanılarak cinsiyet eşitsizliği ile temel makro ekonomik göstergeler arasında bir ilişki olup olmadığı incelenmektedir. Eşitsizlik, eğitim, işgücü piyasası, sağlık ve politika alanlarındaki cinsiyet eşitsizliği ile makroekonomik değişkenler arasındaki ilişkiler, değişkenler arası nedensel ilişkileri incelemek için etkin bir yöntem olarak tanımlanabilecek Bayes Nedensel Ağları yardımı ile modellenmiş ve incelenmiştir. Bunun için 2007-2011 dönemini kapsayan zaman aralığında 128 ülkenin verileri kullanılmıştır. Bulgular bazı alanlardaki eşitsizliklerin yüksek düzeyde birbiri ile ilişkisi olduğunu ortaya koymaktadır. Öte yandan, cinsiyet eşitsizliklerinin ortadan kaldırılmasının, özellikle ülkelerin GSMH, yatırımlar ve rekabet düzeyi açısından daha iyi ekonomik sonuçlara yol açacağı saptanmaktadır

Does Gender Equality Lead to Better-Performing Economies? A Bayesian Causal Map Approach

This study explores the existence of relationships between genderinequalities –represented by the components of the World Economic Forum (WEF)Global Gender Gap Index– and the major macroeconomic indicators. Therelationships within gender inequalities in education, the labour market, health andthe political arena, and between gender inequalities and gross macroeconomicaggregates were modelled with the Bayesian Causal Map, an effective tool that is usedto analyze cause-effect relations and conditional dependencies between variables. Adata set of 128 countries during the period 2007–2011 is used. Findings reveal thatsome inequalities have high levels of interaction with each other. In addition,eradicating gender inequalities is found to be associated with better economicperformance, mainly in the form of higher gross domestic product growth, investment,and competitiveness

Fertilizers and nitrate pollution of surface and ground water: an increasingly pervasive global problem

Nitrate pollution of ground and surface water bodies all over the world is generally linked with continually increasing global fertilizer nitrogen (N) use. But after 1990, with more fertilizer N consumption in developing countries especially in East and South Asia than in the industrialized nations in North America and Europe, nitrate pollution of freshwaters is now increasingly becoming a pervasive global problem. In this review it has been attempted to review the research information generated during the last two decades from all over the world on diferent aspects of nitrate pollution of natural water bodies. It is now evident that not more than 50% of the fertilizer N is directly used by the crops to which it is applied. While a small portion may directly leach down and may reach ground and surface water bodies, a large proportion ends up in the soil organic N pool from where N is mineralized and is taken up by plants and/or lost via leaching during several decades. Present trends of nitrate pollution of freshwaters, therefore, refect legacies of current and past applications of fertilizers and manures. Tools such as simulation models and the natural variation in the stable isotopes of N and oxygen are now being extensively used to study the contribution of fertilizers and other sources to nitrate enrichment of freshwaters. Impacts of agricultural stewardship measures are being assessed and nitrate enrichment of water bodies is being managed using modern digital models and frameworks. Improved water and fertilizer management in agroecosystems can reduce the contribution of fertilizers to nitrate pollution of water bodies but a host of factors determine the magnitude. Future research needs are also considered

Oceanography

How inappropriate to call this planet Earth when it is quite clearly Ocean (Arthur C. Clarke). Life has been originated in the oceans, human health and activities depend from the oceans and the world life is modulated by marine and oceanic processes. From the micro-scale, like coastal processes, to macro-scale, the oceans, the seas and the marine life, play the main role to maintain the earth equilibrium, both from a physical and a chemical point of view. Since ancient times, the world's oceans discovery has brought to humanity development and wealth of knowledge, the metaphors of Ulysses and Jason, represent the cultural growth gained through the explorations and discoveries. The modern oceanographic research represents one of the last frontier of the knowledge of our planet, it depends on the oceans exploration and so it is strictly connected to the development of new technologies. Furthermore, other scientific and social disciplines can provide many fundamental inputs to complete the description of the entire ocean ecosystem. Such multidisciplinary approach will lead us to understand the better way to preserve our "Blue Planet": the Earth

Experimental approach for quantifying crop water use and pollutant loading from agricultural plot

Storm water runoff is the main contributor to non-point source (NPS) pollution in agricultural land. This issue is extremely important in tropical region due to its high intensity and frequent storms. The objectives of this study were to determine the crop coefficient of two vegetable crops – bittergourd (Mormordica Charantia) and chilli (Capsicum Annuum), investigate the mechanism of NPS pollutant transport and the influence of hydrologic regime on the pollutant loading. This study was conducted at the Modern Agriculture Centre in Kluang, Johor, from August 2013 to May 2014. A total of 86 rainfall events were recorded but only 52 storms had generated measurable runoff. Samples of runoff, soil water and groundwater were collected after every rainfall event and analysed for nutrient and sediment contents. Twenty-six reference evapotranspiration (ETo) models which were classified into four different groups were employed and their performance was ranked based on eight different statistical test. Penman model provide the best result in estimating ETo while the Schendel model tended to overestimate the observed pan ET. The limited parameters used in the temperature based group causes poor performance in predicting the ETo values. Crop coefficient (Kc) curves for both crops were developed as the ratio of actual ET measured by minilysimeters to the ET values of the best model. The Kc values for the bittergourd were 0.58, 0.88 and 0.69 while for chili were 0.58, 0.95 and 0.73 for the initial, mid and end growth stages, respectively. More runoff event was observed for the bittergourd as its growing period coincided with the North-East Monsoon. The average runoff-rainfall ratio is less than one percent due to the high hydraulic conductivity of the site. The concentrations of nutrients and sediments were very high with maximum Nitrite (NO2), Nitrate (NO3), Ammoniacal-Nitrogen (NH3-N), Phosphate (PO4), Total Nitrogen (TN), Total Phosphorus (TP), Chemical Oxygen Demand (COD) and Total Suspended Solids (TSS) concentrations in the runoff were 0.385, 10, 4.2, 13.7, 27, 18, 190 and 15000 mg/l respectively. However, the calculated pollutant loading were low due to the remarkably small surface runoff volume. Soil water analysis at 15 and 60 cm soil depth shows a high Phosphorus (P) element leaching to the deeper depth even though P is less mobile. Nitrate concentration showed an increasing trend compared to other nutrients with a maximum of 1.7 mg/l at the end of the study period. The calibration and validation of the Root Zone Water Quality Model (RZWQM2) were carried out to model the leaching of NO3 to the groundwater. The results of this study can be applied to formulate more reliable water management schemes based on the water requirement of the vegetable crops and providing new information for controlling NPS pollution loading from agricultural activities

A Bayesian Network Analysis of Ethical Behavior

Using one of the major domains of macromarketing – ethics – this paper aims to introduce the Bayesian network (BN) method and demonstrate its added value for macro-level decision makers. Bayesian networks are particularly important for macromarketers because they allow researchers to analyze a domain from a system perspective. The BN approach is considered one of the most powerful tools for observing system changes. The method can also deal with multiple variables at once, which can lead to efficient scenario analyses, critical for understanding how a system functions. As such, BNs offer a powerful tool for macromarketers who deal with systems, interactions, and higher levels of aggregation. We believe that the adoption of this methodology by macromarketing researchers is likely to contribute to the discipline by advancing the understanding of how certain systemic/network relationships and various domains of macromarketing work. © 2015, © The Author(s) 2015

Investigating summer thermal stratification in Lake Ontario

Summer thermal stratification in Lake Ontario is simulated using the 3D hydrodynamic model Environmental Fluid Dynamics Code (EFDC). Summer temperature differences establish strong vertical density gradients (thermocline) between the epilimnion and hypolimnion. Capturing the stratification and thermocline formation has been a challenge in modeling Great Lakes. Deviating from EFDC's original Mellor-Yamada (1982) vertical mixing scheme, we have implemented an unidimensional vertical model that uses different eddy diffusivity formulations above and below the thermocline (Vincon-Leite, 1991; Vincon-Leite et al., 2014). The model is forced with the hourly meteorological data from weather stations around the lake, flow data for Niagara and St. Lawrence rivers; and lake bathymetry is interpolated on a 2-km grid. The model has 20 vertical layers following sigma vertical coordinates. Sensitivity of the model to vertical layers' spacing is thoroughly investigated. The model has been calibrated for appropriate solar radiation coefficients and horizontal mixing coefficients. Overall the new implemented diffusivity algorithm shows some successes in capturing the thermal stratification with RMSE values between 2-3°C. Calibration of vertical mixing coefficients is under investigation to capture the improved thermal stratification

Sustainable Agriculture and Advances of Remote Sensing (Volume 1)

Agriculture, as the main source of alimentation and the most important economic activity globally, is being affected by the impacts of climate change. To maintain and increase our global food system production, to reduce biodiversity loss and preserve our natural ecosystem, new practices and technologies are required. This book focuses on the latest advances in remote sensing technology and agricultural engineering leading to the sustainable agriculture practices. Earth observation data, in situ and proxy-remote sensing data are the main source of information for monitoring and analyzing agriculture activities. Particular attention is given to earth observation satellites and the Internet of Things for data collection, to multispectral and hyperspectral data analysis using machine learning and deep learning, to WebGIS and the Internet of Things for sharing and publishing the results, among others

Assessing the impact of land use change on hydrology and sediment yield in the Xiangxi Catchment (China) using SWAT

This dissertation describes the application of the eco-hydrological model SWAT to a watershed in the Three Gorges Region, which is located in Hubei Province and Chongqing Municipality in Central China. The region is heavily influenced by the construction of the Three Gorges Dam on Yangtze River, which was completed in 2009. The dam was constructed for reasons of flood protection, hydropower production and navigation benefits. It exerts substantial influence on water resources in the affected sub-watersheds of Yangtze River. In the Three Gorges Region, the construction of the Three Gorges Dam induced a large-scale land use change. This can mostly be attributed to the inundation of agricultural areas, villages and towns, which necessitated the resettlement of more than 1 million people and the relocation of agriculturally used areas from the valley bottoms to steep, formerly forested slopes. The clearance of forest on steep slopes and their use for agricultural production is expected to strongly increase the risk of erosion and diffuse sediment inputs to surface waters. Soil erosion results in the removal of nutrient-rich topsoil, which leads to an irreversible degradation of soils and to undesired off-site effects in surface waters. The sediment reduces the life span of the Three Gorges Reservoir due to siltation and carries large amounts of nutrients to the water bodies. At the same time, flow velocities are reduced and the residence time of water is prolonged in the reservoir. In combination, the increasing sediment and nutrient inputs and the altered flow regime are expected to exacerbate the risk of eutrophication and thereby hamper the usability of water resources. Especially in the backwater areas of Yangtze River tributaries, an increasing occurrence of algae blooms has been observed in recent years. The current situation in the Three Gorges Region indicates a strong need for sustainable water resources management. This dissertation aimed at identifying a suitable tool for assessing the impact of land use change in the Three Gorges Region on water quantity and quality to support the development of integrated watershed management plans. Therefore, the eco-hydrological model SWAT (Soil and Water Assessment Tool) was applied to the Xiangxi Catchment in Hubei Province. The Xiangxi Catchment comprises an area of 3200 km2 as is considered to be representative of the eastern part of the Three Gorges Region. Land use in the watershed is dominated by forest. Agriculturally used areas are restricted to relatively small areas, which are characterized by severe soil erosion. SWAT was used in this dissertation to simulate water balance, streamflow and sediment yield under past, current and possible future land use conditions. Also, the most important sources of model error were identified in this study. Results indicate that the model performs very well with regard to streamflow and water balance, whereas the prediction of sediment yield is more problematic. SWAT output was analyzed at different spatial levels ranging from the entire watershed to individual Hydrologic Response Units. Generally, there is considerable uncertainty associated with the SWAT predictions in the Xiangxi Catchment, because of a low amount of data available for model parameterization, calibration and validation. Nevertheless results of the basic model calibration were considered a sufficient basis for the simulation of land use scenarios. The forested area in the Xiangxi Catchment has increased in the recent past which led to a decrease of fast flow components and sediment yield. Scenario simulations demonstrate that a further increase in forest would result in a continuation of the trends observed in the past, whereas an increase of agriculturally used areas would induce a strong increase in sediment yields. The scenario simulations indicate a high potential for conflicts between environmental protection and agricultural production, which is aggravated by conservation efforts of the Chinese government, e.g. the Sloping Land Conversion Program (SLCP). Through compensation and subsidy payments, SLCP encouraged farmers to convert sloping cropland to forest or grassland. While this is an effective means of reducing soil erosion on the afforested areas, it increases the pressure on the remaining cropland. The results of this dissertation suggest that in the future the application of selected Best Management Practices may be more effective for realizing sustainable watershed management plans than continuing to reallocate land use types within the Xiangxi Catchment. SWAT has already been used successfully for assessing the effects of Best Management Practices on water resources in a number of studies. However, the data currently available for the Xiangxi Catchment does not allow for a sufficiently detailed parameterization and calibration of land use and management. Future studies in the Xiangxi Catchment should focus on improving the data base by obtaining additional relevant input data. This can help to reduce the uncertainty in model results and facilitate the simulation of Best Management Practices. By testing the applicability of SWAT to the Xiangxi Catchment and identifying the main sources of uncertainty, this dissertation laid the groundwork for further research in the Three Gorges Region, which can help to preserve natural resources in this unique and sensitive ecosystem