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Managing food-ecosystem synergies to sustain water resource systems النص الكامل
2021
Ward, Frank A. | Salman, Dina | Amer, Saud A.
Measures implemented to restore ecosystem services are widely believed to conflict with food production in the world's irrigated regions because of their competition for scarce water. However, little integrated analysis has been conducted to test this hypothesis. This work tests that hypothesis by presenting results of a basin-scale hydroeconomic analysis linking biophysical, hydrologic, agronomic, ecological, economic, policy, and institutional dimensions of the partially-restored Mesopotamian Marshes of Western Asia. Results serve to partly reject the hypothesis: Here we find that an economically-optimized ecosystem restoration trajectory can be achieved with a minimal loss in food production or farm income where restored wetlands complement important dimensions of food production. Moreover, we find that where water shortage sharing rules can be made more flexible, ecosystem restoration more nearly complements improved food security. Our results point to previously unexplored synergies among food production, ecosystem restoration, and water laws in arid and semi-arid regions internationally.
اظهر المزيد [+] اقل [-]Valuing of Wadi El-Rayan ecosystem through water–food–energy nexus approach النص الكامل
2017
AbdelHady, Rameen S. | Fahmy, Hussam S. | Pacini, Nic
Wadi El-Rayan Protected Area (WERPA) is considered a model protectorate and an ecological restoration success. Development and mismanagement of Wadi El-Rayan vulnerable water resources could lead to the depletion of two artificial lakes and large scale deterioration of ecosystem health. We quantify the environmental value of preserving WERPA by applying the water–food–energy nexus approach and the concept of non-monetary opportunity cost. Three output indicators: agriculture, aquaculture and net energy production are selected to assess the value of different ecosystem health conditions under three water management scenarios. STELLA object oriented modeling environment has been used to simulate the scenarios that led to favorable, satisfactory, and critical ecosystem health conditions. The results demonstrated that the economic output that could be realized by reaching the favorable condition has twice the value of the acceptable condition.
اظهر المزيد [+] اقل [-]Considering agricultural wastes and ecosystem services in Food-Energy-Water-Waste Nexus system design النص الكامل
2019
Garcia, Daniel J. | Lovett, Brittainy M. | You, Fengqi
The Food-Energy-Water-Waste Nexus (FEWWN) represents the interconnections between food, energy, water, and waste production systems, and it has become a key research area. Enormous quantities of agricultural and organic wastes are produced throughout the FEWWN. Often, these wastes are not treated appropriately because their true costs are rarely quantified, and usually externalized to the environment. This shortcoming is addressed from a systems perspective fused with approaches from ecological economics. A regional bioenergy production model where bioenergy may be produced from ethanol and/or agricultural wastes is constructed. Ecosystem service valuation methods are integrated into the framework, allowing for bioenergy production systems to be designed to minimize ecological damage and/or maximize ecological restoration. These values are captured within a Green Gross Domestic Product (Green GDP) objective that values both energy produced and ecosystem service values lost/gained. System profit is another objective in the multi-objective model. The framework is applied to a bioenergy production system for the U.S. state of New York, which aims to produce 10% more bioenergy compared to its current levels. Net changes in Green GDP ranged from -$16.5 M/y to $90.6 M/y, and corresponding profits ranged from $7.2 M/y to -$74.5 M/y. Corn grain ethanol was the dominant source of bioenergy in solutions with higher profits, while ethanol from corn stover and bioelectricity generated from animal manure biogas contributed more bioenergy in solutions with increasing Green GDP. Results show that there is a trade-off between promoting natural capital/ecological health and financial profit. FEWWN system design should consider these trade-offs moving forward.
اظهر المزيد [+] اقل [-]Ecosystem-Based Adaptation Practices as a Nature-Based Solution to Promote Water-Energy-Food Nexus Balance النص الكامل
2021
Muthee, K. | Duguma, L.A. | Nzyoka, J. | Minang, Peter A.
The objective of this study is to evaluate the contributions of ecosystem-based adaptation (EbA) practices to the water–energy–food (WEF) nexus balance, design practical pathways, and analyze barriers towards achievement of EbA-WEF balance. An area case study and descriptive methods were used to analyze data collected from 50 community forests (CFs) spread across three regions in The Gambia. Extensive information from relevant literature sources was also referred to in this study. Fourteen priority EbA practices were established and categorized into four major groups based on their application similarities. Among the anticipated ecosystem services were enhanced water resource conservation, food and feed production, enhanced energy supply, and improved community livelihoods to enhance their resilience. Pathways on how each practice under the broad category contributes to water, energy, and food were developed to demonstrate how they individually and collectively contribute towards the nexus balance. Key enablers identified included a conducive policy framework, institutional support, diverse incentives, information, knowledge, and technology transfer, and climate and non-climate barriers were cited as impediments. The paper concludes by outlining recommendations to overcome the established barriers.
اظهر المزيد [+] اقل [-]Impact of spatial variations in water quality and hydrological factors on the food-web structure in urban aquatic environments النص الكامل
2019
Zhao, C.S. | Yang, Y. | Yang, S.T. | Xiang, H. | Wang, F. | Chen, X. | Zhang, H.M. | Yu, Q.
Global aquatic ecosystems are essential to human existence and have deteriorated seriously in recent years. Understanding the influence mechanism of habitat variation on the structure of the food-web allows the effective recovery of the health of degraded ecosystems. Whereas most previous studies focused on the selection of driving habitat factors, the impact of habitat variation on the food-web structure was rarely studied, resulting in the low success rate of ecosystem restoration projects globally. This paper presents a framework for exploring the effects of spatial variations in water quality and hydrological habitat factors on the food-web structure in city waters. Indices for the evaluation of the food-web structure are first determined by integrating model-parameter extraction via literature refinement. The key water quality and hydrological factors are then determined by coupling canonical correspondence analysis with partial least squares regression. Their spatial variation is investigated using spatial autocorrelation. Finally, fuzzy clustering is applied to analyze the influence of the spatial variations in water quality and hydrological factors on the food-web structure. The results obtained in Ji'nan, the pilot city of water ecological civilization in China, show that the Shannon diversity index, connectance index, omnivory index, and the ratio of total primary production to the total respiration are important indicators of food-web structural change. They show that the driving factors affecting the aquatic food-web structure in Ji'nan are hydrological factors (e.g., river width, water depth, and stream flow), physical aspects of water quality (e.g., air temperature, water temperature, electrical conductivity, and transparency), and chemical aspects (e.g., potassium, dissolved oxygen, calcium, and total hardness). They also show that the stability of the food-web is more prone to spatial variations in water quality than in hydrological factors. Higher electrical conductivity, potassium, total hardness, and air temperature lead to deteriorated food-web structures, whereas better transparency improves structure and stability. We found that water and air temperature are the most important factors in the spatial variation of the food-web structure in the study area, followed by total hardness. Transparency is the least important factor. Large disparities and varied spatial distributions exist in the driving effects of water quality and hydrological factors across regions attributable to differences in geographical environments, water salinity (fresh vs. sea water), and environmental factors (e.g., water pollution). The above methods and results serve as a theoretical and scientific basis for a high success rate of aquatic ecosystem restoration projects in the study area and other cities worldwide.
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