Water Security Problems Research Articles

Analysis of changes in river connectivity during the urbanization process: a case study of the southeastern plain of Yinzhou, China.

Affected by human activities, the naturally occurring river network in the southeastern plain of Yinzhou has gradually evolved into a natural-artificial composite water system, and changes in river connectivity due to changes in river network systems have caused water security problems, including urban flooding. To clarify the river connectivity change and its relationship with the urbanization process, this paper discusses an evaluation method for river connectivity based on complex networks and cellular automata (CA) from the perspective of complex systems, quantitatively analyzes the spatial-temporal characteristics of the structural and functional river connectivity in the study area during the 1990s-2020s, and reveals the impact of river nodes and chains on the connectivity level under the disturbance of natural or human factors. The results contained the following revelations: ① River connectivity showed a decreasing trend in the initial and rapid development stages of urbanization from the 1990s to the 2010s and a limited increasing trend in the optimization and upgrading stages from the 2010s to the 2020s. ② River network degradation and ongoing connectivity decline are found in the northeastern part of the study area. The highest river connectivity exists in Dongqianhukaifaqu. ③ The number of river nodes and chains should be maintained at approximately 80% for normal river connectivity. The nodes of high degree in the inflow area are listed in the key protection areas. ④ Changes in river connectivity are significantly correlated with the urbanization process. Changes in the functional connectivity level affect the magnitude of a flood. This study provides a theoretical basis for river network connectivity improvement and flood prevention in plain areas.

A Harmony-Based Approach for the Evaluation and Regulation of Water Security in the Yellow River Water-Receiving Area of Henan Province

Water security, as a crucial component of national security, plays a significant role in maintaining regional stability and ensuring the healthy and rapid development of the economy and society. The Yellow River water-receiving area of Henan Province (YRWAR-HN) is selected as the research area in this study. Firstly, a comprehensive evaluation index system is constructed based on the actual water security problems of the research area, and the single index quantification–multiple indices syntheses–poly-criteria integration method (SMI-P) is introduced to quantify the water security degree of 14 cities in the YRWAR-HN from 2010 to 2021. Then, the obstacle degree model is used to identify the key obstacle indexes that restrict the improvement of water security. Finally, the harmonious behavior set optimization method is adopted to carry out the regulation of water security, and the improvement path of water security in the YRWAR-HN is formulated. The results indicate the following: (1) the water security degree of the YRWAR-HN shows a fluctuating upward trend, increasing from 0.4348 (2010) to 0.6766 (2021), a significant rise of 55.61%. The water security level improves from the relatively unsafe level to the relatively safe level. Hebi City exhibits the fastest rate of water security improvement, while Xinxiang City shows the slowest rate. (2) The density of the river network (X1) and the proportion of investment in water conservancy and environmental protection in the total investment (X15) are the two indexes with the highest obstacle degree, with the average obstacle degrees being 15.09% and 10.79%, respectively. (3) The combination of the composite regulation scenario and improvement Path 2 is the optimal regulation strategy for water security in the YRWAR-HN. From the implementation process, Luoyang, Sanmenxia, Jiyuan, Xuchang, and Shangqiu may prioritize improving their flood and drought disaster defense capabilities and emergency response capabilities, continuously enhancing the flood prevention and disaster reduction system. Zhengzhou, Kaifeng, Xinxiang, Jiaozuo, Anyang, Hebi, Pingdingshan, and Zhoukou may prioritize resolving the regional water supply and demand conflicts, balancing development and conservation, actively seeking transboundary and external water transfers, and strengthening the capacity for water conservation and intensive utilization. Puyang City may prioritize enhancing its comprehensive water environment management capabilities, increasing investment in water conservancy and the environment, improving production processes, reducing pollutant emissions, and mitigating agricultural non-point source pollution.

Evaluation and prediction of water security levels in Northwest China based on the DPSIR model

Since the the dawn of the 21st century, water security has occupied a pivotal position in fostering sustainable development. However, frequency of extreme weather events due to climate change and higher intensity of anthropogenic events, water security problems in Northwest China are becoming increasingly prominent. This paper elucidates water security levels and predicts future trends of Northwest China. Firstly, the Driving Force-Pressure-State-Impact-Response (DPSIR) conceptual framework served as the foundation for the establishment of the water security evaluation index system. Then used the entropy weight method to calculate the weight of indicators and the five-element connection degree method was used to assess the water security levels. The period for the data used in the study was from 2010 to 2019. Finally, a grey prediction model was employed to forecast the water security levels from 2023 to 2030. The findings showed that: (1) From 2010 to 2019, the water security situation gradually developed to a very high level in Northwest China: Shaanxi Province mostly attained a high level, and the water security grades of Ningxia Hui Autonomous Region and Xinjiang Uygur Autonomous Region were mostly at a very low level. (2) Generally, from 2023 to 2030, the water security level will continue to improve. The water security grades of Shaanxi, Gansu, and Qinghai will mostly be at the medium level, while that of Ningxia Hui Autonomous Region and Xinjiang Uygur Autonomous Region will be at the low level. (3) The five dimensions of water security in Northwest China demonstrated a fluctuating yet consistently upward trend. (4) Based on the results, suggestions were put forward regarding water security and sustainable development in Northwest China.

Water Security Problems of Lake Tana and Its Possible Management Options: A Review

Lake Tana is the largest lake in Ethiopia and accounts for 50% of the country's freshwater resources. It provides a unique habitat for biodiversity and plays an economic role via tourism, electricity, agriculture, fishery, and, most importantly, it provides drinking water to the local inhabitants. Because of its immense water resource potential for socioeconomic development, Lake Tana has been identified as a major economic corridor in the country. Given the importance of the lake to the region and nation’s economy, human health, and livelihoods, assessing the water security problems of the lake in terms of water scarcity and quality is critical for its sustainable management. Doing so, studies on water level fluctuation and water scarcity, and physicochemical and related hydrological and biological features of the lake, which have been reported in the literature over more than a decade, were reviewed, and the studies showed that water level fluctuation was observed and resulted in water scarcity problems for surrounding communities. In addition to water scarcity and water fluctuation problems, the lake's trophic status has also gradually changed from oligotrophic to mesotrophic and eutrophic. In addition, faecal pollution, heavy metal pollution, and toxicogenic cyanobacteria are detected in the lake, especially on the shores and its tributary river mouths. Moreover, Lake Tana is infested by the ecologically dangerous and worst invasive weed, the so-called water hyacinth, with rapid area coverage and has resulted in dominant other important floras and posing a significant negative impact on water quality, biodiversity, fishing, water supply, water transportation, and other economic activities. There are options recommended to manage the lake. In this regard, different lake ecosystem management options like delineation of buffer zones, integrated watershed management, awareness creation about the lake and its associated wetlands, development of waste management practices, eradicating/reducing water hyacinth, and enforcement of environmental related policies and Strategies are recommended for sustainable management of Lake Tana.

Diagnosis and Evolution Characteristics of Critical Water Security Problems in the Source Region of the Yellow River

Diagnosis and Evolution Characteristics of Critical Water Security Problems in the Source Region of the Yellow River

Adaptive management of water resources system in the arid Aksu river basin, northwest China

Due to changing environments, the conflict between water supply and demand in arid northwest China is becoming increasingly prominent, resulting in the water security challenges and the need for risk management. Therefore, this study aimed at developing an adaptive management approach for the compound systems of water ecology and socioeconomics in the Aksu River Basin (ARB), a typical northwest arid watershed in China. This strategy aimed to reduce risk based on an adjusted water resource management system with the stringent controls (i.e., total water consumption, water use efficiency, and minimum ecological water satisfaction rate controls ‘three red lines’). The main findings are as follows: (1) Although the water resource system in the ARB is currently at low risk state, it could be subjected to higher risk levels in future scenarios. (2) An adjusted “three red lines” policy should be utilized to ensure adaptive management of risk in the water resource system. The corresponding coefficients for each “red line” was 8.37, 10.78, and 0.609, respectively. (3) Following a nonlinear multi-objective management, the vulnerability and risk decreased significantly, by −100% and −50%, respectively, whereas the resilience of the water resource system increased significantly, up to 330%. Therefore, adaptive water resource management is vital in reducing water resource risk, and is important for understanding the status of regional water resource systems and solving water security problems in a changing environment.

Multi-scale near-long-range flow measurement and analysis of virtual water in China based on multi-regional input-output model and machine learning

At present, China is facing a relatively serious water security problem, and virtual water trade is an important means to alleviate the shortage of water resources. It is of great practical significance for China to analysis of the multi-scale near-long-distance flow of virtual water between regions. In this paper, the multi-regional input-output model was used to measure the virtual water near-long-range transfer of 17 departments in eight regions in 2012 and 2017 in China. The measured results are further discussed in the context of K-means and structural decomposition analysis (SDA) methods. The results show that from 2012 to 2017, the overall trend of interregional virtual water flow and import and export volume of various regions and departments in China showed a downward trend, and there were significant differences in inflow, outflow, and distribution. In 17 sectors, the agricultural sector has a much higher virtual water flow than other sectors, particularly in the north-west and central regions. In addition, the food and tobacco industry and construction industries in most regions also have the characteristics of high outflows. This paper argues that China should Fully exploit the effect of industrial structure on the suppression of virtual water rise. At the same time, it is necessary to improve the virtual water trade pattern, especially the virtual water trade pattern of the agricultural sector, and then gradually optimize the distribution pattern of regional water resources in China.

Unpacking the urban virtual water of the Global South: Lessons from 181 cities

Most of the water humanity currently consumes is invisible, it is embedded within goods and services purchased by final consumers from the global economic market. Cities of the Global South (GS) – especially African and Asian cities are facing twofold water security problems. First, the increased risk of water availability (both quantity and quality), which is exacerbated by climate change. Second, the ever-increasing water demand due to their economic and population growth. Therefore, to help cities of the GS to efficiently manage their water resources, it is crucial to explore what products are being imported from the global economic market and assess their embodied water intensities. Herein, the water footprints (blue and grey) of 181 cities from the GS are computed using Extended Environmental Input-Output Analysis (EE-IOA). Results point out that water imports through virtual water are significant and growing even across the GS with different magnitudes because of the economic attributes of cities (expenditures patterns) and their geography (spatial location). The average blue virtual water is estimated to be 253 l per capita/yr and 285 l per capita/yr for virtual grey water. When decomposing the water footprint we found that the major responsible sectors are “Food” accounting for 37% of the total footprint, followed by “Transport” with 24%, and “Energy” with 22%. To put the climate impacts in perspective, cities of the GS must act in a proactive approach and use the water-trade nexus as a supplementary approach to shape and implement water security strategies.

Theory and Practice of Hydrodynamic Reconstruction in Plain River Networks

The river networks in the plains of China are in low-lying terrain with mild bed slopes and weak hydrodynamics conditions. Filled with intense human activities, these areas are characterized by serious water security problems, e.g., frequent floods, poor water self-purification capabilities, and fragile water ecosystems. In this paper, it’s found that all these problems are related to hydrodynamics, and the spatiotemporal imbalance of river network hydrodynamics is identified as the common cause of these water-related problems. From this, a theory for the hydrodynamic reconstruction of plain river networks is proposed. In addition to the importance of the flow volume, this theory highlights the role of hydrodynamics and limited energy in improving the ecological water environment. The layout of water conservancy project systems (e.g., sluices and pumping stations) is optimized to fully tapping the potential integrative benefit of projects. The optimal temporal and spatial distributions of hydrodynamic patterns is reconstructed in order to meet the needs of the integrated management of complex water-related problems in river networks. On this basis, a complete theoretical method and technical system for multiscale hydrodynamic reconstruction and multi-objective hydraulic regulation in plain river networks with weak hydrodynamics is established. The principles of the integrated management of water problems in river network areas are put forward. The practical application and efficacy of the theory are demonstrated through a case study aiming to improve the water quality of the river network in the main urban area of Yangzhou City.

An Extended Interval Type-2 Fuzzy VIKOR Technique with Equitable Linguistic Scales and Z-Numbers for Solving Water Security Problems in Malaysia

Interval Type-2 Fuzzy VIseKriterijumska Optimizacija I Kompromisno Resenje (IT2FVIKOR) technique is one of the techniques of Interval Type-2 Fuzzy Multi-Criteria Decision Making (IT2FMCDM), which was developed to solve problems involving conflicting and multiple objectives. Most of the IT2FVIKOR methods are created from linguistic variables based on Interval Type-2 Fuzzy Set (IT2FS) and its generalization, such as Interval Type-2 Fuzzy Numbers (IT2FNs). Recent literature suggests that equitable linguistic scales can offer a better alternative, particularly when IT2FSs have some limitations in handling uncertainty and imbalance. This paper proposes the extended IT2FVIKOR with an equitable linguistic scale and Z-Numbers, where its linguistic scale introduces an equitable balance of positive and negative scales added to the restriction and reliability approach. Different from the typical IT2FVIKOR, which directly utilizes IT2FNs with a positive membership, the proposed method introduces positive and negative membership where each side considers a restriction and reliability approach. Besides, this paper also offers objective weights using fuzzy entropy-based IT2FS to calculate the weights of the extended IT2FVIKOR. The obtained solutions would help decision makers (DMs) identify the best solution to enhance water security projects in terms of finding the best strategies for water supply security in Malaysia.

An analysis of finding the best strategies of water security for water source areas using an integrated IT2FVIKOR with machine learning

Worldwide, water security is adversely affected by factors such as population growth, rural–urban migration, climate, hydrological conditions, over-abstraction of groundwater, and increased per-capita water use. Water security modeling is one of the key strategies to better manage water safety and develop appropriate policies to improve security. In view of the growing global demand for safe water, intelligent methods and algorithms must be developed. Therefore, this paper proposes an integrated interval type-2 Fuzzy VIseKriterijumska Optimizcija I Kompromisno Resenje (IT2FVIKOR) with unsupervised machine learning (ML). This includes IT2FVIKOR for ranking and selecting a set of alternatives. Unsupervised machine learning includes hierarchical clustering, self-organizing map, and autoencoder for clustering, silhouette analysis and elbow method to find the most optimal cluster count, and finally Adjusted Rank Index (ARI) to find the best comparison within two clusters. This proposed integrated method can be divided into a two-phase fuzzy-machine learning-based framework to select the best water security strategies and categorize the polluted area using the water datasets from the Terengganu River, one of Malaysia’s rivers. Phase 1 focuses on the IT2FVIKOR method to select five different strategies with five different criteria using five decision makers for finding the best water security strategies. Phase 2 continues the unsupervised machine learning where three different clustering algorithms, namely, hierarchical clustering, self-organizing map, and autoencoder, are used to cluster the polluted area in the Terengganu River. Silhouette analysis is applied along with the clustering algorithms to estimate the number of optimal clusters in a dataset. Then, the ARI is applied to find the best comparison within the original data with hierarchical clustering, self-organizing map, and autoencoder. Next, the elbow method is applied to double-confirm the best clusters for each clustering algorithm. Last, lists of polluted areas in each cluster are retrieved. Finally, this 2-phase fuzzy-Machine learning–based framework offers an alternative intelligent model to solve the water security problems and find the most polluted area.

ОСОБЕННОСТИ СЕКЬЮРИТИЗАЦИИ ВОДНОГО ВОПРОСА В ЭФИОПИИ В РАМКАХ КРИТИЧЕСКИХ ПОДХОДОВ К ИССЛЕДОВАНИЮ БЕЗОПАСНОСТИ

This article seeks to explore the problem of water security in Ethiopia, involving the implementation of the Grand Ethiopian Renaissance Dam (GERD) project. With its existential significance for the Ethiopian nation attributed to the dam, discovering the mechanisms of constructing threats to water security, as well as possible structural preconditions for a shift from confrontational to compromise politics, are examined. Therefore, an analysis of the Ethiopian discourse on GERD is being carried out in order to identify possible signs of securitisation and / or de-securitisation of the water issue. The research also compares the explanatory power of various approaches within the theory of securitisation for this case. The key finding is the explanation of the phenomenon of water securitisation in Ethiopia as an established political technology for the management of internal processes, in contrast to the traditional approach which posits an intersubjective policy of decisive action.

Water Security in Egypt amid the Crisis around the Renaissance Dam in Ethiopia

The article is devoted to the study of the problem of water security in Egypt, associated with the implementation of the Ethiopian Renaissance Dam (GERD) project. GERD raises serious concerns on the part of Egypt because of the possible reduction in the Nile River flow, which could lead to an economic and social crisis. In the context of the politicization of the water issue, the negotiation process to resolve it is complicated. Therefore it is important to find out whether it is possible to shift its perception from a threat to security to the possibility of mutually beneficial cooperation. Giving GERD an "existential" meaning for Egypt led to the use of the concept of securitization, according to which threats are created and deconstructed solely through speech acts. In order to clarify the prospects for resolving the water dispute with Ethiopia, an analysis of both the political and expert discourse of Egypt in relation to GERD is made. The main result was to explain the phenomenon of water securitization in Egypt as a stable political technology for managing internal processes, in contrast to the traditional approach to securitization as a policy of decisive action. This technology is the regulation of public fears by using the "resource argument" in order to reduce internal instability. The possibility of softening Egypt's position in the negotiation process on GERD and reducing the severity of the perception of the water issue depends mainly on the improvement of the socio-economic situation in the country.

Research on Prefabricated Road base Technology under the concept of Sponge City

The problems of construction period, quality and coordination between road construction and maintenance and road traffic often exist in the process of traditional urban road construction. The development of urbanization has brought about the rapid expansion of urban roads, and the changes in the permeability of urban underlying surface have also brought about urban waterlogging and urban water security problems. Making full use of the environmental protection, high efficiency and economic characteristics of the prefabricated process, through data investigation, theoretical calculation and mechanical analysis as the main means, the prefabricated prefabricated road base is studied and designed, drawing on the stress characteristics of the raft foundation of the building structure and the concept of beam and slab force transmission, forming the prefabricated beam and slab base in the form of raft structure, taking into account the actual drainage capacity of the urban pipe network and the outdoor drainage regulations, and setting drainage holes and gravel layers, Make the prefabricated road base have the function of organized drainage and water storage at the peak of runoff, so as to alleviate urban waterlogging to a certain extent and solve urban water safety problems.

Comprehensive Evaluation on Urban Water Security Based on the Novel DPEBLR Concept Model and the Cloud Matter-Element Model: A Case Study of Chongqing, China

Urban water security problems such as water scarcity, water pollution, and flood disasters have restricted the sustainable development of cities. In order to scientifically evaluate the urban water security situation, this study combined the DPSIR (driver, pressure, state, impact, response) model and HEVD (the hazard of disaster-causing factors, the vulnerability of disaster-affected bodies, the instability of the disaster-pregnant environment, and population loss) model to propose a new conceptual framework for DPEBLR (driver, pressure, environment, insecurity-affected body, loss, response). Based on this conceptual framework, 35 indicators were selected to establish an urban water security evaluation index system. In order to solve the problem of randomness and fuzziness of the boundary values of urban water security classification levels, the cloud matter element model was applied. Chongqing was used as an example for verification, and the results showed that the water security status of Chongqing City improved from 2011 (Ⅴ) to 2019 (Ⅱ). This indicates that the water ecology restoration project, centralized water source protection project, centralized water supply project, water-saving society transformation, and flood and drought prevention system construction project implemented in Chongqing has achieved significant results. However, Chongqing still faces the problem that the construction of an urban flood control system cannot meet the speed of urban development. The government should slow down the urbanization and allow the urban flood control system to be ready before the area is occupied. In addition, the awareness of water conservation for industrial use in Chongqing has been formed, and citizens’ awareness of water conservation for domestic use should be enhanced in the future.

Sources and migration similarly determine nitrate concentrations: Integrating isotopic, landscape, and biological approaches

Rapid land use change has significantly increased nitrate (NO3−) loading to rivers, leading to eutrophication, and posing water security problems. Determining the sources of NO3− to waters and the underlying influential factors is critical for effectively reducing pollution and better managing water resources. Here, we identified the sources and influencing mechanisms of NO3− in a mixed land-use watershed by integrating stable isotopes (δ15N-NO3− and δ18O-NO3−), molecular biology, water chemistry, and landscape metrics measurements. Weak transformation processes of NO3− were identified in the river, as evinced by water chemistry, isotopes, species compositions, and predicted microbial genes related to nitrogen metabolism. NO3− concentrations were primarily influenced by exogenous inputs (i.e., from soil nitrogen (NS), nitrogen fertilizer (NF), and manure & sewage (MS)). The proportions of NO3− sources seasonally varied. In the wet season, the source contributions followed the order of NS (38.6 %) > NF (31.4 %) > atmospheric deposition (ND, 16.2 %) > MS (13.8 %). In the dry season, the contributions were in the order of MS (39.2 %) > NS (29.2 %) > NF (29 %) > ND (2.6 %). Farmland and construction land were the original factors influencing the spatial distribution of NO3− in the wet and dry seasons, respectively, while slope, basin relief (HD), hypsometric integral (HI), and COHESION, HD were the primary indicators associated with NO3− transport in the wet and dry seasons, respectively. Additionally, spatial scale differences were observed for the effects of landscape structure on NO3− concentrations, with the greatest effect at the 1000-m buffer zone scale in the wet season and at the sub-basin scale in the dry season. This study overcomes the limitation of isotopes in identifying nitrate sources by combining multiple approaches and provides new research perspectives for the determination of nitrate sources and migration in other watersheds.

Agricultural water security from the perspective of critical theory paradigm

Ensuring the security of freshwater resources is one of the most important drivers of the quality of social and environmental systems. In recent years, the security of water resources has faced various challenges. In other words, the water resources have become more vulnerable to threats and there is more concern about the sustainable development of socio-environmental systems. The significance of water security and associated concerns have led many researchers to conceptualize the water security and design indices to measure it. The worrying situation of the water security suggests that traditional philosophical paradigms, because of the way they look at man and nature, cannot be successful in solving the problems of agricultural water insecurity. In this regard, it is necessary to look for a new paradigmatic perspective to solve this crisis. In this paper, which was written using a review and analytical study, an attempt was made to examine and compare the concept of water security from the perspectives of positivism, constructivism, and critical theory. In addition, indicators of the critical theory paradigm were introduced and their ability to help conceptualize agricultural water security was explored from a critical theory perspective. The indicators of the critical theory paradigm include: inclusion, communication, cosmopolitanism and change. Also, the concept of agricultural water security from the perspective of critical theory is the emancipation of vulnerable farmers from various communicational, political, social, sexual, economic, and natural barriers. In this process, they will be able to freely participate in water decision-makings and be able to change the existing conditions to the desired conditions. Overall, the results showed that the critical theory paradigm, because of its point of view to the man and nature, as well as its goals of emancipation and change, could be a solution to the complex problems of agricultural water security.

Water footprint of food production and consumption in China

Abstract A comprehensive understanding of water for food production and consumption is an essential part of achieving sustainable water use. Water footprint is an effective tool to analyze the problems of water and food security. The study analyzed the food production and consumption water footprint of 12 major products from the points of spatial, temporal and structure, including plant-based food and animal food. From 2001 to 2019, the production and consumption water footprint presented an upward trend and almost a three-fold difference between the two. In terms of spatial pattern, the high values were mainly concentrated in eastern China. The water stress level and water footprint of food production basically coincided. However, there seemed to be no significant correlation with water footprint of food consumption. Referring to the great variation in water structure, green water was the dominant not only in food production, but also in consumption. For food structure, grain production and consumption contributed the most to the overall water footprint. Finally, the study put forward suggestions for sustainable food production and consumption. The research is helpful to realize green and efficient water management in the food production process and rational consumption, ensuring food and water security. HIGHLIGHTS The water footprint of food production and consumption of 12 major foods is explored from three aspects: spatial-temporal differences, water resources structure and food structure. There was a three-fold difference between the water footprint of food production and consumption. Green water accounted for the highest proportion of food production and consumption. Food and vegetable production and food and meat consumption had a high water footprint.

Carbon Budget of Paddy Fields after Implementing Water-Saving Irrigation in Northeast China

Water-saving irrigation is recognized as an effective agricultural management due to water security and environmental protection problems. In Northeast China, an increasing number of paddy fields are shifting from conventional irrigation to water-saving irrigation. However, there is limited knowledge regarding the carbon (C) budget of paddy fields after implementing water-saving irrigation in Northeast China. A 2-year consecutive field study was performed from 2018 to 2019 using three different irrigation regimes (conventional irrigation (FI), controlled irrigation (CI), and intermittent irrigation (II)) and two nitrogen (N) fertilization levels (110 and 165 kg N ha−1) in a paddy field of Northeast China. The present study aimed to quantify the net ecosystem C budget (NECB) and net global warming potential (net GWP) after the implementation of water-saving irrigation in Northeast China. Both CI and II enhanced the C sequestration capacity of this paddy field. The net primary productivity (NPP) under CI and II was higher than FI by 18–38% and 11–33%, respectively, when the same N fertilization level was applied. The NECB ranged from 1151 to 2663 kg C ha−1, indicating that all treatments acted as net C sinks. II increased the NECB through increasing NPP, which exceeded increased removal of harvest and C mineralized losses. Under II, the NECB was significantly higher than FI and CI when the same N fertilization level was applied (p < 0.05). The net GWP under II and CI was significantly lower than FI (p < 0.05). The net GWP under II was lower than CI when the N fertilization level was 165 kg N ha−1, but no significant differences were detected. These results demonstrated that the II with 165 kg N ha−1 of paddy fields strongly decreased net GWP in Northeast China to combat global climate change.

Impacts of Water and Energy Sector Reforms in Gujarat: The Case of Expansion of Micro Irrigation Schemes and Rationalisation of Agricultural Power Tariff

Against the backdrop of the water and energy sector reforms enunciated by the state government in Gujarat, this paper reviews the important policy changes and outcomes of farm-level adoption of water-saving technologies, on the one hand, and the effective implementation of energy tariff policies, on the other hand. Following an assessment of the water and energy policy and regulatory interventions, the paper provides an overview of the farm-level adoption micro irrigation (sprinkler and drip irrigation) systems over the past one decade of the policy reforms. The paper then examines the case of energy sector reforms enunciated by the state in coordination with the energy regulator through establishment of the distribution companies (DISCOMs). The paper brings out that the policy and regulatory interventions in the water and energy (power) sectors have been successful in terms of wider promotion of micro irrigation systems and deregulation of power generation and distribution activities by establishing dedicated DISCOMs. Thus, the policy initiatives were able to address several challenges facing the water and energy sectors in the state. Firstly, the wide-scale promotion of micro irrigation schemes has significantly reduced the groundwater over-extraction for agriculture. Second, the energy sector reforms have shown a significant progress towards rationalisation of tariffs across sectors. However, it emerges that the policy and regulatory reforms need to (i) go beyond the narrow confines of promotion of micro irrigation systems towards sustainable management of water resources and (ii) move beyond rationalisation of power tariffs by offering sustainable solutions to the problems of water and energy security amidst increasing competition for inter-sectoral allocations. Essentially, the energy sector policies and reforms may explore the potential of renewable energy sources through decentralised investments in solar and wind energy systems in the rural areas involving different public–private community partnership models.