Water Management Technologies Research Articles

Development of multidimensional food security index for Rajasthan, India: A district-level analysis

ABSTRACT The present study tries to analyze the status of food security and its various components, such as food availability, accessibility, stability, and utilization with the help of a multidimensional index across districts in Rajasthan, India, based on an indicator approach. The results confirm that there is a wide range of inequalities in terms of food security across districts. The Jaipur was found to be the most food-secure in Rajasthan due to relatively higher food accessibility. Conversely, lower food availability and accessibility contributed to the lowest food security in Banswara. Hence, study recommends: (i) diversification from farm to nonfarm activities; (ii) sufficient storage capacity to control price fluctuations throughout the year; (iii) promotion of water management and conservation technologies; (iv) regulation and replenishment of groundwater in rural areas for augmenting cropping intensity; (v) district-specific policies to arrest food insecurity; and (vi) strengthening the coverage of the rural employment program, i.e. MGNREGA.

Mitigating risks of hybrid rice use in terrace agriculture

The Honghe Hani Rice Terraces of Yunnan Province have become a national emblem for China and a UNESCO World Heritage Site, but some are beginning to crumble. This research attempts to address why this is happening and what can be done about it. Previous work has failed to adequately address the possible shortcomings of recently introduced seed and water management technologies, their particular effect on rice terraces and the people who depend upon them. In an effort to better understand the issue, field observation was triangulated with in-depth interviews with local people, and the examination of scientific literature. To do this, the authors spent time in China with a translator in a key village known to be first in the area to truly succeed in carving the rice terraces and in making the mountain slope irrigation system required actually working. Results validated by experts in each field indicate that while the new seed and technologies do save water and improve lives, paired with migration, they may also be threatening the long-term viability of rice terracing in the region. The authors conclude that an integrated approach is needed and put forward a strategic blueprint to reinforce ecological, social and economic longevity. They also call for more research into the applicability of these resilience measures in other hybrid rice terracing regions, such as in the Philippines and Vietnam.

Experimental and simulation analysis of liquid capillary fingering process in the gas diffusion layer

In a proton exchange membrane fuel cell (PEMFC), water movement through the gas diffusion layer (GDL) is essential for water management. Using a combination of experiments and simulations, this paper investigates the capillary fingering process of liquid water within the GDL and analyzes the effects of flow field type, GDL compression ratio, and contact angle on the capillary fingering of liquid water within the GDL. The results reveal finger-stopping, splitting, and fusion during the injection of non-wetting liquid, which is not conducive to rapid water movement within the GDL. When water breaks through the top layer of the fibers, a finger path between the inlet and the gas channel is formed, and the liquid preferentially migrates along this path. Due to the existence of air cross-flow, the GDL water saturation for the serpentine/cross-finger flow field is 17.2%. The water preferentially produces directional flow in the through-plane direction as the compression ratio rises, and the GDL water saturation falls to 24.18%. The distribution of anisotropic contact angles determines the flow state of liquid water, making water removal from the GDL easier. The results and findings here are expected to lead to more reliable water management and related high-power technologies of PEMFCs.

Optimal Water Level Management for Mitigating GHG Emissions through Water-Conserving Irrigation in An Giang Province, Vietnam.

Rational water and fertilizer management approaches and technologies could improve water use efficiency and fertilizer use efficiency in paddy rice cultivation. A promising water-conserving technology for paddy rice farming is the alternate wetting and drying irrigation system, established by the International Rice Research Institute. However, the strategy has still not been widely adopted, because water level measurement is challenging work and sometimes leads to a decrease in the rice yield. For the easy implementation of alternate wetting and drying among farmers, we analyzed a dataset obtained from a farmer's water management study carried out over a three-year period with three cropping seasons at six locations (n = 82) in An Giang Province, Southern Vietnam. We observed a significant relationship between specific water level management and the rice yield and greenhouse gas emissions during different growth periods. The average water level during the crop period was an important factor in increasing the rice yield and reducing greenhouse gas emissions. The average water level at 2 days after nitrogen fertilization also showed a potential to increase the rice yield. The greenhouse gas emissions were reduced when the number of days of non-flooded soil use was increased by 1 day during the crop period. The results offer insights demonstrating that farmers' implementation of multiple drainage during whole crop period and nitrogen fertilization period has the potential to contribute to both the rice yield increase and reduction in greenhouse gas emissions from rice cultivation.

Introduction of advanced water management technologies in the Orenburg mining region

The Orenburg Region is rich in various minerals. Dozens of oil and gas fields are being developed on its platform sediment part, while the mountain-folded areas hold deposits of non-ferrous, ferrous and precious metals, rare and radioactive elements, bituminous coal and lignite, and non-metallic minerals. Huge land areas are disturbed by mining, occupied by stock piles of waste rocks and lowgrade ore, and are polluted with spills of oil and deep brines. The economic development of the region is accompanied with an increase in pollution and depletion of water resources. Wide distribution of alkaline land, saline-alkali soils and granitoids containing radon and toxic products of its decay aggravates the impact on the regional hydrosphere. In this regard, it is necessary to study the complex hydrogeology in the region and to evaluate the water quality. The important problems to be solved include: development of the reservoir appraisal methodology; chemical and bacteriological analysis of water and its sensitivity to secondary salinization processes and relics of the marine salt complex; substantiation of water spreading and contamination prevention technologies. The developed recommendations are meant to reach the objective of introduction of modern water management technologies into production as per the resolution of the Russian Government. The article discusses feasibility of water management technologies as a case-study of the Svetly district of the Eastern Orenburg region and the Orenburg urban agglomeration, and necessitates recommendations for their implementation under diverse conditions within the Orenburg Region. As a result of the methodological approach, calculations and modeling of the situation in the mining areas of the Orenburg Region, the effectiveness of the technology of water spreading by means of accumulation of flood water in the local river is proved. The water spreading approach using the active water intakes and conservation reservoirs can increase the productivity of operating wells by 1.5–2 times, enable avoiding depletion of the aquifer and allow meeting the needs of the Orenburg Region’s population in drinking water.

Comprehensive improvement of soil quality and rice yield by flooding-midseason drying-flooding.

Many water-saving technologies have been developed to reduce water input and the associated irrigation costs. However, the influence of water management technologies on soil quality is unclear. Soil quality is fundamental to rice yield and sustainable productivity of ecosystems. Therefore, it is important to understand the effect of water management on soil quality and its linkage with rice yield. In this work, a field experiment was conducted to assess the influence of water management on soil physico-chemical properties, microbial biomass, bacterial community, and rice yield in paddy fields. Three water treatments were selected for the study, including flooding-rain-fed (F-RF), flooding-midseason drying-flooding (F-D-F), and continuous flooding (CF). Total nitrogen (TN), total phosphorus (TP), dissolved carbon content (DOC), available phosphorus (AP), nitrate nitrogen (NO3-), microbial biomass carbon (MBC), and microbial biomass nitrogen (MBN) contents were 11%, 20%, 29%, 30%, 11%, 183%, and 215% higher in F-D-F, respectively, than those in the CF (p < 0.05). Additionally, the bacterial diversity in F-D-F and CF was significantly higher compared to the F-RF (p < 0.05). Correspondingly, soil quality index (SQI) was higher in the F-D-F (0.8) than that of F-RF (0.53) and CF (0.5). Compared with the F-RF, water management remarkably altered bacterial community composition, with higher enrichment of anaerobic bacteria (such as Firmicutes and Chloroflexi) in flooding treatments (CF and F-D-F). Differences in the bacterial community were closely related to key soil quality indicators, such as AP. Parallel increases in soil quality and bacterial diversity resulted in increased rice yield in the F-D-F, which was 53% and 12% higher than that in F-RF and CF, respectively. Therefore, F-D-F is the suggested water management method because it can comprehensively improve soil microbial diversity, soil quality, and rice yield. KEY POINTS: • Water management changed bacterial community mainly via SMC (soil moisture content), TP, AP, and NO3-contents. • The F-D-F had greater SQI and higher rice yield in comparison with F-RF and CF.

Optimising Water Management in Drylands to Increase Crop Productivity and Anticipate Climate Change in Indonesia

In the future, Indonesia will become increasingly dependent on dryland agriculture. New adaptive technology innovations able to transform drylands into arable land throughout almost the entire year have been developed to anticipate global climate change in tropical areas. This article reviews the results of research on the importance of climate and water management technology to increase the crop index and productivity in Indonesia. We found that irrigation treatment at 80% of the FAO-recommended rate resulted in the highest maize stover yield (around 13.65–14.10 t h−1). Irrigation treatment at 60% of the FAO-recommended rate for soybeans (at 0.24 L s−1 h−1) produced good-quality soybean seeds. The use of existing water resources can increase the planted area from 1.25 to 1.67 and increase the cropping index during the second planting season in the same area. Agricultural systems based on water management can improve their crop index and productivity, and anticipate climate change to increase farmers’ incomes and wellbeing. Support measures in the form of regulations, legislation, acts, programmes, and policies from central and local governments for land use and management are crucial. The development of infrastructure by establishing water management institutions at the village/farmers’ group levels to allocate irrigation water is a leverage point to develop dryland agricultural systems appropriately and judiciously to assist in sustainable development.

Study of Methane Gas Emissions from Agricultural Activities and its Coping Strategies in Bedog Sub-watershed

Food production through agricultural activities needs to be intensified to meet food demand. Agricultural activities can also emit methane (CH4) emissions and thus contribute to climate change. Assessing agricultural activities can be done by measuring CH4 emissions, which we implemented in the Bedog Sub-watershed. The purposes of this paper are (1) to calculate CH4 emissions from agricultural activities, and (2) to propose strategies to deal with CH4 emissions. Emissions calculation was done by using IPCC 2006 framework. The mapping results of agricultural area in 2015 and 2020, which consists of rice field area and rice variety, were used in this study, along with Tier 1 IPCC factor. The results of this study show (1) the value of CH4 emissions from rice fields in 2015 was 0.73 Gg CH4/year and decreased by 0.64 Gg CH4/year in 2020. Meanwhile, methane emissions from animal husbandry were 0.35 Gg CH4/year in 2020. This decrease was caused by land-use change in the Bedog Sub-watershed. (2) Theoretically, adaptation and mitigation strategies that can be implemented in the Bedog sub-watershed are the technology for water management and farming, capacity building, determining the appropriate variety and feed, fertilizing, regulating water regimes, method of tillage, and processing biogas.

A Comprehensive Review of the Potential of Stepwells as Sustainable Water Management Structures

Throughout history, many water conservation and management strategies have been employed, but only a few have proved successful. Stepwells were one such effective water management technologies used in India. Stepwells were constructed based on their geographical and topographical suitability, which revealed socio-cultural behaviors and beliefs. They form a unique, efficient system of hydraulic engineering that demonstrates the region’s traditional understanding of the sustainable use and management of its land, water, and agricultural biodiversity. Ancient water harvesting techniques integrated stepwells into agricultural and irrigation networks using prefabricated structures, to allow open channel flow, networked with surface water bodies. They demonstrated the use of Persian wheels, non-mechanized farm machinery, other agricultural implements, etc., and their structure utilized a vast array of local building materials, including granite, marble, sandstone, bricks, lime, mud, wood, etc. The utilization of agricultural wastes, such as rice husk, in the production of lakhori bricks is strongly associated with circular economy principles. They not only communicated and guided communities regarding water management and cleaner production, but also revealed historic knowledge regarding how ancient societies achieved social-ecological resilience. In addition to that, in almost all types of stepwells, aesthetics and ornamentation played an important role and served as a rich source of history to disseminate knowledge of governance, political ideas, social practices and lifestyle. Just a few studies on these stepwells have been published and they have generally focused on their history or on the construction materials of a specific stepwell, rather than offering a wide perspective. This review article will explore the scientific, architectural, artistic, and functional dimensions of all major stepwells in India that have either disappeared or lost their relevance owing to expanding human population and environmental stress. Additionally, this will provide an opportunity to rethink modern water engineering systems and redesign water infrastructure with less negative environmental impacts to achieve the Sustainable Development Goals and ensure water for all.

Smart Technologies for Water Resource Management: An Overview.

The latest progress in information and communication technology (ICT) and the Internet of Things (IoT) have opened up new opportunities for real-time monitoring and controlling of cities’ structures, infrastructures, and services. In this context, smart water management technology provides the data and tools to help users more effectively manage water usage. Data collected with smart water devices are being integrated with building management systems to show how much water is used by occupants as well as to identify the consumption areas to use water more efficiently. By this approach, smart buildings represent an innovative solution that enhances a city’s sustainability and contributes to overcoming environmental challenges due to increasing population and climate change. One of the main challenges is resource-saving and recovery. Water is an all-important need of all living beings, and the concerns of its scarcity impose a transition to innovative and sustainable management starting from the building scale. Thus, this manuscript aims to provide an updated and valuable overview for researchers, consumers, and stakeholders regarding implementing smart and sustainable technologies for water resource management, primarily for building-scale uses.

Automated real-time irrigation analytics inform diversity in regional irrigator behavior and water withdrawal and use characteristics

Effective agricultural water management requires accurate, continuous, and transparent accounting of water use in irrigated agroecosystems, especially in water-limited regions where moratoriums may be imposed. Advances in sensor technologies, networking, and data analytics can aid in fulfilling this task by automatically collecting, analyzing and reporting real-time data to infer irrigators’ practices and behaviors, crop water requirements, water applications and use. In this research, an automated irrigation water withdrawal and water use monitoring and data collection system was deployed to monitor actual irrigation dynamics for 31 commercial and large-scale agricultural production fields for three consecutive years. Production scale fields (representing a total of 1050 ha) included center pivot (P), gravity (surface/furrow) (G) and subsurface drip-irrigated (S) fields. On average, irrigation was initiated 40–70 days after planting (DAP) and terminated by 120–140 DAP. The proportion of irrigation systems operating simultaneously and peak water abstraction were highest (70–90 %) during July and August. Mean depth of water applied across all fields was 243, 264 and 284 mm in 2013, 2014 and 2015, respectively. Site-specific monitoring of precipitation, soil moisture, and evaporative demand and a soil-water balance model resulted in mean seasonal irrigation requirement estimates of 394, 242 and 184 mm, in 2013, 2014 and 2015, respectively; for maize; and 307, 163 and 219 mm in 2013, 2014 and 2015, respectively, for soybean. Despite reduction of calculated mean irrigation requirement in 2014 and 2015 by 40–50 %, actual irrigation applications by producers did not change considerably and irrigation applied exceeded irrigation water requirements in 80 % of the fields, suggesting needs for irrigation water management technology implementation and associated educational programs in the region. Some fields showed irrigation applications exceeding the mean annual allocated (moratorium) irrigation depth (305 mm), implying that irrigation decisions are still largely driven by non-scientific and/or technical methods. While substantial farm-to-farm heterogeneity makes it challenging to robustly benchmarking regional water footprint and irrigator behavior, it also creates an opportunity for developing and implementing methodologies and strategies for real-time monitoring of farm-level irrigation dynamics. New advances in technologies with telemetry capabilities as well as internet of things (IoTs) can be leveraged to effectively create databases, track and compare water usage to better plan, allocate, distribute, monitor and manage limited water resources for enhancing agricultural productivity. These processes can also be used for education and demonstration for irrigation professionals to enhance adoption of such technologies. This research has the potential for technology and strategy transfer for advanced water management to other regions in the United States and globally.

Thirty years of water management research for rice in sub-Saharan Africa: Achievement and perspectives

Rice is one of the major staple foods in sub-Saharan Africa (SSA) and is mainly grown in three environments: rainfed upland and rainfed and irrigated lowlands. In all rice-growing environments, the yield gap (the difference between the potential yield in irrigated lowland or water-limited yield in rainfed lowland and upland and the actual yield obtained by farmers) is largely due to a wide range of constraints including water-related issues. This paper aims to review water management research for rice cultivation in SSA. Major water-related constraints to rice production include drought, flooding, iron toxicity, and soil salinity. A wide range of technologies has been tested by Africa Rice Center (AfricaRice) and its partners for their potential to address some of the water-related challenges across SSA. In the irrigated lowlands, the system of rice intensification and alternate wetting and drying significantly reduced water use, while the pre-conditions to maintain grain yield and quality compared to continuous flooding were identified. Salinity problems caused by the standing water layer could be addressed by flushing and leaching. In the rainfed lowlands, water control structures, Sawah rice production system, and the Smart-Valleys approach for land and water development improved water availability and grain yield compared to traditional water management practices. In the rainfed uplands, supplemental irrigation, mulching, and conservation agriculture mitigated the effects of drought on rice yield. The Participatory Learning and Action Research (PLAR) approach was developed to work with and educate communities to help them implement improved water management technologies. Most of the research assessed a few indicators such as rice yield, water use, water productivity at the field level. There has been limited research on the cost-benefit of water management technologies, enabling conditions and business models for their large-scale adoption, as well as their impact on farmers’ livelihoods, particularly on women and youth. Besides, limited research has been conducted on water management design for crop diversification, landscape-level water management, and iron toxicity mitigation, particularly in lowlands. Filling these research gaps could contribute to sustainable water resources management and sustainable intensification of rice-based systems in SSA. • Research on water management for rice cultivation in sub-Saharan Africa was reviewed. • The majority of studies aimed at improving water control in rainfed lowlands. • The studies focused mostly on improving rice yield and water productivity. • Less attention was given to cost-benefits and impact of water control technologies. • Water management was mostly studied at the field- rather than at landscape-level.

Steerable drops on heated concentric microgroove arrays

Guided drop transport is of great importance in various water and thermal management technologies. Unidirectional drop transport on a hot surface has been widely developed, but a bidirectional reversal is still challenging. Here, we report a steerable transport of drop impinging on heated concentric microgroove arrays, on which the directionality of drop transport is dictated by the drop boiling modes. In the transition boiling state, the driving force originated from the Laplace pressure difference rendered by the microgrooves, which enables the drop rebounding towards the center of curvature. While in the film boiling state, a net force towards the opposite side is generated between the grooves and the penetrated liquid, that drives the drop far away from the center of curvature. Our experimental and theoretical results uncover that the lateral displacement is controlled by both the Weber number and off-center distance. These findings strengthen our fundamental understanding of drop impact dynamics at high temperatures and are essential for effective cooling of hot-spot cores and drop sieving.

Assessment of potential for adoption of wireless sensor network technology for irrigation water management of high value crops in the Philippines

This study assessed the potential for adoption of wireless sensor technology (WSN) technology for irrigation water management of high value crops in the Philippines through market survey with farm owners and farm managers as respondents. Surveys were conducted in various regions in the country using non-random sampling methods. The survey basically includes questions about farm information, problems related to water management, familiarity with WSN, and willingness to adopt, among others. Based on the results, 83% of the respondents expressed willingness to adopt the WSN technology if properly demonstrated and if it will give a high return on investment. On the other hand, 76% of the respondents are willing to adopt WSN regardless of the costs provided there is a high return on investment. However, only a little more than half of the respondents are willing to adopt the WSN technology for the sake of modernization. Results also showed a strong potential for adoption of WSN technology using locally-developed sensors with 81% of the respondents providing affirmative answers. Chi-square test results indicated that sex, gross annual household income, membership to farmer’s association, land tenure status, and familiarity with WSN technology are the primary determinants of the potential for adoption regardless of the conditions imposed. However, educational attainment also played a role in the adoption of WSN technology if the purpose is agricultural modernization and if there is a higher return on investment despite some budgetary allocation for the initial costs. Results of this study could serve as a basis for developing commercialization schemes, strategies for upscaling and for agricultural policy formulation.

Optimizing Shade Cultivation Method and Irrigation Amount to Improve Photosynthetic Characteristics, Bean Yield, and Quality of Coffee in a Subtropical Monsoon Climate.

Reasonable water and light management technology can improve economic benefits, coffee yield, and quality. We used cluster analysis and principal component analysis to evaluate and optimize the water and light management technology with high coffee yield, quality, and economic benefits in a subtropical monsoon climate region of China. The experiment was arranged in a randomized complete block design with two factors (3 irrigation levels × 4 shade cultivation treatments) replicated four times during 2016–2017. The irrigation levels consisted of full irrigation (FI) and two deficit irrigations (DIL: 75% FI, DIS: 50% FI). The shade cultivation treatments consisted of no shade cultivation (S0) and three shade cultivation modes (SL: intercropping with four lines of coffee and one line of banana; SM: intercropping with three lines of coffee and one line of banana; SS: intercropping with two lines of coffee and one line of banana). The results showed that the effects of irrigation level and shade cultivation mode on growth, crop yield, most of the photosynthetic characteristics, and nutritional quality were significant (p < 0.05). Regression analysis showed that the leaf radiation use efficiency (RUE) showed a significant negative exponential relation or logistic-curve variation with photosynthetically active radiation (PAR). The bean yield increased with an increase of the shade degree when water was seriously deficient, whereas it first increased and then decreased with an increase of the shade degree under FI and DIL. Based on both cluster analysis and principal component analysis, the FISS treatment resulted in the highest comprehensive quality of coffee, followed by the FISM treatment; the DISS0 treatment obtained the lowest quality. Compared with the FIS0 treatment, the FISM treatment increased the 2-year average bean yield and net income by 15.0 and 28.5%, respectively, whereas the FISS treatment decreased these by 17.8 and 8.7%, respectively. To summarize, FISS treatment significantly improved the nutritional quality of coffee, and FISM treatment significantly increased the dry bean yield and economic benefits of coffee. The results of the study could provide a theoretical basis for water-saving irrigation and shade cultivation management of coffee in a subtropical monsoon climate region of China.

Water–Energy–Carbon Nexus Analysis for Water Supply Systems with Brackish Groundwater Sources in Arid Regions

Limited knowledge on the water–energy–carbon nexus of water supply systems (WSSs) with brackish groundwater sources in arid regions exists to date. In addition, the large amount of fossil-fuel energy utilized by treatment processes generating a significant amount of carbon emissions remains a challenge for the municipalities in Saudi Arabia to meet long-term sustainability goals. To achieve Saudi Arabia Vision 2030’s target of sustainable cities with reduced CO2 emissions, the present study aimed to analyse the water–energy–carbon nexus for WSSs and propose mitigation measures for reducing energy and carbon footprints from both the water management and treatment technologies perspectives. The detailed energy consumption data for three main components (source extraction, water treatment, and conveyance and distribution) of the main WSS, serving the 600,000 population of Buraydah City (Qassim, Saudi Arabia), was obtained from the concerned municipality. The city water treatment plant removes naturally occurring iron, TDS, and radionuclides in the source water with the help of ion detention, oxidation, sand filtration, ultrafiltration, reverse osmosis, chlorination, and backwash water management. The study found that the treatment facility consumes around half of the total system’s energy (131,122 kWh/day); while, with deep confined aquifer (&gt;600 m) and an average water loss of 8%, conveyance and distribution (34%) and source extraction (18%) are consistent with the reported literature. With oil-driven energy, carbon emissions were found to be 10.26, 27.18, and 19.72 million tons CO2 eq/year for source extraction, water treatment, and conveyance and distribution, respectively. The reverse osmosis process, with higher energy consumption—1.1 kWh/m3 of treated water—than the global average, consumes most (88%) of the treatment plant’s energy and thus needs effective energy management practices. Moving to renewable (solar and wind-driven) sources, subject to a detailed life cycle analysis, can achieve significant energy and associated carbon emission reductions. To sustainably meet the water demand of the growing population in arid regions, the study also suggests raising the awareness of the public about how water conservation can control CO2 emissions, proactive maintenance of aging infrastructure, and increasing rainwater and treated wastewater reuse, to enhance the operational life of existing treatment facilities.

Impact of climate change on the agriculture sector and its adaptation strategies

Climate change in Indonesia, including erratic rainfall intensity, extreme temperatures, El Nino and La Nina events, can cause farmers not to implement agricultural efforts optimally. Multiplier effect caused is the risk of decreased agricultural production and even crop failure that causes losses for farmers. The impact can broadly reduce farmers’ welfare, food security and increase poverty, for which most Indonesians livelihood as farmers. The negative consequences of climate change require efforts to minimize the impact and anticipate through adaptation strategies. These research aims are to analyze the impact of climate change on the agriculture sector and develop an adaptation strategy to address the impact of climate change on the agricultural sector. This method uses review literature related to the impact of climate change on agricultural products and adaptation strategies to climate change in the agricultural sector. The impact of climate change caused a decline in agricultural production and even crop failure. The main actors of climate change that affect the agricultural sector include rain patterns, extreme climate events (floods and droughts), and increased air temperatures. Recommendations for adaptation strategies are using superior plants, adjusting planting time and pattern, water management technology (rain harvesting and irrigation), and biotic environmental strategies.

Low Cost System Based on Infrared Technology for Water Management

Abstract Water is an essential element in the life of the human being for which its conservation and good use is necessary, in this work we make a proposal for the development of a low-cost system for water management in order to save on Its consumption, using infrared technology, the results provide a mechanism that can be replicated and at different scales, by the use of commonly used devices.

Polymer/Graphene Nanocomposite Membranes: Status and Emerging Prospects

Graphene is a unique nanocarbon nanomaterial, frequently explored with polymeric matrices for technical purposes. An indispensable application of polymer/graphene nanocomposites has been observed for membrane technology. This review highlights the design, properties, and promising features of the polymer/graphene nanomaterials and nanocomposite membranes for the pervasion and purification of toxins, pollutants, microbials, and other desired contents. The morphology, pore size, pore structure, water flux, permeation, salt rejection, and other membrane properties are examined. Graphene oxide, an important modified form of graphene, is also utilized in nanocomposite membranes. Moreover, polymer/graphene nanofibers are employed to develop high-performance membranes for methodological purposes. The adaptability of polymer/graphene nanocomposites is observed for water management and purification technologies.

Land and water conservation technologies for building carbon positive villages in India

AbstractContinuous and unabated land degradation in India is a threat to agricultural sustainability while increasing temperatures, changing rainfall patterns and precipitation intensification are going to further aggravate degradation in future. The timely adoption of integrated land and water conservation technologies minimises erosion and provides significant adaptation and mitigation co‐benefits. The objectives of this study were to assess the mitigation potential of soil and water conservation technologies and also the feasibility of making villages carbon positive. The extent of minimisation of soil loss due to soil conservation technologies ranges from 0.10 to 21.65 Mg ha−1 yr−1, while carbon emissions minimised range from 0.73 to 158.77 kg ha−1 yr−1. Emission minimisation from various water management technologies in rice ranges from 73.0 to 507.9 kg CO2equivalents ha−1 yr−1. Agroforestry practices can sequester 8.64 to 52.77 Mg CO2ha−1 yr−1besides enhancing system productivity, arresting soil erosion and carbon loss through erosion. Integration of multiple technologies in a farming system further enhances the adaptation and mitigation benefits. Adoption of conservation technologies resulted in a net carbon balance of 0.05–1.23 CO2Mg ha−1 yr−1in 9 villages in India, indicating net positive carbon balance due to reduction of greenhouse gas emissions and carbon sequestration. Building carbon positive villages is a potential approach for preventing land degradation, while enhancing productivity, mitigating climate change and realising the sustainable development goals. Building capacities of communities and establishing institutions in villages are essential for upscaling and maintaining of soil and water conservation structures and community assets in the village. Furthermore, prioritisation and scaling of location specific land and water conservation technologies hold the key to establish carbon‐positive villages.