Assessment of water quality from water harvesting using small farm reservoir for irrigation

NASA Astrophysics Data System (ADS)

Dewi, W. S.; Komariah; Samsuri, I. Y.; Senge, M.

2018-03-01

This study aims to assess the quality of rainfall-runoff water harvesting using small farm reservoir (SFR) for irrigation. Water quality assessment criteria based on RI Government Regulation number 82 the year 2001 on Water Quality Management and Pollution Control, and FAO Irrigation Water Quality Guidelines 1985. The experiment was conducted in the dry land of Wonosari Village, Gondangrejo District, Karanganyar Regency. SFR size was 10 m x 3 m x 2 m. Water quality measurements are done every week, ten times. Water samples were taken at 6 points, namely: distance of 2.5 m, 5 m, and 7.5 m from the inlet, at depth 25 cm and 175 cm from surface water. In each sampling point replicated three times. Water quality parameters include dissolved oxygen (DO), Turbidity (TSS), water pH, Nitrate (NO3), and Phosphate. The results show that water harvesting that collected in SFR meets both standards quality used, so the water is feasible for agricultural irrigation. The average value of harvested water was DO 2.6 mg/l, TSS 62.7 mg/l, pH 6.6, P 5.3 mg/l and NO3 0.16 mg/l. Rainfall-runoff water harvesting using SFR prospectus for increasing save water availability for irrigation.

Flared natural gas-based onsite atmospheric water harvesting (AWH) for oilfield operations

NASA Astrophysics Data System (ADS)

Wikramanayake, Enakshi D.; Bahadur, Vaibhav

2016-03-01

Natural gas worth tens of billions of dollars is flared annually, which leads to resource waste and environmental issues. This work introduces and analyzes a novel concept for flared gas utilization, wherein the gas that would have been flared is instead used to condense atmospheric moisture. Natural gas, which is currently being flared, can alternatively power refrigeration systems to generate the cooling capacity for large scale atmospheric water harvesting (AWH). This approach solves two pressing issues faced by the oil-gas industry, namely gas flaring, and sourcing water for oilfield operations like hydraulic fracturing, drilling and water flooding. Multiple technical pathways to harvest atmospheric moisture by using the energy of natural gas are analyzed. A modeling framework is developed to quantify the dependence of water harvest rates on flared gas volumes and ambient weather. Flaring patterns in the Eagle Ford Shale in Texas and the Bakken Shale in North Dakota are analyzed to quantify the benefits of AWH. Overall, the gas currently flared annually in Texas and North Dakota can harvest enough water to meet 11% and 65% of the water consumption in the Eagle Ford and the Bakken, respectively. Daily harvests of upto 30 000 and 18 000 gallons water can be achieved using the gas currently flared per well in Texas and North Dakota, respectively. In fifty Bakken sites, the water required for fracturing or drilling a new well can be met via onsite flared gas-based AWH in only 3 weeks, and 3 days, respectively. The benefits of this concept are quantified for the Eagle Ford and Bakken Shales. Assessments of the global potential of this concept are presented using data from countries with high flaring activity. It is seen that this waste-to-value conversion concept offers significant economic benefits while addressing critical environmental issues pertaining to oil-gas production.

Rainwater harvesting potentials for drought mitigation in Iran.

PubMed

Tabatabaee, J; Han, M Y

2010-01-01

In order to evaluate the potential of rainwater harvesting (RWH) for mitigating water scarcity in a semi-arid zone of the country (Mashhad-Iran), three typical RWH systems were installed and monitored. The first system consists of 5,000 m² natural ground catchment which was leveled and covered with plastic sheets allowing for maximum possible runoff generation. Surface runoff was conducted into a 500 m³ ground reservoir via a series of draining ditches and an end collection channel. The water collected from a plastic covered catchment was used for irrigation of dryland wheat cultivation. According to the result of two years measurements, grain yield was almost doubled in irrigated plots when compared to conventional rainfed cultivation. In the second RWH system, runoff generated from about 2 ha asphaltic road and parking was diverted into a 1,200 m³ ground reservoir. The results of 2 years measurement for reservoir inflow and outflow indicated that runoff generated during rainy season was sufficient to produce necessary water for irrigating 900 planted fruit trees during successive dry seasons. The last experiment reported here is about a 40 m² roof area which was connected to a plastic tank for runoff measurement. The conclusion was that the proposed RWH system can produce enough water for building's toilets' flashes and other sanitary purposes so that the potable water could be saved considerably. In general, the results of three rainwater harvesting experiments showed the importance of using rainwater for compensating the effect of water shortages which is repeatedly occurring due to the effect of current climate change and ever increasing water utilization for drinking and food production.

A GIS-based approach for identifying potential runoff harvesting sites in the Thukela River basin, South Africa

NASA Astrophysics Data System (ADS)

de Winnaar, G.; Jewitt, G. P. W.; Horan, M.

Water scarce countries such as South Africa are subject to various hydrological constraints which can often be attributed to poor rainfall partitioning, particularly within resource poor farming communities that are reliant on rainfed agriculture. Recent initiatives to address this have shifted focus to explore more efficient alternatives to water supply and the recognition of numerous opportunities to implement runoff harvesting as a means to supplement water availability. However, increasing the implementation of runoff harvesting, without encountering unintended impacts on downstream hydrological and ecological systems, requires better understanding of the hydrologic and environmental impacts at catchment scale. In this paper the representation of spatial variations in landscape characteristics such as soil, land use, rainfall and slope information is shown to be an important step in identifying potential runoff harvesting sites, after which modelling the hydrological response in catchments where extensive runoff harvesting is being considered can be performed and likely impacts assessed. Geographic information systems (GIS) was utilised as an integrating tool to store, analyse and manage spatial information and when linked to hydrological response models, provided a rational means to facilitate decision making by providing catchment level identification, planning and assessment of runoff harvesting sites as illustrated by a case study at the Potshini catchment, a small sub-catchment in the Thukela River basin, South Africa. Through the linked GIS, potential runoff harvesting sites are identified relative to areas that concentrate runoff and where the stored water will be appropriately distributed. Based on GIS analysis it was found that 17% percent of the Potshini catchment area has a high potential for generating surface runoff, whereas an analysis of all factors which influence the location of such systems, shows that 18% is highly suitable for runoff

Highly transparent triboelectric nanogenerator for harvesting water-related energy reinforced by antireflection coating

NASA Astrophysics Data System (ADS)

Liang, Qijie; Yan, Xiaoqin; Gu, Yousong; Zhang, Kui; Liang, Mengyuan; Lu, Shengnan; Zheng, Xin; Zhang, Yue

2015-03-01

Water-related energy is an inexhaustible and renewable energy resource in our environment, which has huge amount of energy and is not largely dictated by daytime and sunlight. The transparent characteristic plays a key role in practical applications for some devices designed for harvesting water-related energy. In this paper, a highly transparent triboelectric nanogenerator (T-TENG) was designed to harvest the electrostatic energy from flowing water. The instantaneous output power density of the T-TENG is 11.56 mW/m2. Moreover, with the PTFE film acting as an antireflection coating, the maximum transmittance of the fabricated T-TENG is 87.4%, which is larger than that of individual glass substrate. The T-TENG can be integrated with silicon-based solar cell, building glass and car glass, which demonstrates its potential applications for harvesting waste water energy in our living environment and on smart home system and smart car system.

Highly transparent triboelectric nanogenerator for harvesting water-related energy reinforced by antireflection coating.

PubMed

Liang, Qijie; Yan, Xiaoqin; Gu, Yousong; Zhang, Kui; Liang, Mengyuan; Lu, Shengnan; Zheng, Xin; Zhang, Yue

2015-03-13

Water-related energy is an inexhaustible and renewable energy resource in our environment, which has huge amount of energy and is not largely dictated by daytime and sunlight. The transparent characteristic plays a key role in practical applications for some devices designed for harvesting water-related energy. In this paper, a highly transparent triboelectric nanogenerator (T-TENG) was designed to harvest the electrostatic energy from flowing water. The instantaneous output power density of the T-TENG is 11.56 mW/m(2). Moreover, with the PTFE film acting as an antireflection coating, the maximum transmittance of the fabricated T-TENG is 87.4%, which is larger than that of individual glass substrate. The T-TENG can be integrated with silicon-based solar cell, building glass and car glass, which demonstrates its potential applications for harvesting waste water energy in our living environment and on smart home system and smart car system.

Nitrogen extraction potential of wild and cultured bivalves harvested from nearshore waters of Cape Cod, USA.

PubMed

Reitsma, Joshua; Murphy, Diane C; Archer, Abigail F; York, Richard H

2017-03-15

As nitrogen entering coastal waters continues to be an issue, much attention has been generated to identify potential options that may help alleviate this stressor to estuaries, including the propagation of bivalves to remove excess nitrogen. Oysters (Crassostrea virginica) and quahogs (Mercenaria mercenaria) from numerous Cape Cod, MA, (USA) sources were analyzed for nitrogen content stored in tissues that would represent a net removal of nitrogen from a water body if harvested. Results showed local oysters average 0.69% nitrogen by total dry weight (mean 0.28gN/animal) and quahogs average 0.67% nitrogen by total dry weight (mean 0.22gN/animal); however, these values did vary by season and to a lesser extent by location or grow-out method. The differences in nitrogen content were largely related to the mass of shell or soft tissue. Nitrogen isotope data indicate shellfish from certain water bodies in the region are incorporating significant amounts of nitrogen from anthropogenic sources. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Exploring Fog Water Harvesting Potential and Quality in the Asir Region, Kingdom of Saudi Arabia

NASA Astrophysics Data System (ADS)

Gandhidasan, P.; Abualhamayel, H. I.

2012-05-01

During the last decade, the exploitation of the existing water resources in the Asir region of the Kingdom of Saudi Arabia has considerably increased due to both the decrease in annual precipitation and the added population pressures from the growing tourist industry. To face the conventional water shortage, attention has been mainly focused on desalination of water. To save the region from severe water shortage, additional new water sources that are low-cost and renewable must be identified. There exists an alternative source of water such as fog water harvesting. Fog forms in the Asir Region more frequently between December and February compared to the other months of the year. This paper presents the study of the climatic conditions in the Asir region of the Kingdom to identify the most suitable location for fog water collection as well as design and testing of two large fog collectors (LFCs) of size 40 m2 along with standard fog collectors (SFCs) of 1 m2 in that region. During the period from 27 December 2009 to 9 March 2010, a total of 3,128.4 and 2,562.4 L of fog water were collected by the LFC at two sites in the Al-Sooda area of the Asir region, near Abha. Experimental results indicate that fog water collection can be combined with rain water harvesting systems to increase water yield during the rainy season. The quality of the collected fog water was analyzed and compared to the World Health Organization (WHO) drinking water standards and found to be potable. An economic analysis was carried out for the proposed method of obtaining fresh water from the fog. The study suggests a clear tendency that in terms of both quality and magnitude of yield, fog is a viable source of water and can be successfully used to supplement water supplies in the Asir region of the Kingdom.

Establishment of sustainable water supply system in small islands through rainwater harvesting (RWH): case study of Guja-do.

PubMed

Han, Mooyoung; Ki, Jaehong

2010-01-01

Many islands in Korea have problems related to water source security and supply. In particular, the water supply condition is worse in small islands which are remote from the mainland. A couple of alternatives are developed and suggested to supply water to islands including water hauling, groundwater extraction, and desalination. However, these alternatives require much energy, cost, and concern in installation and operation. Rainwater harvesting is a sustainable option that supplies water with low energy and cost. However, lack of practical or comprehensive studies on rainwater harvesting systems in these regions hinders the promotion of the system. Therefore, this research examines defects of current RWH systems on an existing island, Guja-do, and provides technical suggestions in quantitative and qualitative aspects. A simple system design modification and expansion of system capacity using empty space such as a wharf structure can satisfy both the qualitative and the quantitative water demand of the island. Since rainwater harvesting is estimated to be a feasible water supply option under the Korean climate, which is an unfavorable condition for rainwater harvesting, implies a high potential applicability of rainwater harvesting technology to other regions over the world suffering from water shortage.

The water factor in harvest-sprouting of hard red spring wheat

NASA Technical Reports Server (NTRS)

Bauer, A.; Black, A. L. (Principal Investigator)

1983-01-01

Sprouting in unthreshed, ripe, hard red spring wheat (Triticum aestivum L.) is induced by rain, but sprouting does not necessarily occur because the crop is wetted. The spike and grain water conditions conducive to sprouting were determined in a series of laboratory experiments. Sprouting did not occur in field growing wheat wetted to 110% water concentration until the spike water concentration was reduced to 12% and maintained at this concentration for 2 days before wetting. When cut at growth stage 11.3, Feekes scale, Saratovskaya 20 (USSR) sprouted after 4 days drying, Olaf and Alex between 7 and 15 days drying and Columbus, recognized for its resistance to harvest time sprouting, after more than 15 days drying. Sprouting potential was enhanced after 4 wetting drying cycles in which any wetted interval was too brief to permit sufficient water imbibition to initiate sprouting. At harvest ripeness, grain water concentration exceeded spike water concentration by 0.7 percentage units. Following 6 months storage, 20% of the kernels in 300 spike bundles (simulating windrows) sprouted within 28 hrs after initiation of wetting to saturation (150% water concentration). Ninety percent sprouting occurred within 8 days in bundles maintained at 75% water concentration and higher, but less sprouting occurred in bundles dried to 50% water concentration before resaturation.

Magnetic-Nanoflocculant-Assisted Water-Nonpolar Solvent Interface Sieve for Microalgae Harvesting.

PubMed

Lee, Kyubock; Na, Jeong-Geol; Seo, Jung Yoon; Shim, Tae Soup; Kim, Bohwa; Praveenkumar, Ramasamy; Park, Ji-Yeon; Oh, You-Kwan; Jeon, Sang Goo

2015-08-26

Exploitation of magnetic flocculants is regarded as a very promising energy-saving approach to microalgae harvesting. However, its practical applicability remains limited, mainly because of the problem of the postharvest separation of magnetic flocculants from microalgal flocs, which is crucial both for magnetic-flocculant recycling and high-purity microalgal biomasses, but which is also a very challenging and energy-consuming step. In the present study, we designed magnetic nanoflocculants dually functionalizable by two different organosilane compounds, (3-aminopropyl)triethoxysilane (APTES) and octyltriethoxysilane (OTES), which flocculate negatively charged microalgae and are readily detachable at the water-nonpolar organic solvent (NOS) interface only by application of an external magnetic field. APTES functionalization imparts a positive zeta potential charge (29.6 mV) to magnetic nanoflocculants, thereby enabling microalgae flocculation with 98.5% harvesting efficiency (with a dosage of 1.6 g of dMNF/g of cells). OTES functionalization imparts lipophilicity to magnetic nanoflocculants to make them compatible with NOS, thus effecting efficient separation of magnetic flocculants passing through the water-NOS interface sieve from hydrophilic microalgae. Our new energy-saving approach to microalgae harvesting concentrates microalgal cultures (∼1.5 g/L) up to 60 g/L, which can be directly connected to the following process of NOS-assisted wet lipid extraction or biodiesel production, and therefore provides, by simplifying multiple downstream processes, a great potential cost reduction in microalgae-based biorefinement.

EU mitigation potential of harvested wood products.

PubMed

Pilli, Roberto; Fiorese, Giulia; Grassi, Giacomo

2015-12-01

The new rules for the Land Use, Land Use Change and Forestry sector under the Kyoto Protocol recognized the importance of Harvested Wood Products (HWP) in climate change mitigation. We used the Tier 2 method proposed in the 2013 IPCC KP Supplement to estimate emissions and removals from HWP from 1990 to 2030 in EU-28 countries with three future harvest scenarios (constant historical average, and +/-20% in 2030). For the historical period (2000-2012) our results are consistent with other studies, indicating a HWP sink equal on average to -44.0 Mt CO 2 yr -1 (about 10% of the sink by forest pools). Assuming a constant historical harvest scenario and future distribution of the total harvest among each commodity, the HWP sink decreases to -22.9 Mt CO 2 yr -1 in 2030. The increasing and decreasing harvest scenarios produced a HWP sink of -43.2 and -9.0 Mt CO 2 yr -1 in 2030, respectively. Other factors may play an important role on HWP sink, including: (i) the relative share of different wood products, and (ii) the combined effect of production, import and export on the domestic production of each commodity. Maintaining a constant historical harvest, the HWP sink will slowly tend to saturate, i.e. to approach zero in the long term. The current HWP sink will be maintained only by further increasing the current harvest; however, this will tend to reduce the current sink in forest biomass, at least in the short term. Overall, our results suggest that: (i) there is limited potential for additional HWP sink in the EU; (ii) the HWP mitigation potential should be analyzed in conjunction with other mitigation components (e.g. sink in forest biomass, energy and material substitution by wood).

Harvesting Water from Air: Using Anhydrous Salt with Sunlight.

PubMed

Li, Renyuan; Shi, Yusuf; Shi, Le; Alsaedi, Mossab; Wang, Peng

2018-05-01

Atmospheric water is an abundant alternative water resource, equivalent to 6 times the water in all rivers on Earth. This work screens 14 common anhydrous and hydrated salt couples in terms of their physical and chemical stability, water vapor harvesting, and release capacity under relevant application scenarios. Among the salts screened, copper chloride (CuCl 2 ), copper sulfate (CuSO 4 ), and magnesium sulfate (MgSO 4 ) distinguish themselves and are further made into bilayer water collection devices, with the top layer being the photothermal layer, while the bottom layer acts as a salt-loaded fibrous membrane. The water collection devices are capable of capturing water vapor out of the air with low relative humidity (down to 15%) and releasing water under regular and even weakened sunlight (i.e., 0.7 kW/m 2 ). The work shines light on the potential use of anhydrous salt toward producing drinking water in water scarce regions.

Financial and environmental modelling of water hardness--implications for utilising harvested rainwater in washing machines.

PubMed

Morales-Pinzón, Tito; Lurueña, Rodrigo; Gabarrell, Xavier; Gasol, Carles M; Rieradevall, Joan

2014-02-01

A study was conducted to determine the financial and environmental effects of water quality on rainwater harvesting systems. The potential for replacing tap water used in washing machines with rainwater was studied, and then analysis presented in this paper is valid for applications that include washing machines where tap water hardness may be important. A wide range of weather conditions, such as rainfall (284-1,794 mm/year); water hardness (14-315 mg/L CaCO3); tap water prices (0.85-2.65 Euros/m(3)) in different Spanish urban areas (from individual buildings to whole neighbourhoods); and other scenarios (including materials and water storage capacity) were analysed. Rainfall was essential for rainwater harvesting, but the tap water prices and the water hardness were the main factors for consideration in the financial and the environmental analyses, respectively. The local tap water hardness and prices can cause greater financial and environmental impacts than the type of material used for the water storage tank or the volume of the tank. The use of rainwater as a substitute for hard water in washing machines favours financial analysis. Although tap water hardness significantly affects the financial analysis, the greatest effect was found in the environmental analysis. When hard tap water needed to be replaced, it was found that a water price of 1 Euro/m(3) could render the use of rainwater financially feasible when using large-scale rainwater harvesting systems. When the water hardness was greater than 300 mg/L CaCO3, a financial analysis revealed that an net present value greater than 270 Euros/dwelling could be obtained at the neighbourhood scale, and there could be a reduction in the Global Warming Potential (100 years) ranging between 35 and 101 kg CO2 eq./dwelling/year. Copyright © 2013 Elsevier B.V. All rights reserved.

Applicability of ERTS to Antarctic iceberg resources. [harvesting icebergs for fresh water

NASA Technical Reports Server (NTRS)

Hult, J. L.; Ostrander, N. C.

1974-01-01

This investigation explores the applicability of ERTS to: (1) determine the Antarctic sea ice and environmental behavior that may influence the harvesting of icebergs, and (2) monitor iceberg locations, characteristics, and evolution. Imagery sampling in the western Antarctic between the Peninsula and the Ross Sea is used in the analysis. It is found that the potential applicability of ERTS to the research, planning, and harvesting operations can contribute importantly to the glowing promise derived from broader scope studies for the use of Antarctic icebergs to relieve a growing global thirst for fresh water. Several years of comprehensive monitoring will be necessary to characterize sea-ice and environmental behavior and iceberg evolution. Live ERTS services will assist harvesting control and claiming operations and offer a means for harmonizing entitlements to iceberg resources.

Water flow energy harvesters for autonomous flowmeters

NASA Astrophysics Data System (ADS)

Boisseau, Sebastien; Duret, Alexandre-Benoit; Perez, Matthias; Jallas, Emmanuel; Jallas, Eric

2016-11-01

This paper reports on a water flow energy harvester exploiting a horizontal axis turbine with distributed magnets of alternate polarities at the rotor periphery and air coils outside the pipe. The energy harvester operates down to 1.2L/min with an inlet section of 20mm of diameter and up to 25.2mW are provided at 20L/min in a 2.4V NiMH battery through a BQ25504 power management circuit. The pressure loss induced by the insertion of the energy harvester in the hydraulic circuit and by the extraction of energy has been limited to 0.05bars at 30L/min, corresponding to a minor loss coefficient of KEH=3.94.

Ground-water response to forest harvest: implications for hillslope stability

Treesearch

A.C. Johnson; R.T. Edwards; R. Erhardt

2007-01-01

Timber harvest may contribute to increased landsliding frequency through increased soil saturation or loss of soil strength as roots decay. This study assessed the effects of forest harvest on hillslope hydrology and linked hydrologic change before and after harvest with a simple model of hillslope stability. Observations of peak water table heights in 56 groundwater...

Energy Harvesting from Fluid Flow in Water Pipelines for Smart Metering Applications

NASA Astrophysics Data System (ADS)

Hoffmann, D.; Willmann, A.; Göpfert, R.; Becker, P.; Folkmer, B.; Manoli, Y.

2013-12-01

In this paper a rotational, radial-flux energy harvester incorporating a three-phase generation principle is presented for converting energy from water flow in domestic water pipelines. The energy harvester together with a power management circuit and energy storage is used to power a smart metering system installed underground making it independent from external power supplies or depleting batteries. The design of the radial-flux energy harvester is adapted to the housing of a conventional mechanical water flow meter enabling the use of standard components such as housing and impeller. The energy harvester is able to generate up to 720 mW when using a flow rate of 20 l/min (fully opened water tab). A minimum flow rate of 3 l/min is required to get the harvester started. In this case a power output of 2 mW is achievable. By further design optimization of the mechanical structure including the impeller and magnetic circuit the threshold flow rate can be further reduced.

Forest harvesting reduces the soil metagenomic potential for biomass decomposition.

PubMed

Cardenas, Erick; Kranabetter, J M; Hope, Graeme; Maas, Kendra R; Hallam, Steven; Mohn, William W

2015-11-01

Soil is the key resource that must be managed to ensure sustainable forest productivity. Soil microbial communities mediate numerous essential ecosystem functions, and recent studies show that forest harvesting alters soil community composition. From a long-term soil productivity study site in a temperate coniferous forest in British Columbia, 21 forest soil shotgun metagenomes were generated, totaling 187 Gb. A method to analyze unassembled metagenome reads from the complex community was optimized and validated. The subsequent metagenome analysis revealed that, 12 years after forest harvesting, there were 16% and 8% reductions in relative abundances of biomass decomposition genes in the organic and mineral soil layers, respectively. Organic and mineral soil layers differed markedly in genetic potential for biomass degradation, with the organic layer having greater potential and being more strongly affected by harvesting. Gene families were disproportionately affected, and we identified 41 gene families consistently affected by harvesting, including families involved in lignin, cellulose, hemicellulose and pectin degradation. The results strongly suggest that harvesting profoundly altered below-ground cycling of carbon and other nutrients at this site, with potentially important consequences for forest regeneration. Thus, it is important to determine whether these changes foreshadow long-term changes in forest productivity or resilience and whether these changes are broadly characteristic of harvested forests.

Applicability of ERTS to Antarctic iceberg resources. [harvesting sea ice for fresh water

NASA Technical Reports Server (NTRS)

Hult, J. L. (Principal Investigator); Ostrander, N. C.

1973-01-01

The author has identified the following significant results. This investigation explorers the applicability of ERTS to (1) determine the Antarctic sea ice and environmental behavior that may influence the harvesting of icebergs, and (2) monitor iceberg locations, characteristics, and evolution. Imagery has shown that the potential applicability of ERTS to the research, planning, and harvesting operations can contribute importantly to the glowing promise derived from broader scope studies for the use of Antarctic icebergs to relieve a growing global thirst for fresh water. Several years of comprehensive monitoring will be necessary to characterize sea ice and environmental behavior and iceberg evolution. Live ERTS services will assist harvesting control and claiming operations and offer a means of harmonizing entitlements of iceberg resources. The valuable ERTS services will be more cost effective than other means will be easily justified and borne by the iceberg harvesting operations.

Economic Evaluation and Overall Assessment of Water Harvesting Ponds based on Scorecard System: A Case Study

NASA Astrophysics Data System (ADS)

Dabral, P. P.; Kumar, Santosh; Kiku, Karmchand

2017-12-01

In the present study, an attempt has been made to carry out an economic analysis of three (03) water harvesting ponds situated in the district of Lakhimpur (Assam), India. Economic analysis was carried out using three important economic criteria, namely Benefit Cost Ratio (BCR), Net Present Worth (NPW) and the Internal Rate of Returns (IRR). Ponds of the study area were compared with adopting score card system. All the water harvesting ponds were found economically viable as the BCR was more than unity at 12% discount rate. Net present worth was the highest for the water harvesting pond of Radhapukheri Fish Seed Farm, Department of Fisheries, Govt. of Assam, Narayanpur and the least for water harvesting pond of St. Xavier's School, Harmoti. The IRR was found to be the highest (60%) for water harvesting ponds of St. Xavier's School, Harmoti followed by water harvesting pond of a farmer of Narayanpur (48%) and water harvesting pond of Radhapukheri Fish Seed Farm (19.2%).Water harvesting pond of Radhapukheri Fish Seed Farm, Narayanpur scored the highest score (84 marks) followed by water harvesting pond of a farmer of Narayanpur (80 marks) and St. Xavier's school, Harmoti (61 marks).

Harvesting broadband kinetic impact energy from mechanical triggering/vibration and water waves.

PubMed

Wen, Xiaonan; Yang, Weiqing; Jing, Qingshen; Wang, Zhong Lin

2014-07-22

We invented a triboelectric nanogenerator (TENG) that is based on a wavy-structured Cu-Kapton-Cu film sandwiched between two flat nanostructured PTFE films for harvesting energy due to mechanical vibration/impacting/compressing using the triboelectrification effect. This structure design allows the TENG to be self-restorable after impact without the use of extra springs and converts direct impact into lateral sliding, which is proved to be a much more efficient friction mode for energy harvesting. The working mechanism has been elaborated using the capacitor model and finite-element simulation. Vibrational energy from 5 to 500 Hz has been harvested, and the generator's resonance frequency was determined to be ∼100 Hz at a broad full width at half-maximum of over 100 Hz, producing an open-circuit voltage of up to 72 V, a short-circuit current of up to 32 μA, and a peak power density of 0.4 W/m(2). Most importantly, the wavy structure of the TENG can be easily packaged for harvesting the impact energy from water waves, clearly establishing the principle for ocean wave energy harvesting. Considering the advantages of TENGs, such as cost-effectiveness, light weight, and easy scalability, this approach might open the possibility for obtaining green and sustainable energy from the ocean using nanostructured materials. Lastly, different ways of agitating water were studied to trigger the packaged TENG. By analyzing the output signals and their corresponding fast Fourier transform spectra, three ways of agitation were evidently distinguished from each other, demonstrating the potential of the TENG for hydrological analysis.

Thermal Harvesting Potential of the Human Body

NASA Astrophysics Data System (ADS)

Thielen, Moritz; Kara, Gökhan; Unkovic, Ivana; Majoe, Dennis; Hierold, Christofer

2018-02-01

Thermoelectric energy harvesting of human body heat might supplement or even replace conventional energy storage in wearable devices for healthcare and the Internet of Humans. Although a number of thermal harvesters are presented in the literature, no conclusive data can be found on the amount of available thermal energy provided by different individuals and activities. We here present the results of an observational study with 56 test subjects of different ages (children, adults and elderly) and gender, performing predefined activities (sitting, walking) in varying environments (indoor, outdoor). Our study showed a statistical difference of thermal potential and skin properties between age groups, but not between genders. On average, stationary elderly test subjects produced ˜ 32% less heat flux compared to minors (mean: children = 13.9 mW/cm2, adults = 11.4 mW/cm2, elderly = 9.4 mW/cm2). This potentially correlates with an increase in thermal skin resistance with age (children = 494 cm2 K/W, adults = 549 cm2 K/W, elderly = 835 cm2 K/W). The mean harvested power varied from 12.2 μW/cm2 (elderly) to 26.2 μW/cm2 (children) for stationary, and from 20.2 μW/cm2 (elderly) to 69.5 μW/cm2 (children) for active subjects inside of a building. The findings of this study can be used to better anticipate the available energy for different usage scenarios of thermal harvesters and optimize wearable systems accordingly.

Thermal Harvesting Potential of the Human Body

NASA Astrophysics Data System (ADS)

Thielen, Moritz; Kara, Gökhan; Unkovic, Ivana; Majoe, Dennis; Hierold, Christofer

2018-06-01

Thermoelectric energy harvesting of human body heat might supplement or even replace conventional energy storage in wearable devices for healthcare and the Internet of Humans. Although a number of thermal harvesters are presented in the literature, no conclusive data can be found on the amount of available thermal energy provided by different individuals and activities. We here present the results of an observational study with 56 test subjects of different ages (children, adults and elderly) and gender, performing predefined activities (sitting, walking) in varying environments (indoor, outdoor). Our study showed a statistical difference of thermal potential and skin properties between age groups, but not between genders. On average, stationary elderly test subjects produced ˜ 32% less heat flux compared to minors (mean: children = 13.9 mW/cm2, adults = 11.4 mW/cm2, elderly = 9.4 mW/cm2). This potentially correlates with an increase in thermal skin resistance with age (children = 494 cm2 K/W, adults = 549 cm2 K/W, elderly = 835 cm2 K/W). The mean harvested power varied from 12.2 μW/cm2 (elderly) to 26.2 μW/cm2 (children) for stationary, and from 20.2 μW/cm2 (elderly) to 69.5 μW/cm2 (children) for active subjects inside of a building. The findings of this study can be used to better anticipate the available energy for different usage scenarios of thermal harvesters and optimize wearable systems accordingly.

Assessing the Potential for Rooftop Rainwater Harvesting from Large Public Institutions.

PubMed

Adugna, Dagnachew; Jensen, Marina Bergen; Lemma, Brook; Gebrie, Geremew Sahilu

2018-02-14

As in many other cities, urbanization coupled with population growth worsens the water supply problem of Addis Ababa, Ethiopia, with a water supply deficit of 41% in 2016. To investigate the potential contribution of rooftop rainwater harvesting (RWH) from large public institutions, 320 such institutions were selected and grouped into 11 categories, from which 25-30% representative 588 rooftops were digitalized and the potential RWH volume computed based on a ten-year rainfall dataset. When comparing the resulting RWH potential with the water consumption, up to 2.3% of the annual, potable water supply can be provided. If reused only within one's own institution, the self-sufficiency varies from 0.9 to 649%. Non-uniform rainfall patterns add uncertainty to these numbers, since the size of the storage tank becomes critical for coverage in the dry season from October to May. Despite the low replacement potential at the city level, RWH from large institutions will enable a significant volume of potable water to be transferred to localities critically suffering from water shortage. Further, large institutions may demonstrate how RWH can be practiced, thus acting as a frontrunner for the dissemination of RWH to other types of rooftops. To narrow the water supply gap, considering rooftop RWH as an alternative water supply source is recommended. However, the present study assumed that financial constraints to install large sized storage tanks are considered as a possible challenge. Thus, future research is needed to investigate the cost-benefit balance along with the invention of a cheap storage tank as they may affect the potential contribution of RWH from rooftops.

Potentiality of rainwater harvesting for an urban community in Bangladesh

NASA Astrophysics Data System (ADS)

Akter, Aysha; Ahmed, Shoukat

2015-09-01

Due to cost effectiveness, rainwater harvesting (RWH) systems are practicing already in some rural parts of Bangladesh but very few in urban areas. This paper aimed to evaluate the potentiality of RWH systems in the South Agrabad in Chittagong city with an average annual precipitation of 3000 mm, experiencing both water scarcity and urban flooding in the same year. The adopted approach was Analytic Hierarchy Process (AHP) based multicriteria decision analysis technique, and the evaluation criteria were roof area, slope, drainage density and runoff coefficient. Geospatial Hydrologic Modeling Extension supported hydrologic model viz. HEC-HMS used to simulate the precipitation-runoff process, the model outcomes showed RWH potentiality which could minimize stagnant storm water up to 26% through supplementing city water supply annually up to 20 liter/person/day. Then, assigning suitable weightage to the evaluation criteria with their associated features in ArcGIS 9.3, the study area was reasonably divided into three potential zones i.e. good, moderate and poor covering 19%, 64% and 17% of the total area respectively. Thus, this is envisaged AHP using HEC-HMS could provide important guidance to the decision supporting system not only for urban areas but also for the wide sub-basin/basin context.

Effects of harvesting cypress swamps on water quality and quantity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ewel, K.C.

1985-09-01

The responses of cypress swamps to a spectrum of harvest techniques are being studied in the Withlacoochee State Forest, Hernando County, Florida. Among the 11 swamps in the study area, four contain plots that were harvested experimentally in 1984. Stand improvement cuts were made in plots in two large swamps. Measurements of tree biomass were made in all but two of the large swamps. The swamps were surveyed for cone production in the fall and regeneration in the spring. However, coppice was produced in all the harvested plots. These preliminary results suggest that coppice production may be a dependable regenerationmore » method, although it may not be desirable for stand improvement cuts and thinning. Evapotranspiration from three cypress swamps averaged 79 cm over a 3-year period. The purpose of this project was to determine specific impacts of harvesting on water quality and water loss rates in the study areas.« less

Hydrophilic directional slippery rough surfaces for water harvesting

PubMed Central

Sun, Nan; Nielsen, Steven O.; Wang, Jing

2018-01-01

Multifunctional surfaces that are favorable for both droplet nucleation and removal are highly desirable for water harvesting applications but are rare. Inspired by the unique functions of pitcher plants and rice leaves, we present a hydrophilic directional slippery rough surface (SRS) that is capable of rapidly nucleating and removing water droplets. Our surfaces consist of nanotextured directional microgrooves in which the nanotextures alone are infused with hydrophilic liquid lubricant. We have shown through molecular dynamics simulations that the physical origin of the efficient droplet nucleation is attributed to the hydrophilic surface functional groups, whereas the rapid droplet removal is due to the significantly reduced droplet pinning of the directional surface structures and slippery interface. We have further demonstrated that the SRS, owing to its large surface area, hydrophilic slippery interface, and directional liquid repellency, outperforms conventional liquid-repellent surfaces in water harvesting applications. PMID:29670942

Light-harvesting photocatalysis for water oxidation using mesoporous organosilica.

PubMed

Takeda, Hiroyuki; Ohashi, Masataka; Goto, Yasutomo; Ohsuna, Tetsu; Tani, Takao; Inagaki, Shinji

2014-07-14

An organic-based photocatalysis system for water oxidation, with visible-light harvesting antennae, was constructed using periodic mesoporous organosilica (PMO). PMO containing acridone groups in the framework (Acd-PMO), a visible-light harvesting antenna, was supported with [Ru(II)(bpy)3(2+)] complex (bpy = 2,2'-bipyridyl) coupled with iridium oxide (IrO(x)) particles in the mesochannels as photosensitizer and catalyst, respectively. Acd-PMO absorbed visible light and funneled the light energy into the Ru complex in the mesochannels through excitation energy transfer. The excited state of Ru complex is oxidatively quenched by a sacrificial oxidant (Na2S2O8) to form Ru(3+) species. The Ru(3+) species extracts an electron from IrO(x) to oxidize water for oxygen production. The reaction quantum yield was 0.34 %, which was improved to 0.68 or 1.2 % by the modifications of PMO. A unique sequence of reactions mimicking natural photosystem II, 1) light-harvesting, 2) charge separation, and 3) oxygen generation, were realized for the first time by using the light-harvesting PMO. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Highly Adaptive Solid-Liquid Interfacing Triboelectric Nanogenerator for Harvesting Diverse Water Wave Energy.

PubMed

Zhao, Xue Jiao; Kuang, Shuang Yang; Wang, Zhong Lin; Zhu, Guang

2018-05-22

Harvesting water wave energy presents a significantly practical route to energy supply for self-powered wireless sensing networks. Here we report a networked integrated triboelectric nanogenerator (NI-TENG) as a highly adaptive means of harvesting energy from interfacing interactions with various types of water waves. Having an arrayed networking structure, the NI-TENG can accommodate diverse water wave motions and generate stable electric output regardless of how random the water wave is. Nanoscaled surface morphology consisting of dense nanowire arrays is the key for obtaining high electric output. A NI-TENG having an area of 100 × 70 mm 2 can produce a stable short-circuit current of 13.5 μA and corresponding electric power of 1.03 mW at a water wave height of 12 cm. This merit promises practical applications of the NI-TENG in real circumstances, where water waves are highly variable and unpredictable. After energy storage, the generated electric energy can drive wireless sensing by autonomously transmitting data at a period less than 1 min. This work proposes a viable solution for powering individual standalone nodes in a wireless sensor network. Potential applications include but are not limited to long-term environment monitoring, marine surveillance, and off-shore navigation.

Assessing the biophysical and socio-economic potential of Sustainable Land Management and Water Harvesting Technologies for rainfed agriculture across semi-arid Africa.

NASA Astrophysics Data System (ADS)

Irvine, Brian; Fleskens, Luuk; Kirkby, Mike

2016-04-01

Stakeholders in recent EU projects identified soil erosion as the most frequent driver of land degradation in semi-arid environments. In a number of sites, historic land management and rainfall variability are recognised as contributing to the serious environmental impact. In order to consider the potential of sustainable land management and water harvesting techniques stakeholders and study sites from the projects selected and trialled both local technologies and promising technologies reported from other sites . The combined PESERA and DESMICE modelling approach considered the regional effects of the technologies in combating desertification both in environmental and socio-economical terms. Initial analysis was based on long term average climate data with the model run to equilibrium. Current analysis, primarily based on the WAHARA study sites considers rainfall variability more explicitly in time series mode. The PESERA-DESMICE approach considers the difference between a baseline scenario and a (water harvesting) technology scenario, typically, in terms of productivity, financial viability and scope for reducing erosion risk. A series of 50 year rainfall realisations are generated from observed data to capture a full range of the climatic variability. Each realisation provides a unique time-series of rainfall and through modelling can provide a simulated time-series of crop yield and erosion risk for both baseline conditions and technology scenarios. Subsequent realisations and model simulations add to an envelope of the potential crop yield and cost-benefit relations. The development of such envelopes helps express the agricultural and erosional risk associated with climate variability and the potential for conservation measures to absorb the risk, highlighting the probability of achieving a given crop yield or erosion limit. Information that can directly inform or influence the local adoption of conservation measures under the climatic variability in semi

Climate relationships to fecal bacterial densities in Maryland shellfish harvest waters.

PubMed

Leight, A K; Hood, R; Wood, R; Brohawn, K

2016-02-01

Coastal states of the United States (US) routinely monitor shellfish harvest waters for types of bacteria that indicate the potential presence of fecal pollution. The densities of these indicator bacteria in natural waters may be related to climate in several ways, including through runoff from precipitation and survival related to water temperatures. The relationship between interannual precipitation and air temperature patterns and the densities of fecal indicator bacteria in shellfish harvest waters in Maryland's portion of the Chesapeake Bay was quantified using 34 years of data (1979-2013). Annual and seasonal precipitation totals had a strong positive relationship with average fecal coliform levels (R(2) = 0.69) and the proportion of samples with bacterial densities above the FDA regulatory criteria (R(2) = 0.77). Fecal coliform levels were also significantly and negatively related to average annual air temperature (R(2) = -0.43) and the average air temperature of the warmest month (R(2) = -0.57), while average seasonal air temperature was only significantly related to fecal coliform levels in the summer. River and regional fecal coliform levels displayed a wide range of relationships with precipitation and air temperature patterns, with stronger relationships in rural areas and mainstem Bay stations. Fecal coliform levels tended to be higher in years when the bulk of precipitation occurred throughout the summer and/or fall (August to September). Fecal coliform levels often peaked in late fall and winter, with precipitation peaking in summer and early fall. Continental-scale sea level pressure (SLP) analysis revealed an association between atmospheric patterns that influence both extratropical and tropical storm tracks and very high fecal coliform years, while regional precipitation was found to be significantly correlated with the Atlantic Multidecadal Oscillation and the Pacific North American Pattern. These findings indicate that management of

Silicone-Based Triboelectric Nanogenerator for Water Wave Energy Harvesting.

PubMed

Xiao, Tian Xiao; Jiang, Tao; Zhu, Jian Xiong; Liang, Xi; Xu, Liang; Shao, Jia Jia; Zhang, Chun Lei; Wang, Jie; Wang, Zhong Lin

2018-01-31

Triboelectric nanogenerator (TENG) has been proven to be efficient for harvesting water wave energy, which is one of the most promising renewable energy sources. In this work, a TENG with a silicone rubber/carbon black composite electrode was designed for converting the water wave energy into electricity. The silicone-based electrode with a soft texture provides a better contact with the dielectric film. Furthermore, a spring structure is introduced to transform low-frequency water wave motions into high-frequency vibrations. They together improve the output performance and efficiency of TENG. The output performances of TENGs are further enhanced by optimizing the triboelectric material pair and tribo-surface area. A spring-assisted TENG device with the segmented silicone rubber-based electrode structure was sealed into a waterproof box, which delivers a maximum power density of 2.40 W m -3 , as triggered by the water waves. The present work provides a new strategy for fabricating high-performance TENG devices by coupling flexible electrodes and spring structure for harvesting water wave energy.

Life Cycle Assessment of Domestic and Agricultural Rainwater Harvesting Systems

EPA Science Inventory

To further understanding of the environmental implications of rainwater harvesting and its water savings potential relative to conventional U.S. water delivery infrastructure, we present a method to perform life cycle assessment of domestic rainwater harvesting (DRWH) and agricul...

Harvesting energy from low-frequency excitations through alternate contacts between water and two dielectric materials.

PubMed

Yu, Jian; Ma, Enze; Ma, Tianwei

2017-12-07

Recent studies have demonstrated the benefits of water-dielectric interfaces in electrostatic energy harvesting. Most efforts have been focused on extracting the kinetic energy from the motions of water drops on hydrophobic surfaces, and thus, the resulting schemes inherently prefer cases where the water drops move at a high speed, or vibrate at a high frequency. Here we report a method for directly harvesting ambient mechanical energy as electric potential energy through water droplets by making alternate contacts with CYTOP and PTFE thin films. Because CYTOP and PTFE acquire significantly different surface charge densities during contact with water, such a difference can be utilized to effectively generate electricity. We demonstrate this concept using prototype devices fabricated on silicon substrates with a simple procedure. In the experiments conducted, a water drop of 400 μL alone could generate a peak open-circuit voltage of 42 V under a 0.25 Hz vibration. Under a 2.5 Hz vibration, the peak open-circuit voltage reached 115 V under an external bias of 8 V. The demonstrated efficiency is orders of magnitude higher than those of existing devices of similar dimensions.

Effect of harvesting on forest soil and water in an organic soil watershed

Treesearch

J.M. Grace; R.W. Skaggs

2006-01-01

Timber harvest operations are necessary and common in forest management to provide profitability and satisfy demands for timber products. Harvesting operations, as with most forest operations, have received much attention in regards to soil and water issues. Harvesting operations have been reported to affect soil physical properties and hydrological characteristics...

Assessment of atmospheric moisture harvesting by direct cooling

NASA Astrophysics Data System (ADS)

Gido, Ben; Friedler, Eran; Broday, David M.

2016-12-01

The enormous amount of water vapor present in the atmosphere may serve as a potential water resource. An index is proposed for assessing the feasibility and energy requirements of atmospheric moisture harvesting by a direct cooling process. A climate-based analysis of different locations reveals the global potential of this process. We demonstrate that the Moisture Harvesting Index (MHI) can be used for assessing the energy requirements of atmospheric moisture harvesting. The efficiency of atmospheric moisture harvesting is highly weather and climate dependent, with the smallest estimated energy requirement found at the tropical regions of the Philippines (0.23 kW/L). Less favorable locations have much higher energy demands for the operation of an atmospheric moisture harvesting device. In such locations, using the MHI to select the optimal operation time periods (during the day and the year) can reduce the specific energy requirements of the process dramatically. Still, using current technology the energy requirement of atmospheric moisture harvesting by a direct air cooling process is significantly higher than of desalination by reverse osmosis.

Design guidelines of triboelectric nanogenerator for water wave energy harvesters.

PubMed

Ahmed, Abdelsalam; Hassan, Islam; Jiang, Tao; Youssef, Khalid; Liu, Lian; Hedaya, Mohammad; Yazid, Taher Abu; Zu, Jean; Wang, Zhong Lin

2017-05-05

Ocean waves are one of the cleanest and most abundant energy sources on earth, and wave energy has the potential for future power generation. Triboelectric nanogenerator (TENG) technology has recently been proposed as a promising technology to harvest wave energy. In this paper, a theoretical study is performed on a duck-shaped TENG wave harvester recently introduced in our work. To enhance the design of the duck-shaped TENG wave harvester, the mechanical and electrical characteristics of the harvester's overall structure, as well as its inner configuration, are analyzed, respectively, under different wave conditions, to optimize parameters such as duck radius and mass. Furthermore, a comprehensive hybrid 3D model is introduced to quantify the performance of the TENG wave harvester. Finally, the influence of different TENG parameters is validated by comparing the performance of several existing TENG wave harvesters. This study can be applied as a guideline for enhancing the performance of TENG wave energy harvesters.

Potential microbial risk factors related to soil amendments and irrigation water of potato crops.

PubMed

Selma, M V; Allende, A; López-Gálvez, F; Elizaquível, P; Aznar, R; Gil, M I

2007-12-01

This study assesses the potential microbial risk factors related to the use of soil amendments and irrigation water on potato crops, cultivated in one traditional and two intensive farms during two harvest seasons. The natural microbiota and potentially pathogenic micro-organisms were evaluated in the soil amendment, irrigation water, soil and produce. Uncomposted amendments and residual and creek water samples showed the highest microbial counts. The microbial load of potatoes harvested in spring was similar among the tested farms despite the diverse microbial levels of Listeria spp. and faecal coliforms in the potential risk sources. However, differences in total coliform load of potato were found between farms cultivated in the autumn. Immunochromatographic rapid tests and the BAM's reference method (Bacteriological Analytical Manual; AOAC International) were used to detect Escherichia coli O157:H7 from the potential risk sources and produce. Confirmation of the positive results by polymerase chain reaction procedures showed that the immunochromatographic assay was not reliable as it led to false-positive results. The potentially pathogenic micro-organisms of soil amendment, irrigation water and soil samples changed with the harvest seasons and the use of different agricultural practices. However, the microbial load of the produce was not always influenced by these risk sources. Improvements in environmental sample preparation are needed to avoid interferences in the use of immunochromatographic rapid tests. The potential microbial risk sources of fresh produce should be regularly controlled using reliable detection methods to guarantee their microbial safety.

Influence of combined fundamental potentials in a nonlinear vibration energy harvester

NASA Astrophysics Data System (ADS)

Podder, Pranay; Mallick, Dhiman; Amann, Andreas; Roy, Saibal

2016-11-01

Ambient mechanical vibrations have emerged as a viable energy source for low-power wireless sensor nodes aiming the upcoming era of the ‘Internet of Things’. Recently, purposefully induced dynamical nonlinearities have been exploited to widen the frequency spectrum of vibration energy harvesters. Here we investigate some critical inconsistencies between the theoretical formulation and applications of the bistable Duffing nonlinearity in vibration energy harvesting. A novel nonlinear vibration energy harvesting device with the capability to switch amidst individually tunable bistable-quadratic, monostable-quartic and bistable-quartic potentials has been designed and characterized. Our study highlights the fundamentally different large deflection behaviors of the theoretical bistable-quartic Duffing oscillator and the experimentally adapted bistable-quadratic systems, and underlines their implications in the respective spectral responses. The results suggest enhanced performance in the bistable-quartic potential in comparison to others, primarily due to lower potential barrier and higher restoring forces facilitating large amplitude inter-well motion at relatively lower accelerations.

The effect of water harvesting techniques on runoff, sedimentation, and soil properties.

PubMed

Al-Seekh, Saleh H; Mohammad, Ayed G

2009-07-01

This study addressed the hydrological processes of runoff and sedimentation, soil moisture content, and properties under the effect of different water harvesting techniques (treatments). The study was conducted at three sites, representing environmental condition gradients, located in the southern part of the West Bank. For each treatment, the study evaluated soil chemical and physical properties, soil moisture at 30 cm depth, surface runoff and sedimentation at each site. Results showed that runoff is reduced by 65-85% and sedimentation by 58-69% in stone terraces and semi-circle bunds compared to the control at the semi-humid site. In addition, stone terraces and contour ridges significantly reduced the amount of total runoff by 80% and 73%, respectively, at the arid site. Soil moisture content was significantly increased by water harvesting techniques compared to the control in all treatments at the three study sites. In addition, the difference between the control and the water harvesting structures were higher in the arid and semi-arid areas than in the semi-humid area. Soil and water conservation, via utilization of water harvesting structures, is an effective principle for reducing the negative impact of high runoff intensity and subsequently increasing soil moisture storage from rainfall. Jessour systems in the valley and stone terraces were effective in increasing soil moisture storage, prolonging the growing season for natural vegetation, and decreasing the amount of supplemental irrigation required for growing fruit trees.

The Effect of Water Harvesting Techniques on Runoff, Sedimentation, and Soil Properties

NASA Astrophysics Data System (ADS)

Al-Seekh, Saleh H.; Mohammad, Ayed G.

2009-07-01

This study addressed the hydrological processes of runoff and sedimentation, soil moisture content, and properties under the effect of different water harvesting techniques (treatments). The study was conducted at three sites, representing environmental condition gradients, located in the southern part of the West Bank. For each treatment, the study evaluated soil chemical and physical properties, soil moisture at 30 cm depth, surface runoff and sedimentation at each site. Results showed that runoff is reduced by 65-85% and sedimentation by 58-69% in stone terraces and semi-circle bunds compared to the control at the semi-humid site. In addition, stone terraces and contour ridges significantly reduced the amount of total runoff by 80% and 73%, respectively, at the arid site. Soil moisture content was significantly increased by water harvesting techniques compared to the control in all treatments at the three study sites. In addition, the difference between the control and the water harvesting structures were higher in the arid and semi-arid areas than in the semi-humid area. Soil and water conservation, via utilization of water harvesting structures, is an effective principle for reducing the negative impact of high runoff intensity and subsequently increasing soil moisture storage from rainfall. Jessour systems in the valley and stone terraces were effective in increasing soil moisture storage, prolonging the growing season for natural vegetation, and decreasing the amount of supplemental irrigation required for growing fruit trees.

Irrelevant water-management scales for flood prevention, water harvesting and eutrophication control.

NASA Astrophysics Data System (ADS)

Andersson, Jafet; Arheimer, Berit

2017-04-01

This poster will give three examples of popular water-management methods, which we discovered had very little effect in practice because they were applied on irrelevant scales. They all use small scale solutions to large scale problems, and did not provide expected results due to neglecting the magnitude of components in the large-scale water budget. 1) Flood prevention: ponds are considered to be able to buffer water discharge in catchments and was suggested as a measure to reduce the 20-years return floods in an exposed areas in Sweden. However, when experimenting with several ponds allocation and size in a computational model, we found out that ponds had to cover 5-10% of the catchment to convert the 20-yr flood into an average flood. Most effective was to allocate one single water body at the catchment outlet, but this would correspond to 95 km2 which is by far too big to be called a pond. 2) Water Harvesting: At small-scale it is designed to increase water availability and agricultural productivity in smallholder agriculture. On field scale, we show that water harvesting decreases runoff by 55% on average in 62 investigated field-scale trials of drainage area ≤ 1ha in sub-Saharan Africa (Andersson et al., 2011). When upscaling, to river basin scale in South Africa (8-1.8×106 km2), using a scenario approach and the SWAT hydrological model we found that all smallholder fields would not significantly alter downstream river discharge (<0.3% change on average with some effect on low flows). It shows some potential to increase crop yields but only in some water-scarce areas and conditioned on sufficient fertilizers being available (Andersson et al., 2013). 3) Eutrophication control: Constructed wetlands are supposed to remove nutrients from surface water and therefore 1,574 wetlands were constructed in southern Sweden during the years 1996-2006 as a measure to reduce coastal eutrophication. From our detailed calculations, the gross removal was estimated at 140

Living off-grid in an arid environment without a well : can residential and commercial/industrial water harvesting help solve water supply problems?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Axness, Carl L.; Ferrando, Ana

2010-08-01

Our family of three lives comfortably off-grid without a well in an arid region ({approx}9 in/yr, average). This year we expect to achieve water sustainability with harvested or grey water supporting all of our needs (including a garden and trees), except drinking water (about 7 gallons/week). We discuss our implementation and the implication that for an investment of a few thousand dollars, many single family homes could supply a large portion of their own water needs, significantly reducing municipal water demand. Generally, harvested water is very low in minerals and pollutants, but may need treatment for microbes in order tomore » be potable. This may be addressed via filters, UV light irradiation or through chemical treatment (bleach). Looking further into the possibility of commercial water harvesting from malls, big box stores and factories, we ask whether water harvesting could supply a significant portion of potable water by looking at two cities with water supply problems. We look at the implications of separate municipal water lines for potable and clean non-potable uses. Implications on changes to future building codes are explored.« less

Integrated control of landscape irrigation and rainwater harvesting for urban water management

NASA Astrophysics Data System (ADS)

Lee, J. H.; Dhakal, B.; Noh, S.; Seo, D. J.

2016-12-01

Demand for freshwater is increasing rapidly in large and fast-growing urban areas such as the Dallas-Fort Worth Metroplex (DFW). With almost complete reliance on surface water, water supply for DFW is limited by the available storage in the reservoir systems which is now subject to larger variability due to climate change. Landscape irrigation is estimated to account for nearly one-third of all residential water use in the US and as much as 60% in dry climate areas. In landscape irrigation, a large portion of freshwater is commonly lost by sub-optimal practices. If practiced over a large area, one may expect optimized smart irrigation to significantly reduce urban freshwater demand. For increasing on-site water supply, rainwater harvesting (RHW) is particularly attractive in that it conserves potable water while reducing stormwater runoff. Traditional static RWH methods, however, have limited success due to the inefficient water usage. If, on the other hand, lawn irrigation and rainwater harvesting can be optimized as an integrated operation and controlled adaptively to the feedback from the environmental sensors, weather conditions and forecast, one may expect the combined benefits for water conservation and stormwater management to be larger. In this work, we develop a prototype system for integrated control of lawn irrigation and RWH for water conservation and stormwater management, and assess and demonstrate the potential impact and value of the system. For in-situ evaluation, we deploy a wireless sensor network consisting of low-cost off-the-shelf sensors and open-sourced components, and collect observations of temperature, humidity, soil moisture, and solar radiation at the test site at the UTA community garden in Arlington, Texas. We assess the health of the lawn grass using normalized vegetation index (NDVI) from the time lapse images at the site. In this poster, we describe the approach and share the initial results.

Design guidelines of triboelectric nanogenerator for water wave energy harvesters

NASA Astrophysics Data System (ADS)

Ahmed, Abdelsalam; Hassan, Islam; Jiang, Tao; Youssef, Khalid; Liu, Lian; Hedaya, Mohammad; Abu Yazid, Taher; Zu, Jean; Wang, Zhong Lin

2017-05-01

Ocean waves are one of the cleanest and most abundant energy sources on earth, and wave energy has the potential for future power generation. Triboelectric nanogenerator (TENG) technology has recently been proposed as a promising technology to harvest wave energy. In this paper, a theoretical study is performed on a duck-shaped TENG wave harvester recently introduced in our work. To enhance the design of the duck-shaped TENG wave harvester, the mechanical and electrical characteristics of the harvester’s overall structure, as well as its inner configuration, are analyzed, respectively, under different wave conditions, to optimize parameters such as duck radius and mass. Furthermore, a comprehensive hybrid 3D model is introduced to quantify the performance of the TENG wave harvester. Finally, the influence of different TENG parameters is validated by comparing the performance of several existing TENG wave harvesters. This study can be applied as a guideline for enhancing the performance of TENG wave energy harvesters.

Informing water harvesting technology contract design using choice experiments

NASA Astrophysics Data System (ADS)

Tarfasa, Solomon; Brouwer, Roy; Sheremet, Oleg; Bouma, Jetske

2017-10-01

Introducing water harvesting technology is expected to be more effective and last longer if farm households are involved in their design. The main objective of this study is to inform policymakers in Ethiopia about the most important terms and conditions to incentivize farmers to enter into a contractual agreement to invest in water harvesting on their land. In order to test the influence of the way the specific contractual terms and conditions are communicated to farm households, many of whom are illiterate, a split sample approach is applied with and without visual aids for technical, institutional, and economic contract characteristics. Both samples generate significantly different results, highlighting the importance of how information is conveyed to farm households. This pattern is confirmed when examining the self-reported importance attached to the various contract characteristics. Equality Constrained Latent Class models show that contract characteristics for which visual aids were developed are considered more attentively, emphasizing the importance of adequate communication tools in a developing country context where literacy rates are limited to increase water technology innovation uptake and reduce farm household vulnerability to droughts.

The relation of harvesting intensity to changes in soil, soil water, and stream chemistry in a northern hardwood forest, Catskill Mountains, USA

USGS Publications Warehouse

Siemion, Jason; Burns, Douglas A.; Murdoch, Peter S.; Germain, Rene H.

2011-01-01

Previous studies have shown that clearcutting of northern hardwood forests mobilizes base cations, inorganic monomeric aluminum (Alim), and nitrate (NO3--N) from soils to surface waters, but the effects of partial harvests on NO3--N have been less frequently studied. In this study we describe the effects of a series of partial harvests of varying proportions of basal area removal (22%, 28% and 68%) on Alim, calcium (Ca2+), and NO3--N concentrations in soil extracts, soil water, and surface water in the Catskill Mountains of New York, USA. Increases in NO3--N concentrations relative to pre-harvest values were observed within a few months after harvest in soils, soil water, and stream water for all three harvests. Increases in Alim and Ca2+ concentrations were also evident in soil water and stream water over the same time period for all three harvests. The increases in Alim, Ca2+, and NO3--N concentrations in the 68% harvest were statistically significant as measured by comparing the 18-month pre-harvest period with the 18-month post-harvest period, with fewer significant responses in the two harvests of lowest intensity. All three solutes returned to pre-harvest concentrations in soil water and stream water in the two lowest intensity harvests in 2–3 years compared to a full 3 years in the 68% harvest. When the results of this study were combined with those of a previous nearby clearcut and 40% harvest, the post-harvest increases in NO3--N concentrations in stream water and soil water suggest a harvesting level above which the relation between concentration and harvest intensity changes; there was a greater change in concentration per unit change in harvest intensity when basal area removal was greater than 40%. These results indicate that the deleterious effects on aquatic ecosystems previously demonstrated for intensive harvests in northern hardwood forests of northeastern North America that receive high levels of atmospheric N deposition can be greatly

Analysis of relevant proteins from bone graft harvested using the reamer irrigator and aspirator system (RIA) versus iliac crest (IC) bone graft and RIA waste water.

PubMed

Crist, Brett D; Stoker, Aaron M; Stannard, James P; Cook, James L

2016-08-01

Femoral reaming using a Reamer Irrigator Aspirator (RIA) can produce greater than three liters of waste water per procedure, which contains cells and proteins that could promote bone healing. This purpose of this study was to determine the protein profile of RIA waste water and compare protein synthesis by cells harvested via RIA versus iliac crest (IC) bone graft. Bone graft was collected from 30 patients-15 using RIA from the femur and 15 harvested from the iliac crest. Waste water collected during the RIA procedure was analyzed in 12 patients. Cells from each graft were cultured in monolayer using growth media for 14days and inductive media for the next 14days. Media samples were collected on days 14, 21, and 28. Proteins for analysis were chosen based on their potential in bone healing, pro-inflammatory, and anti-inflammatory processes. Proteins present in RIA waste water indicate the potential for clinical use of this filtrate as an adjunct for enhancing bone production, healing, and remodeling. Similarly, cells cultured from RIA bone graft harvests compared favorably to those from iliac crest bone grafts with respect to their potential to aid in bone healing. RIA waste water has potential to serve as an autogenic and allogenic enhancer for bone healing. Continued development of processing protocols for viable commercial use of the waste water and pre-clinical studies designed to evaluate RIA waste water products for bone healing are ongoing. Copyright © 2016 Elsevier Ltd. All rights reserved.

Water and coffee: a systems approach to improving coffee harvesting work in Nicaragua.

PubMed

Silverstein, Barbara A; Bao, Stephen S; Russell, Steven; Stewart, Kate

2012-12-01

The aim of this study was to reduce the physical load on coffee-harvesting workers while maintaining productivity. Coffee is second to oil in commodity trading. Water is becoming scarce worldwide. The global virtual water footprint for one cup of coffee is 140 liters. Shade-grown coffee is one approach to reducing the water footprint. A participatory ergonomics approach was used during two Nicaraguan shade-grown coffee harvesting seasons to reduce the physical load on harvesters with the use of a newly designed bag instead of a basket strapped around the waist. Productivity in the mountainous, shade-grown coffee farms was maintained while physical load on the worker was improved somewhat.Among basket users, 84.2% reported pain in at least one body area compared with 78.9% of bag users (ns). Nonetheless, 74% of participants liked the bag "much better" than the basket. Workers identified ways the bag could be improved further with the use of local materials.These suggestions included (a) reducing the horizontal distance of the bag to reduce reach and (b) having waterproof material on the bag between the worker and the bag to reduce moisture and damage to the berries.There was no difference in productivity between using the bag and using the small basket. Workers are extending this participatory approach to how to get the harvested coffee cherries down the mountain other than carrying 40-kg bags on their backs. The ultimate goal is to make the coffee-harvesting bag design available to harvesters around the world.

Energy Harvesting Characteristics from Water Flow by Piezoelectric Energy Harvester Device Using Cr/Nb Doped Pb(Zr,Ti)O3 Bimorph Cantilever

NASA Astrophysics Data System (ADS)

Kim, Kyoung-Bum; Kim, Chang Il; Jeong, Young Hun; Cho, Jeong-Ho; Paik, Jong-Hoo; Nahm, Sahn; Lim, Jong Bong; Seong, Tae-Hyeon

2013-10-01

A water flow energy harvester, which can convert water flow energy to electric energy, was fabricated for its application to rivers. This harvester can generate power from the bending and releasing motion of piezoelectric bimorph cantilevers. A Pb(Zr0.54Ti0.46)O3 + 0.2 wt % Cr2O3 + 1.0 wt % Nb2O5 (PZT-CN) thick film and a 250-µm-thick stainless steel were used as a bimorph cantilever. The electrical impedance matching was achieved across a resistive load of 1 kΩ. Four bimorph cantilevers can generate power from 5 to 105 rpm. The output powers were steadily increased by increasing the rpm. The maximum output power was 68 mW by 105 rpm. It was found that the water flow energy harvester can generate 58 mW by a flow velocity of (2 m/s) from the stream with the four bimorph cantilevers.

Energy Autonomous Wireless Water Meter with Integrated Turbine Driven Energy Harvester

NASA Astrophysics Data System (ADS)

Becker, P.; Folkmer, B.; Goepfert, R.; Hoffmann, D.; Willmann, A.; Manoli, Y.

2013-12-01

Accurate meter reading is the fundamental task of the home water system for the handling of payments. Meters need to be read correctly, to avoid an effect of adding events that increase unnecessary cost and create customer dissatisfaction. This paper presents a fully integrated wireless, energy autonomous water metering system based on the European Standard EN 13757 "Communication systems for meters and remote reading of meters". The system can be used in multiple water metering scenarios. No maintenance will be required and the system will provide precise and secure data transmission as well as timely and accurate recording of the consumption of water. The identification of any leakages will be improved through the analysis of the actual quantity supplied and recorded by the meters. The system is powered by an energy harvester, based on a water driven turbine wheel that is directly coupled to an electromagnetic energy transducer. The power delivered by the generator is dependent of the amount of flowing water and the pressure in the water pipes. Therefor the power is commonly non-continuous, fluctuant and unstable in the voltage amplitude. To be able to report the meter readings at all times, the system needs to be powered not only in times when the energy harvester delivers energy. Therefor an energy buffer, that stores the harvested energy, is installed to compensate the energy requirement between the actual generator output and the energy consumption of the application. Besides a complete system overview, the presentation will focus on the power management and energy aware battery charging circuitry. The design, fabrication, measuring results and the preparations for field tests in rural and urban environment will be presented and discussed.

Forest fuels and potential fire behaviour 12 years after variable-retention harvest in lodgepole pine

Treesearch

Justin S. Crotteau; Christopher R. Keyes; Elaine K. Sutherland; David K. Wright; Joel M. Egan

2016-01-01

Variable-retention harvesting in lodgepole pine offers an alternative to conventional, even-aged management. This harvesting technique promotes structural complexity and age-class diversity in residual stands and promotes resilience to disturbance. We examined fuel loads and potential fire behaviour 12 years after two modes of variable-retention harvesting (...

Rainwater harvesting in South Africa: Challenges and opportunities

NASA Astrophysics Data System (ADS)

Mwenge Kahinda, J.; Taigbenu, A. E.

Water paucity remains a major threat to poverty, hunger alleviation as well as sustainable development. Innovative water technologies such as rainwater harvesting (RWH) have the potential to improve rural water supply and contribute to the provision of the first 6 kl of water consumed monthly. RWH can also be the solution to South Africa food security by increasing water productivity of dryland agriculture and enabling homestead gardening. Although used for decades in South Africa, rainwater harvesting (RWH) is still far from being utilised to its full potential as unresolved challenges prevent its wide scale adoption. The paper presents the challenges and opportunities to the upscaling of RWH in South Africa. Key challenges preventing the nationwide expansion of RWH are the current water related legislations, the lack of finances and the absence of a national umbrella body that coordinates. While opportunities lie in the worth of knowledge gathered by research projects, funded over the last two decades, on the biophysical and socio-economic impacts of RWH.

Structural Optimization of Triboelectric Nanogenerator for Harvesting Water Wave Energy.

PubMed

Jiang, Tao; Zhang, Li Min; Chen, Xiangyu; Han, Chang Bao; Tang, Wei; Zhang, Chi; Xu, Liang; Wang, Zhong Lin

2015-12-22

Ocean waves are one of the most abundant energy sources on earth, but harvesting such energy is rather challenging due to various limitations of current technologies. Recently, networks formed by triboelectric nanogenerator (TENG) have been proposed as a promising technology for harvesting water wave energy. In this work, a basic unit for the TENG network was studied and optimized, which has a box structure composed of walls made of TENG composed of a wavy-structured Cu-Kapton-Cu film and two FEP thin films, with a metal ball enclosed inside. By combination of the theoretical calculations and experimental studies, the output performances of the TENG unit were investigated for various structural parameters, such as the size, mass, or number of the metal balls. From the viewpoint of theory, the output characteristics of TENG during its collision with the ball were numerically calculated by the finite element method and interpolation method, and there exists an optimum ball size or mass to reach maximized output power and electric energy. Moreover, the theoretical results were well verified by the experimental tests. The present work could provide guidance for structural optimization of wavy-structured TENGs for effectively harvesting water wave energy toward the dream of large-scale blue energy.

Effectiveness of acidic oxidative potential water in preventing bacterial infection in islet transplantation.

PubMed

Miyamoto, M; Inoue, K; Gu, Y; Hoki, M; Haji, S; Ohyanagi, H

1999-01-01

At a number of points in the current procedures of islet isolation and islet culture after the harvesting of donor pancreata, microorganisms could potentially infect the islet preparation. Furthermore, the use of islets from multiple donors can compound the risks of contamination of individual recipients. Acidic oxidative potential water (also termed electrolyzed strong acid solution, function water, or acqua oxidation water), which was developed in Japan, is a strong acid formed on the anode in the electrolysis of water containing a small amount of sodium chloride. It has these physical properties: pH, from 2.3 to 2.7; oxidative-reduction potential, from 1,000 to 1,100 mV; dissolved chlorine, from 30 to 40 ppm; and dissolved oxygen, from 10 to 30 ppm. Because of these properties, acidic oxidative potential water has strong bactericidal effects on all bacteria including methicillin-resistant Staphylococcus aureus (MRSA), viruses including HIV, HBV, HCV, CMV, and fungi as a result of the action of the active oxygen and active chlorine that it contains. We conducted this study to evaluate the effect of acidic oxidative potential water irrigation on bacterial contamination on the harvesting of porcine pancreata from slaughterhouses for islet xenotransplantation by counting the number of pancreatic surface bacteria using the Dip-slide method, and on the results of islet culture; and to evaluate the direct effect on isolated islets when it is used to prevent bacterial contamination by the static incubation test and by morphological examination. Direct irrigation of the pancreas by acidic oxidative potential water was found to be very effective in preventing bacterial contamination, but direct irrigation of isolated islets slightly decreased their viability and function.

Feasibility of Rainwater Harvesting to fulfill potable water demand using quantitative water management in low-lying delta regions of Asia

NASA Astrophysics Data System (ADS)

Mahmood, A.; Hossain, F.

2016-12-01

Low-lying deltas of Asian region are usually densely populated and located in developing countries situated at the downstream end of major rivers. Extensive dam construction by the upstream countries has now caused water scarcity in large portions of low-lying deltas. Most inhabitants depend on shallow tube well for safe drinking water that tend to suffer from water quality issues (e.g. Arsenic contamination). In addition, people also get infected from water borne diseases like Cholera and Typhoid due to lack of safe drinking water. Developing a centralized piped network based water supply system is often not a feasible option in rural regions. Due to social acceptability, environment friendliness, lower capital and maintenance cost, rainwater harvesting can be the most sustainable option to supply safe drinking water in rural areas. In this study, first we estimate the monthly rainfall variability using long precipitation climatology from satellite precipitation data. The upper and lower bounds of monthly harvestable rainwater were estimated for each satellite precipitation grid. Taking this lower bound of monthly harvestable rainwater as input, we use quantitative water management concept to determine the percent of the time of the year potable water demand can be fulfilled. Analysis indicates that a 6 m³ reservoir tank can fulfill the potable water demand of a 6 person family throughout a year in almost all parts of this region.

Microbiological quality of spinach irrigated with reclaimed wastewater and roof-harvest water

USDA-ARS?s Scientific Manuscript database

Aims: The effect of reclaimed wastewater (RCW) and roof-harvest rainwater (RHW) on microbiological quality of irrigated spinach was investigated. Methods and Results: Spinach grown in controlled environment chamber was irrigated by RCW, RHW, or creek water (CW; control water) for four weeks, and th...

Estimating harvested rainwater at greenhouses in south Portugal aquifer Campina de Faro for potential infiltration in Managed Aquifer Recharge.

NASA Astrophysics Data System (ADS)

Costa, Luís; Monteiro, José Paulo; Leitão, Teresa; Lobo-Ferreira, João Paulo; Oliveira, Manuel; Martins de Carvalho, José; Martins de Carvalho, Tiago; Agostinho, Rui

2015-04-01

The Campina de Faro (CF) aquifer system, located on the south coast of Portugal, is an important source of groundwater, mostly used for agriculture purposes. In some areas, this multi-layered aquifer is contaminated with high concentration of nitrates, possibly arising from excessive usage of fertilizers, reaching to values as high as 300 mg/L. In order to tackle this problem, Managed Aquifer Recharge (MAR) techniques are being applied at demonstration scale to improve groundwater quality through aquifer recharge, in both infiltration basins at the river bed of ephemeral river Rio Seco and existing traditional large diameter wells located in this aquifer. In order to assess the infiltration capacity of the existing infrastructures, in particular infiltration basins and large diameter wells at CF aquifer, infiltration tests were performed, indicating a high infiltration capacity of the existing infrastructures. Concerning the sources of water for recharge, harvested rainwater at greenhouses was identified in CF aquifer area as one of the main potential sources for aquifer recharge, once there is a large surface area occupied by these infrastructures at the demo site. This potential source of water could, in some cases, be redirected to the large diameter wells or to the infiltration basins at the riverbed of Rio Seco. Estimates of rainwater harvested at greenhouses were calculated based on a 32 year average rainfall model and on the location of the greenhouses and their surface areas, the latter based on aerial photograph. Potential estimated annual rainwater intercepted by greenhouses at CF aquifer accounts an average of 1.63 hm3/year. Nonetheless it is unlikely that the totality of this amount can be harvested, collected and redirected to aquifer recharge infrastructures, for several reasons, such as the lack of appropriate greenhouse infrastructures, conduits or a close location between greenhouses and large diameter wells and infiltration basins. Anyway, this

Domestic rainwater harvesting to improve water supply in rural South Africa

NASA Astrophysics Data System (ADS)

Mwenge Kahinda, Jean-marc; Taigbenu, Akpofure E.; Boroto, Jean R.

Halving the proportion of people without sustainable access to safe drinking water and basic sanitation, is one of the targets of the 7th Millennium Development Goals (MDGs). In South Africa, with its mix of developed and developing regions, 9.7 million (20%) of the people do not have access to adequate water supply and 16 million (33%) lack proper sanitation services. Domestic Rainwater Harvesting (DRWH), which provides water directly to households enables a number of small-scale productive activities, has the potential to supply water even in rural and peri-urban areas that conventional technologies cannot supply. As part of the effort to achieve the MDGs, the South African government has committed itself to provide financial assistance to poor households for the capital cost of rainwater storage tanks and related works in the rural areas. Despite this financial assistance, the legal status of DRWH remains unclear and DRWH is in fact illegal by strict application of the water legislations. Beyond the cost of installation, maintenance and proper use of the DRWH system to ensure its sustainability, there is risk of waterborne diseases. This paper explores challenges to sustainable implementation of DRWH and proposes some interventions which the South African government could implement to overcome them.

Cell water balance of white button mushrooms (Agaricus bisporus) during its post-harvest lifetime studied by quantitative magnetic resonance imaging.

PubMed

Donker, H C; Van As, H

1999-04-19

A combination of quantitative water density and T2 MRI and changes therein observed after infiltration with 'invisible' Gd-DTPA solution was used to study cell water balances, cell water potentials and cell integrity. This method was applied to reveal the evolution and mechanism of redistribution of water in harvested mushrooms. Even when mushrooms did not lose water during the storage period, a redistribution of water was observed from stipe to cap and gills. When the storage condition resulted in a net loss of water, the stipe lost more water than the cap. The water density in the gill increased, probably due to development of spores. Deterioration effects (i.e. leakage of cells, decrease in osmotic water potential) were found in the outer stipe. They were not found in the cap, even at prolonged storage at 293 K and R.H.=70%. The changes in osmotic potential were partly accounted for by changes in the mannitol concentration. Changes in membrane permeability were also indicated. Cells in the cap had a constant low membrane (water) permeability. They developed a decreasing osmotic potential (more negative), whereas the osmotic potential in the outer stipe increased, together with the permeability of cells.

Water harvesting experience in sub-Saharan Africa - lessons for sustainable intensification of rainfed agriculture and the influence of available soils and rainfall data

NASA Astrophysics Data System (ADS)

Gowin, John; Bunclark, Lisa

2013-04-01

Africa is seen by many as the continent with the greatest potential for agricultural growth, but land degradation and environmental change threaten the African soil resource more severely than in many other regions of the planet. Achieving future food security will depend mainly on increasing production from rainfed agriculture. The challenge of delivering the required sustainable intensification in rainfed agriculture is most acute in the drylands - the semi-arid and dry sub-humid climatic regions. There are two broad strategies for increasing yields under these circumstances: (1) capturing more rainwater and storing it (increasing water availability), and (2) using the available water more effectively by increasing the plant growth and/or reducing non-productive soil evaporation (increasing water productivity). We focus on the first of these options - water harvesting, which is defined as, "the collection and concentration of rainfall runoff, or floodwaters, for plant production". The benefits of water harvesting have been documented from small scale experimental plot studies, but evidence of successful adoption and impact is weak. As a contribution to improving the evidence base, we present results from an investigation conducted in SSA to gather information on progress with efforts to promote adoption of water harvesting. The intention was to investigate in detail the processes and outcomes on a large enough sample area to draw some common conclusions. This was not a comprehensive analysis of all that is happening in each country, nor was it a random sample; this was a purposive sample guided by available baseline information to permit comparative analysis. Water harvesting seems to have made the most progress where techniques can be adopted by individual farmers: in Burkina Faso and Niger micro- scale zaï /tassa and demi-lune systems; in Sudan and Tanzania meso-scale majaruba and teras systems. Macro-scale systems requiring social organisation may offer

Rainwater harvesting and green area retention potential detection using commercial unmanned aerial vehicles

NASA Astrophysics Data System (ADS)

Kamnik, Rok; Grajfoner, Blanka; Butyrin, Andrey; Nekrep Perc, Matjaz

2017-10-01

The objective of this work is to use simple photogrammetry to evaluate rainwater harvesting and green area retention potential in Maribor, Slovenia city centre. Several sources of remote sensing data have been described and a field test with semi-professional drone was performed by means of computer evaluation of rainwater harvesting and green area retention potential. Some of the most important design parameters for rainwater harvesting systems as roof area and slope and available green areas were identified and evaluated. The results have shown that even semi-professional low budget drones can be successfully used for mapping areas of interest. The results of six-minute flight over twelve hectares of Maribor city centre were comparable with professional results of plane remote sensing. Image segmentation from orthomosaic together with elevation model has been used to detect roofs and green areas.

Impact of biomass harvesting on forest soil productivity in the northern Rocky Mountains

Treesearch

Woongsoon Jang; Christopher R. Keyes; Deborah Page-Dumroese

2015-01-01

Biomass harvesting extracts an increased amount of organic matter from forest ecosystems over conventional harvesting. Since organic matter plays a critical role in forest productivity, concerns of potential negative long-term impacts of biomass harvesting on forest productivity (i.e., changing nutrient/water cycling, aggravating soil properties, and compaction) have...

Life cycle assessment of domestic and agricultural rainwater harvesting systems.

PubMed

Ghimire, Santosh R; Johnston, John M; Ingwersen, Wesley W; Hawkins, Troy R

2014-04-01

To further understanding of the environmental implications of rainwater harvesting and its water savings potential relative to conventional U.S. water delivery infrastructure, we present a method to perform life cycle assessment of domestic rainwater harvesting (DRWH) and agricultural rainwater harvesting (ARWH) systems. We also summarize the design aspects of DRWH and ARWH systems adapted to the Back Creek watershed, Virginia. The baseline design reveals that the pump and pumping electricity are the main components of DRWH and ARWH impacts. For nonpotable uses, the minimal design of DRWH (with shortened distribution distance and no pump) outperforms municipal drinking water in all environmental impact categories except ecotoxicity. The minimal design of ARWH outperforms well water in all impact categories. In terms of watershed sustainability, the two minimal designs reduced environmental impacts, from 58% to 78% energy use and 67% to 88% human health criteria pollutants, as well as avoiding up to 20% blue water (surface/groundwater) losses, compared to municipal drinking water and well water. We address potential environmental and human health impacts of urban and rural RWH systems in the region. The Building for Environmental and Economic Sustainability (BEES) model-based life cycle inventory data were used for this study.

Effect of water stress on total biomass, tuber yield, harvest index and water use efficiency in Jerusalem artichoke

USDA-ARS?s Scientific Manuscript database

The objectives of this study were to determine the effect of drought on tuber yield, total biomass, harvest index, water use efficiency of tuber yield (WUEt) and water use efficiency of biomass (WUEb), and to evaluate the differential responses of Jerusalem artichoke (JA) varieties under drought str...

Efficient fog harvesting by Stipagrostis sabulicola (Namib dune bushman grass)

NASA Astrophysics Data System (ADS)

Roth-Nebelsick, A.; Ebner, M.; Miranda, T.

2010-07-01

Stipagrostis sabulicola is an endemic species of the central Namib Desert which settles on extremely arid dune fields. Due to its ability to persistence even during exceptionally dry years it is generally assumed that water supply of this species is substantially based on fog water. In this contribution, the results of a study investigating the capability of S. sabulicola for fog harvesting are presented. For this purpose, stem flow rates of S. sabulicola during fog events, spatial gradient of soil water content (SWC) close to mounds of S. sabulicola and its leaf water potential (LWP) before and after fog events were monitored together with climate parameters. According to the data obtained during this study, S. sabulicola is able to harvest substantial amounts of water by fog catchment from nocturnal fog events. Since culms of S. sabulicola are often stiff with an upright habitus, fog harvesting occurs via stemflow that conducts water directly towards the root zone of a plant. According to this mechanism, the stem runoff is concentrated within the area of the mound. A medium-sized mound of S. sabulicola is able to collect an amount of about 4 l per fog night. This fog harvesting leads to a considerable spatial gradient of soil water content with values decreasing with increasing distance from the mound. As a result of the water input by fog drip, SWC within the mound increases significantly, particularly close to the culm bases where SWC values increased to 2.2 % after a fog event. Due to the uneven distribution of water by stemflow, SWC within a mound shows high spatial heterogeneity which is also illustrated by the numerous outliers and extreme values of SWC within the mound region. This heterogeneity is also due to the fact that several sagging leaves are always present causing fog drip which more or less irregularly scatters moisture. For bare soil outside of a mound, the water content is not substantially increased, amounting to 0.78 % on average during dry

Microalgae harvesting techniques: A review.

PubMed

Singh, Gulab; Patidar, S K

2018-07-01

Microalgae with wide range of commercial applications have attracted a lot of attention of the researchers in the last few decades. However, microalgae utilization is not economically sustainable due to high cost of harvesting. A wide range of solid - liquid separation techniques are available for microalgae harvesting. The techniques include coagulation and flocculation, flotation, centrifugation and filtration or a combination of various techniques. Despite the importance of harvesting to the economics and energy balance, there is no universal harvesting technique for microalgae. Therefore, this review focuses on assessing technical, economical and application potential of various harvesting techniques so as to allow selection of an appropriate technology for cost effectively harvesting of microalgae from their culture medium. Various harvesting and concentrating techniques of microalgae were reviewed to suggest order of suitability of the techniques for four main microalgae applications i.e biofuel, human and animal food, high valued products, and water quality restoration. For deciding the order of suitability, a comparative analysis of various harvesting techniques based on the six common criterions (i.e biomass quality, cost, biomass quantity, processing time, species specific and toxicity) has been done. Based on the order of various techniques vis-a-vis various criteria and preferred order of criteria for various applications, order of suitability of harvesting techniques for various applications has been decided. Among various harvesting techniques, coagulation and flocculation, centrifugation and filtration were found to be most suitable for considered applications. These techniques may be used alone or in combination for increasing the harvesting efficiency. Copyright © 2018 Elsevier Ltd. All rights reserved.

Carbon-Electrode-Tailored All-Inorganic Perovskite Solar Cells To Harvest Solar and Water-Vapor Energy.

PubMed

Duan, Jialong; Hu, Tianyu; Zhao, Yuanyuan; He, Benlin; Tang, Qunwei

2018-05-14

Moisture is the worst enemy for state-of-the-art perovskite solar cells (PSCs). However, the flowing water vapor within nanoporous carbonaceous materials can create potentials. Therefore, it is a challenge to integrate water vapor and solar energies into a single PSC device. We demonstrate herein all-inorganic cesium lead bromide (CsPbBr 3 ) solar cells tailored with carbon electrodes to simultaneously harvest solar and water-vapor energy. Upon interfacial modification and plasma treatment, the bifunctional PSCs yield a maximum power conversion efficiency up to 9.43 % under one sun irradiation according to photoelectric conversion principle and a power output of 0.158 μW with voltage of 0.35 V and current of 0.45 μA in 80 % relative humidity through the flowing potentials at the carbon/water interface. The initial efficiency is only reduced by 2 % on exposing the inorganic PSC with 80 % humidity over 40 days. The successful realization of physical proof-of-concept multi-energy integrated solar cells provides new opportunities of maximizing overall power output. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Potential Ambient Energy-Harvesting Sources and Techniques

ERIC Educational Resources Information Center

Yildiz, Faruk

2009-01-01

Ambient energy harvesting is also known as energy scavenging or power harvesting, and it is the process where energy is obtained from the environment. A variety of techniques are available for energy scavenging, including solar and wind powers, ocean waves, piezoelectricity, thermoelectricity, and physical motions. For example, some systems…

Timber Harvesting Effects After 16 Years in a Tupelo-Cypress Swamp

Treesearch

Paul A. Gellerstedt; W. Michael Aust

2004-01-01

A variety of concerns have been expressed regarding harvesting in forested wetlands. These concerns usually revolve around such issues as potential losses in site productivity, altered wetland functional processes, and development of appropriate best management practices. In 1985 a long-term study was established to evaluate harvest disturbance effects on water quality...

Potential of four corn varieties at different harvest stages for tropical silage production in Malaysia.

PubMed

Nazli, Muhamad Hazim; Abdul Halim, Ridzwan; Abdullah, Amin Mahir; Husin, Ghazali; Samsudin, Anjas Asmara

2018-05-31

Apart from various climatic differences, corn harvest stage and varieties are two major factors that can influence the yield and quality of corn silage in the tropics. A study was conducted to determine the optimum harvest stage of four corn varieties for tropical silage production in Malaysia. Using a split plot design, corn was harvested at four growth stages; silking, milk, dough and dent stages using four varieties; Sweet Corn hybrid 926, Suwan, Breeding Test Line (BTL) 1 and BTL 2. The treatments were then analysed based on the plant growth performance, yield, nutritive and feeding values followed by a financial feasibility study for potential commercialization. Significant differences and interactions were detected across the parameters suggesting varying responses among the varieties towards the harvest stages. Sweet Corn was best harvested early in the dough stage due to high dry matter (DM) yield, digestible nutrient and energy content with low fibre portion. Suwan was recommended to be harvested at the dent stage when it gave the highest DM yield with optimum digestible nutrient and energy content with low acid detergent fibre (ADF). BTL 1 and BTL 2 varieties can either be harvested at dough or dent stages as the crude protein (CP), fibre, DM yield, DM content, digestible nutrient and energy were not significantly different at both stages. Further financial analysis showed that only Sweet Corn production was not financially feasible while Suwan had the best financial appraisal values among the grain varieties. In conclusion, only the grain varieties tested had the potential for silage making according to their optimum harvest stage but Suwan is highly recommended for commercialization as it was the most profitable.

Rainwater Harvesting-based Safe Water Access in Diarrhea-endemic Coastal Communities of Bangladesh under Threats of Climate Change

NASA Astrophysics Data System (ADS)

Akanda, A. S.; Redwan, A. M.; Ali, M. A.; Alam, M.; Jutla, A.; Colwell, R. R.

2014-12-01

feasibility and optimum scales and designs of rainwater-harvesting schemes in areas under changing precipitation patterns and coastal sea-level rise. We present preliminary results based on changing rainfall patterns, water budget analysis, and rainwater harvesting potential.

Charging System Optimization of Triboelectric Nanogenerator for Water Wave Energy Harvesting and Storage.

PubMed

Yao, Yanyan; Jiang, Tao; Zhang, Limin; Chen, Xiangyu; Gao, Zhenliang; Wang, Zhong Lin

2016-08-24

Ocean waves are one of the most promising renewable energy sources for large-scope applications due to the abundant water resources on the earth. Triboelectric nanogenerator (TENG) technology could provide a new strategy for water wave energy harvesting. In this work, we investigated the charging characteristics of utilizing a wavy-structured TENG to charge a capacitor under direct water wave impact and under enclosed ball collision, by combination of theoretical calculations and experimental studies. The analytical equations of the charging characteristics were theoretically derived for the two cases, and they were calculated for various load capacitances, cycle numbers, and structural parameters such as compression deformation depth and ball size or mass. Under the direct water wave impact, the stored energy and maximum energy storage efficiency were found to be controlled by deformation depth, while the stored energy and maximum efficiency can be optimized by the ball size under the enclosed ball collision. Finally, the theoretical results were well verified by the experimental tests. The present work could provide strategies for improving the charging performance of TENGs toward effective water wave energy harvesting and storage.

Watershed sustainability: Downstream effects of timber harvest in the Ozarks of Missouri

USGS Publications Warehouse

Jacobson, Robert B.

2004-01-01

The downstream effects of timber harvest in the Ozarks of Missouri can be evaluated by analogy to other geographic areas and by historical analysis of responses to past land use activities. Based on research from other geographic regions, timber harvest in the Ozarks would be expected to have minor effects on annual water yield and dissolved-phase water quality. The potential exists for haul roads to increase stormflow discharges and sediment yields. Of the possible downstream effects, sediment yield is potentially the most severe and difficult to predict; siting and design of roads are probably the most critical management concerns for minimizing downstream effects. Historical analysis shows that Ozark streams have been destabilized by past land use practices, primarily in the riparian zone. Therefore, present-day timber harvest takes place in a landscape where streams have lowered resilience to disturbance. Predictions of future downstream effects of timber harvest in the Ozarks are complicated by the inherent complexity of cumulative watershed effects and the lack of detailed, long-term instrumental records at appropriate scales.

Effects of Forest Harvesting on Ecosystem Health in the Headwaters of the New York City Water Supply, Catskill Mountains, New York

USGS Publications Warehouse

McHale, Michael R.; Murdoch, Peter S.; Burns, Douglas A.; Baldigo, Barry P.

2008-01-01

The effects of forest clearcutting and selective harvesting on forest soils, soil and stream water chemistry, forest regrowth, and aquatic communities were studied in four small headwater catchments. This research was conducted to identify the sensitivity of forested ecosystems to forest disturbance in the northeastern United States. The study area was in the headwaters of the Neversink Reservoir watershed, part of the New York City water supply system, in the Catskill Mountains of southeastern New York. Two sub-catchments of the Shelter Creek watershed were selectively harvested, one in its northern half and one more heavily in its southern half in 1995?96, the Dry Creek watershed was clearcut in the winter of 1996?97, and the Clear Creek watershed was left undisturbed and monitored as a control site. Monitoring was conducted from 4 years before the harvests until 4 years after the harvests. Clearcutting caused a large release of nitrate (NO3-) from watershed soils and a concurrent release of inorganic monomeric aluminum (Alim), which is toxic to some aquatic biota. The increased soil NO3- concentrations measured after the harvest could be completely accounted for by the decrease in nitrogen (N) uptake by watershed trees, rather than an increase in N mineralization and nitrification. The large increase in stream water NO3- and Alim concentrations caused 100-percent mortality of caged brook trout (Salvelinus fontinalis) during the first year after the clearcut and adversely affected macroinvertebrate communities for 2 years after the harvest. Nutrient uptake and biomass accumulation increased in uncut mature trees after the two selective harvests. There was no increase in stream-water NO3- or Alim concentrations, and so there were no adverse affects on macroinvertebrate or trout communities. The amount of tree biomass that can be removed without causing a sharp increase in stream-water NO3- and Alim stream-water concentrations is unknown, but probably depends on

Analysis of PFAAs in American alligators part 2: Potential dietary exposure of South Carolina hunters from recreationally harvested alligator meat.

PubMed

Tipton, Jessica J; Guillette, Louis J; Lovelace, Susan; Parrott, Benjamin B; Rainwater, Thomas R; Reiner, Jessica L

2017-11-01

Exposure to perfluorinated alkyl acids (PFAAs) has been linked to many harmful health effects including reproductive disorders, developmental delays, and altered liver and kidney function. Most human exposure to environmental contaminants, including PFAAs, occurs through consumption of contaminated food or drinking water. This study uses PFAA data from meat samples collected from recreationally harvested American alligators (Alligator mississippiensis) in South Carolina to assess potential dietary exposure of hunters and their families to PFAAs. Consumption patterns were investigated using intercept surveys of 23 hunters at a wild game meat processor. An exposure scenario using the average consumption frequency, portion size, and median perfluorooctane sulfonic acid (PFOS) concentration in alligator meat from all hunt units found the daily dietary exposure to be 2.11ng/kg body weight per day for an adult human. Dietary PFOS exposure scenarios based on location of harvest suggested the highest daily exposure occurs with alligator meat from the Middle Coastal hunt unit in South Carolina. Although no samples were found to exceed the recommended threshold for no consumption of PFOS found in Minnesota state guidelines, exposure to a mixture of PFAAs found in alligator meat and site-specific exposures based on harvest location should be considered in determining an appropriate guideline for vulnerable populations potentially exposed to PFAAs through consumption of wild alligator meat. Copyright © 2017. Published by Elsevier B.V.

Potential effect of atmospheric warming on grapevine phenology and post-harvest heat accumulation across a range of climates

NASA Astrophysics Data System (ADS)

Hall, Andrew; Mathews, Adam J.; Holzapfel, Bruno P.

2016-09-01

Carbohydrates are accumulated within the perennial structure of grapevines when their production exceeds the requirements of reproduction and growth. The period between harvest and leaf-fall (the post-harvest period) is a key period for carbohydrate accumulation in relatively warmer grape-growing regions. The level of carbohydrate reserves available for utilisation in the following season has an important effect on canopy growth and yield potential and is therefore an important consideration in vineyard management. In a warming climate, the post-harvest period is lengthening and becoming warmer, evidenced through studies in wine regions worldwide that have correlated recent air temperature increases with changing grapevine phenology. Budbreak, flowering, veraison, and harvest have all been observed to be occurring earlier than in previous decades. Additionally, the final stage of the grapevine phenological cycle, leaf-fall, occurs later. This study explored the potential for increased post-harvest carbohydrate accumulation by modelling heat accumulation following harvest dates for the recent climate (1975-2004) and two warmer climate projections with mean temperature anomalies of +1.26 and +2.61 °C. Summaries of post-harvest heat accumulation between harvest and leaf-fall were produced for each of Australia's Geographical Indications (wine regions) to provide comparisons from the base temperatures to projected warmer conditions across a range of climates. The results indicate that for warmer conditions, all regions observe earlier occurring budbreak and harvest as well as increasing post-harvest growing degree days accumulation before leaf-fall. The level of increase varies depending upon starting climatic condition, with cooler regions experiencing the greatest change.

Quantifying health improvements from water quantity enhancement: an engineering perspective applied to rainwater harvesting in West Africa.

PubMed

Fry, Lauren M; Cowden, Joshua R; Watkins, David W; Clasen, Thomas; Mihelcic, James R

2010-12-15

Knowledge of potential benefits resulting from technological interventions informs decision making and planning of water, sanitation, and hygiene programs. The public health field has built a body of literature showing health benefits from improvements in water quality. However, the connection between improvements in water quantity and health is not well documented. Understanding the connection between technological interventions and water use provides insight into this problem. We present a model predicting reductions in diarrhea disease burden when the water demands from hygiene and sanitation improvements are met by domestic rainwater harvesting (DRWH). The model is applied in a case study of 37 West African cities. For all cities, with a total population of over 10 million, we estimate that DRWH with 400 L storage capacity could result in a 9% reduction in disability-affected life years (DALYs). If DRWH is combined with point of use (POU) treatment, this potential impact is nearly doubled, to a 16% reduction in DALYs. Seasonal variability of diarrheal incidence may have a small to moderate effect on the effectiveness of DRWH, depending on the storage volume used. Similar predictions could be made for other interventions that improve water quantity in other locations where disease burden from diarrhea is known.

Potential effects of timber harvest and water management on streamflow dynamics and sediment transport

Treesearch

C. A. Troendle; W. K. Olsen

1994-01-01

The sustainability of aquatic and riparian ecological systems is strongly tied to the dynamics of the streamflow regime. Timber harvest can influence the flow regime by increasing total flow, altering peak discharge rate, and changing the duration of flows of differing frequency of occurrence. These changes in the energy and sediment transporting capability of the...

From phytoaccumulation to post-harvest use of water fern for landfill management.

PubMed

Song, Uhram; Kim, Dae Won; Waldman, Bruce; Lee, Eun Ju

2016-11-01

We examined the potential of Azolla japonica as a remediating plant for leachate channels and post-accumulation use as fertilizer for landfill slope. The harvested biomass of Azolla after one month grown in leachate was 254% that of the initial biomass and the predicted annual harvestable biomass of Azolla using a growth model was 32 times that of the initial biomass. Na, Fe, Mn, Mg, and P were accumulated in Azolla at very high concentrations. Such rapid increase of biomass and high accumulation rates suggest that this plant could be an excellent remediating plant. The post-harvest use of Azolla as compost was studied for the management and use of phytoaccumulating Azolla. Metal contents of Azolla compost were below permissible limits for co-composting material. Nitrogen, organic matter, P, and Mg content of the Azolla compost improved the soil condition of the landfill and enhanced ecophysiological responses of the plants. The application of Azolla compost can improve management of sanitary landfills, including the restoration of vegetation. Considering its ease of harvesting, high accumulation rates, harvestable biomass and suitability for composting, Azolla can provide a suitable solution for sustainable management of leachate channels and landfill slopes. Copyright © 2016. Published by Elsevier Ltd.

Hydrologic and Water Quality Effects of Harvesting and Regeneration of a Drained Pine Forest

Treesearch

Devendra M. Amatya; R. W. Skaggs; C. D. Blanton; J. W. Gilliam

2006-01-01

Data on precipitation, weather, water tables, outflows, and nutrient concentrations from two paired watersheds (D1 - control and D2 - treatment) on a pine forest in Coastal North Carolina were measured during 1988-90 calibration period to characterize the pre-treatment hydrology and water quality. Similarly, measured data from 199 5 (D2 harvested) to 2004 (seven years...

Design Considerations and Economics of Water Harvesting System for Crop Production

NASA Astrophysics Data System (ADS)

Pali, A. K.

2016-06-01

By and large, the design of water harvesting pond is generally based on thumb rules and needs to be upgraded on scientific and engineering principles. In this study, the design procedure of on-farm water harvesting pond has been discussed and two farm ponds of circular, rectangular and square shapes were designed for 50, 60, 75 and 80 % probability of occurrence of rainfall and runoff. Though, the circular shape resulted in the least mean water surface area, but due to not being practicable for agricultural operations, it was discarded. The square shaped ponds resulted in giving least water surface areas as 0.761 ha for the micro watershed of 8.19 ha and as 0.246 ha for the micro watershed of 1.7 ha at 80 % probability level of rainfall and runoff at 80 % level of probability. The storage capacity of the first pond was found as 32,314 m3 and it was 12,962 m3 for the second farm pond. The area to be occupied by the two ponds was worked out as about 11 % of the total land area (8.19 ha) of the first micro watershed and about 18-22 % of the area (1.7 ha) of second micro watershed. Results indicated that the designed size of the first farm pond can be acceptable for construction. The economics of farm pond based agricultural production showed that the highest B/C ratio of 2 and 1.9 were possible for the farm pond designed at 80 and 75 % probability of occurrence of rainfall and runoff respectively.

Hydrologic resilience of a Canadian Foothills watershed to forest harvest

NASA Astrophysics Data System (ADS)

Goodbrand, Amy; Anderson, Axel

2016-04-01

Recent investigations of long-term hydrometeorological, groundwater, and streamflow data from watersheds on the eastern slopes of the Canadian Rocky Mountains showed the streamflow regime was resilient to forest harvest. These watersheds had low levels of harvest relative to their size and a large area of sparsely vegetated alpine talus slopes and exposed bedrock; an area shown to generate the majority of runoff for streamflow. In contrast, watersheds located in the foothills of the Rocky Mountains are of lower relief and typically have harvestable timber throughout the watershed; therefore, these watersheds may be more sensitive to forest disturbance and have increased potential for streamflow response. This project assesses the hydrologic resilience of an Alberta Foothills watershed to forest harvest using a 23-year dataset from the Tri-Creeks Experimental Watershed (Tri-Creeks). Tri-Creeks has been the site of intensive streamflow, groundwater, snow accumulation, and precipitation observations from 1967 - 1990. During the early 1980s, forestry experiments were conducted to compare the effects of timber harvest and riparian buffers, and the effectiveness of timber harvesting ground rules in protecting fisheries and maintaining water resources within three sub-watersheds: Eunice (16.8 km2; control); Deerlick (15.2 km2; 36% streamside timber removal); and, Wampus (28.3 km2; 37% clear-cut). Statistical analyses were used to compare the pre-and post-harvest ratios of treatment to control sub-watershed runoff for: water year, monthly (April - October), snowmelt peak flow, and low flow (10th percentile streamflow) periods as an assessment of hydrologic resilience to forest harvest. The only significant post-harvest change was an increase in water yield during May at Wampus (Mann-Whitney (MW), p<0.05) and Deerlick (MW, p<0.1) Creeks. The lack of change in snowmelt peak flow timing or magnitude was not expected, particularly in Deerlick, which had 36% streamside timber

Monsoon harvests: the living legacies of rainwater harvesting systems in South India.

PubMed

Van Meter, Kimberly J; Basu, Nandita B; Tate, Eric; Wyckoff, Joseph

2014-04-15

Rainwater harvesting, a "soft path" approach toward water management, is increasingly recognized as a key strategy toward ensuring food security and alleviating problems of water scarcity. Interestingly this "modern" approach has been in use for millennia in numerous older civilizations. This article uses India as a case study to explore the social, economic, and environmental dimensions of agricultural rainwater harvesting ponds, and evaluates the viability of these centuries-old systems under current climate and population pressures. A holistic watershed-scale approach that accounts for trade-offs in water availability and socioeconomic wellbeing is recommended for assessing the sustainability of these systems.

Potential impact of harvesting on the population dynamics of two epiphytic bromeliads

NASA Astrophysics Data System (ADS)

Toledo-Aceves, Tarin; Hernández-Apolinar, Mariana; Valverde, Teresa

2014-08-01

Large numbers of epiphytes are extracted from cloud forests for ornamental use and illegal trade in Latin America. We examined the potential effects of different harvesting regimes on the population dynamics of the epiphytic bromeliads Tillandsia multicaulis and Tillandsia punctulata. The population dynamics of these species were studied over a 2-year period in a tropical montane cloud forest in Veracruz, Mexico. Prospective and retrospective analyses were used to identify which demographic processes and life-cycle stages make the largest relative contribution to variation in population growth rate (λ). The effect of simulated harvesting levels on population growth rates was analysed for both species. λ of both populations was highly influenced by survival (stasis), to a lesser extent by growth, and only slightly by fecundity. Vegetative growth played a central role in the population dynamics of these organisms. The λ value of the studied populations did not differ significantly from unity: T. multicaulis λ (95% confidence interval) = 0.982 (0.897-1.060) and T. punctulata λ = 0.967 (0.815-1.051), suggesting population stability. However, numerical simulation of different levels of extraction showed that λ would drop substantially even under very low (2%) harvesting levels. Matrix analysis revealed that T. multicaulis and T. punctulata populations are likely to decline and therefore commercial harvesting would be unsustainable. Based on these findings, management recommendations are outlined.

Re-assessing Rainwater Harvesting Volume by CHIRPS Satellite in Semarang Settlement Area

NASA Astrophysics Data System (ADS)

Prihanto, Yosef; Koestoer, Raldi H.; Sutjiningsih, Dwita

2017-12-01

Semarang City is one of the most influential coastal cities in Java Island. The city is facing increasingly-high water demand due to its development and water problems due to climate change. The spatial physiography and landscape of Semarang City are also exposed the city to water security problem. Hence, rainwater harvesting treatment is an urgent effort to meet the city’s water needs. However, planning, implementation and management of rainwater harvesting are highly depended on multitemporal rainfall data. It has not yet been fully compiled due to limited rain stations. This study aims to examine the extent to which CHIRPS satellite data can be utilized in estimating volume of rainwater harvesting 16 sub-districts in Semarang and determine the water security status. This study uses descriptive statistical method based on spatial analyses. Such method was developed through spatial modeling for rainfall using isohyetal model. The parameters used are rainfall, residential rooftop area, administrative area, population, physiographic and altitude units. Validation is carried out by using monthly 10 rain stations data. The results show level of validity by utilizing CHIRPS Satellite data and mapping rainfall distribution. This study also produces a potential map of distribution rainfall volume that can be harvested in 16 sub-districts of Semarang.

A Twice Electrochemical-Etching Method to Fabricate Superhydrophobic-Superhydrophilic Patterns for Biomimetic Fog Harvest.

PubMed

Yang, Xiaolong; Song, Jinlong; Liu, Junkai; Liu, Xin; Jin, Zhuji

2017-08-18

Superhydrophobic-superhydrophilic patterned surfaces have attracted more and more attention due to their great potential applications in the fog harvest process. In this work, we developed a simple and universal electrochemical-etching method to fabricate the superhydrophobic-superhydrophilic patterned surface on metal superhydrophobic substrates. The anti-electrochemical corrosion property of superhydrophobic substrates and the dependence of electrochemical etching potential on the wettability of the fabricated dimples were investigated on Al samples. Results showed that high etching potential was beneficial for efficiently producing a uniform superhydrophilic dimple. Fabrication of long-term superhydrophilic dimples on the Al superhydrophobic substrate was achieved by combining the masked electrochemical etching and boiling-water immersion methods. A long-term wedge-shaped superhydrophilic dimple array was fabricated on a superhydrophobic surface. The fog harvest test showed that the surface with a wedge-shaped pattern array had high water collection efficiency. Condensing water on the pattern was easy to converge and depart due to the internal Laplace pressure gradient of the liquid and the contact angle hysteresis contrast on the surface. The Furmidge equation was applied to explain the droplet departing mechanism and to control the departing volume. The fabrication technique and research of the fog harvest process may guide the design of new water collection devices.

Geotechnology and landscape ecology applied to the selection of potential forest fragments for seed harvesting.

PubMed

Santos, Alexandre Rosa Dos; Antonio Alvares Soares Ribeiro, Carlos; de Oliveira Peluzio, Telma Machado; Esteves Peluzio, João Batista; de Queiroz, Vagner Tebaldi; Figueira Branco, Elvis Ricardo; Lorenzon, Alexandre Simões; Domingues, Getulio Fonseca; Marcatti, Gustavo Eduardo; de Castro, Nero Lemos Martins; Teixeira, Thaisa Ribeiro; Dos Santos, Gleissy Mary Amaral Dino Alves; Santos Mota, Pedro Henrique; Ferreira da Silva, Samuel; Vargas, Rozimelia; de Carvalho, José Romário; Macedo, Leandro Levate; da Silva Araújo, Cintia; de Almeida, Samira Luns Hatum

2016-12-01

The Atlantic Forest biome is recognized for its biodiversity and is one of the most threatened biomes on the planet, with forest fragmentation increasing due to uncontrolled land use, land occupation, and population growth. The most serious aspect of the forest fragmentation process is the edge effect and the loss of biodiversity. In this context, the aim of this study was to evaluate the dynamics of forest fragmentation and select potential forest fragments with a higher degree of conservation for seed harvesting in the Itapemirim river basin, Espírito Santo State, Brazil. Image classification techniques, forest landscape ecology, and multi-criteria analysis were used to evaluate the evolution of forest fragmentation to develop the landscape metric indexes, and to select potential forest fragments for seed harvesting for the years 1985 and 2013. According to the results, there was a reduction of 2.55% of the occupancy of the fragments in the basin between the years 1985 and 2013. For the years 1985 and 2013, forest fragment units 2 and 3 were spatialized with a high potential for seed harvesting, representing 6.99% and 16.01% of the total fragments, respectively. The methodology used in this study has the potential to be used to support decisions for the selection of potential fragments for seed harvesting because selecting fragments in different environments by their spatial attributes provides a greater degree of conservation, contributing to the protection and conscious management of the forests. The proposed methodology can be adapted to other areas and different biomes of the world. Copyright © 2016 Elsevier Ltd. All rights reserved.

The effect of aspen harvest and growth on water yield in Minnesota

Treesearch

Elon S. Verry

1987-01-01

Annual water yield increased following the clearcutting of a mature aspen forest in years 1-9 and year 14 of subsequent aspen regrowth. Maximum increases of 85, 117, and 88 mm year-l occurred during the first 3 years of regrowth. Increases in streamflow volumes from snowmelt and early spring rains were minimal and more variable after harvest and...

Carriage of Vibrio species by shrimps harvested from the coastal waters of South West Cameroon.

PubMed

Ndip, R N; Akoachere, J F T K; Mokosso, D K; Ndip, L M; Anyangwe, I A N

2002-03-01

To determine the prevalence of Vibrio spp in unprocessed shrimps and their susceptibility to antibiotics. A prospective study of Vibrio spp associated with shrimps harvested from the coastal waters of South West Cameroon. A laboratory based study at the Department of Life Sciences, University of Buea. Two hundred and thirty six shrimps harvested from the coastal towns of Limbe and Tiko, Cameroon, were examined for the prevalence of Vibrio spp using standard microbiologic procedures. The antibiotic sensitivity of isolates was determined using the Kirby-Bauer disc diffusion technique. Of the 236 shrimps examined, 73 (30.9%) were contaminated with Vibrio spp. Further, a total of 125 Vibrio strains were isolated from the contaminated shrimps. Of this number, 33 (26.4%) were V. cholerae, 55 (44%) V. parahaemolyticus, 34 (27.2%) V. alginolyticus and three (2.4%) V. vulnificus. Antibiotic susceptibility generally ranged from 68.8% for polymyxin B to 99.2% for gentamycin. Multiple resistant strains were noted, especially with V. parahaemolyticus and V. alginolyticus Shrimps maintain a reservoir of potential Vibrio spp in the coastal area of South West Cameroon. This finding is of epidemiologic and clinical significance.

Stand, Harvest, and Equipment Interactions in Simulated Harvesting Prescriptions

Treesearch

Jingxin Wang; W. Dale Greene; Bryce J. Stokes

1998-01-01

We evaluated potential interactions of stand type, harvesting method, and equipment in an experiment using interactive simulation. We examined three felling methods (chain saw, feller-buncher, harvester) and two extraction methods (grapple skidder and forwarder) performing clearcuts, sheltenvood cuts, and single-tree selection cuts in both an uneven-aged natural stand...

Energy-harvesting potential of automobile suspension

NASA Astrophysics Data System (ADS)

Múčka, Peter

2016-12-01

This study is aimed quantify dissipated power in a damper of automobile suspension to predict energy harvesting potential of a passenger car more accurately. Field measurements of power dissipation in a regenerative damper are still rare. The novelty is in using the broad database of real road profiles, a 9 degrees-of-freedom full-car model with real parameters, and a tyre-enveloping contact model. Results were presented as a function of road surface type, velocity and road roughness characterised by International Roughness Index. Results were calculated for 1600 test sections of a total length about 253.5 km. Root mean square of a dissipated power was calculated from 19 to 46 W for all four suspension dampers and velocity 60 km/h and from 24 to 58 W for velocity 90 km/h. Results were compared for a full-car model with a tyre-enveloping road contact, full-car and quarter-car models with a tyre-road point contact. Mean difference among three models in calculated power was a few per cent.

Stochastic resonance energy harvesting for a rotating shaft subject to random and periodic vibrations: influence of potential function asymmetry and frequency sweep

NASA Astrophysics Data System (ADS)

Kim, Hongjip; Che Tai, Wei; Zhou, Shengxi; Zuo, Lei

2017-11-01

Stochastic resonance is referred to as a physical phenomenon that is manifest in nonlinear systems whereby a weak periodic signal can be significantly amplified with the aid of inherent noise or vice versa. In this paper, stochastic resonance is considered to harvest energy from two typical vibrations in rotating shafts: random whirl vibration and periodic stick-slip vibration. Stick-slip vibrations impose a constant offset in centrifugal force and distort the potential function of the harvester, leading to potential function asymmetry. A numerical analysis based on a finite element method was conducted to investigate stochastic resonance with potential function asymmetry. Simulation results revealed that a harvester with symmetric potential function generates seven times higher power than that with asymmetric potential function. Furthermore, a frequency-sweep analysis also showed that stochastic resonance has hysteretic behavior, resulting in frequency difference between up-sweep and down-sweep excitations. An electromagnetic energy harvesting system was constructed to experimentally verify the numerical analysis. In contrast to traditional stochastic resonance harvesters, the proposed harvester uses magnetic force to compensate the offset in the centrifugal force. System identification was performed to obtain the parameters needed in the numerical analysis. With the identified parameters, the numerical simulations showed good agreement with the experiment results with around 10% error, which verified the effect of potential function asymmetry and frequency sweep excitation condition on stochastic resonance. Finally, attributed to compensating the centrifugal force offset, the proposed harvester generated nearly three times more open-circuit output voltage than its traditional counterpart.

Coupled Triboelectric Nanogenerator Networks for Efficient Water Wave Energy Harvesting.

PubMed

Xu, Liang; Jiang, Tao; Lin, Pei; Shao, Jia Jia; He, Chuan; Zhong, Wei; Chen, Xiang Yu; Wang, Zhong Lin

2018-02-27

Water wave energy is a promising clean energy source, which is abundant but hard to scavenge economically. Triboelectric nanogenerator (TENG) networks provide an effective approach toward massive harvesting of water wave energy in oceans. In this work, a coupling design in TENG networks for such purposes is reported. The charge output of the rationally linked units is over 10 times of that without linkage. TENG networks of three different connecting methods are fabricated and show better performance for the ones with flexible connections. The network is based on an optimized ball-shell structured TENG unit with high responsivity to small agitations. The dynamic behavior of single and multiple TENG units is also investigated comprehensively to fully understand their performance in water. The study shows that a rational design on the linkage among the units could be an effective strategy for TENG clusters to operate collaboratively for reaching a higher performance.

Photocatalytic Water-Splitting Enhancement by Sub-Bandgap Photon Harvesting.

PubMed

Monguzzi, Angelo; Oertel, Amadeus; Braga, Daniele; Riedinger, Andreas; Kim, David K; Knüsel, Philippe N; Bianchi, Alberto; Mauri, Michele; Simonutti, Roberto; Norris, David J; Meinardi, Francesco

2017-11-22

Upconversion is a photon-management process especially suited to water-splitting cells that exploit wide-bandgap photocatalysts. Currently, such catalysts cannot utilize 95% of the available solar photons. We demonstrate here that the energy-conversion yield for a standard photocatalytic water-splitting device can be enhanced under solar irradiance by using a low-power upconversion system that recovers part of the unutilized incident sub-bandgap photons. The upconverter is based on a sensitized triplet-triplet annihilation mechanism (sTTA-UC) obtained in a dye-doped elastomer and boosted by a fluorescent nanocrystal/polymer composite that allows for broadband light harvesting. The complementary and tailored optical properties of these materials enable efficient upconversion at subsolar irradiance, allowing the realization of the first prototype water-splitting cell assisted by solid-state upconversion. In our proof-of concept device the increase of the performance is 3.5%, which grows to 6.3% if concentrated sunlight (10 sun) is used. Our experiments show how the sTTA-UC materials can be successfully implemented in technologically relevant devices while matching the strict requirements of clean-energy production.

Harvesting wood for energy.

Treesearch

Rodger A. Arola; Edwin W. Miyata

1981-01-01

Illustrates the potential of harvesting wood for industrial energy, based on the results of five harvesting studies. Presents information on harvesting operations, equipment costs, and productivity. Discusses mechanized thinning of hardwoods, clearcutting of low-value stands and recovery of hardwood tops and limbs. Also includes basic information on the physical and...

Water table response to harvesting and simulated emerald ash borer mortality in black ash wetlands in Minnesota, USA

Treesearch

Robert A. Slesak; Christian F. Lenhart; Kenneth N. Brooks; Anthony W. D' Amato; Brian J. Palik

2014-01-01

Black ash wetlands are seriously threatened because of the invasive emerald ash borer (EAB). Wetland hydrology is likely to be modified following ash mortality, but the magnitude of hydrological impact following loss via EAB and alternative mitigation harvests is not clear. Our objective was to assess the water table response to simulated EAB and harvesting to...

A new harvest operation cost model to evaluate forest harvest layout alternatives

Treesearch

Mark M. Clark; Russell D. Meller; Timothy P. McDonald; Chao Chi Ting

1997-01-01

The authors develop a new model for harvest operation costs that can be used to evaluate stands for potential harvest. The model is based on felling, extraction, and access costs, and is unique in its consideration of the interaction between harvest area shapes and access roads. The scientists illustrate the model and evaluate the impact of stand size, volume, and road...

Cutaneous water collection by a moisture-harvesting lizard, the thorny devil (Moloch horridus).

PubMed

Comanns, Philipp; Withers, Philip C; Esser, Falk J; Baumgartner, Werner

2016-11-01

Moisture-harvesting lizards, such as the Australian thorny devil, Moloch horridus, have the remarkable ability to inhabit arid regions. Special skin structures, comprising a micro-structured surface with capillary channels in between imbricate overlapping scales, enable the lizard to collect water by capillarity and transport it to the mouth for ingestion. The ecological role of this mechanism is the acquisition of water from various possible sources such as rainfall, puddles, dew, condensation on the skin, or absorption from moist sand, and we evaluate here the potential of these various sources for water uptake by M. horridus The water volume required to fill the skin capillary system is 3.19% of body mass. Thorny devils standing in water can fill their capillary system and then drink from this water, at approximately 0.7 µl per jaw movement. Thorny devils standing on nearly saturated moist sand could only fill the capillary channels to 59% of their capacity, and did not drink. However, placing moist sand on skin replicas showed that the capillary channels could be filled from moist sand when assisted by gravity, suggesting that their field behaviour of shovelling moist sand onto the dorsal skin might fill the capillary channels and enable drinking. Condensation facilitated by thermal disequilibrium between a cool thorny devil and warm moist air provided skin capillary filling to approximately 0.22% of body weight, which was insufficient for drinking. Our results suggest that rain and moist sand seem to be ecologically likely water sources for M. horridus on a regular basis. © 2016. Published by The Company of Biologists Ltd.

Estimating water consumption of potential natural vegetation on global dry lands: building an LCA framework for green water flows.

PubMed

Núñez, Montserrat; Pfister, Stephan; Roux, Philippe; Antón, Assumpció

2013-01-01

This study aimed to provide a framework for assessing direct soil-water consumption, also termed green water in the literature, in life cycle assessment (LCA). This was an issue that LCA had not tackled before. The approach, which is applied during the life cycle inventory phase (LCI), consists of quantifying the net change in the evapo(transpi)ration of the production system compared to the natural reference situation. Potential natural vegetation (PNV) is used as the natural reference situation. In order to apply the method, we estimated PNV evapotranspiration adapted to local biogeographic conditions, on global dry lands, where soil-water consumption impacts can be critical. Values are reported at different spatial aggregation levels: 10-arcmin global grid, ecoregions (501 units), biomes (14 units), countries (124 units), continents, and a global average, to facilitate the assessment for different spatial information detail levels available in the LCI. The method is intended to be used in rain-fed agriculture and rainwater harvesting contexts, which includes direct soil moisture uptake by plants and rainwater harvested and then reused in production systems. The paper provides the necessary LCI method and data for further development of impact assessment models and characterization factors to evaluate the environmental effects of the net change in evapo(transpi)ration.

Effects of forest harvest on stream-water quality and nitrogen cycling in the Caspar Creek watershed

Treesearch

Randy A. Dahlgren

1998-01-01

The effects of forest harvest on stream-water quality and nitrogen cycling were examined for a redwood/Douglas-fir ecosystem in the North Fork, Caspar Creek experimental watershed in northern California. Stream-water samples were collected from treated (e.g., clearcut) and reference (e.g., noncut) watersheds, and from various locations downstream from the treated...

50 CFR 300.132 - Lobster harvest limitations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Lobster harvest limitations. 300.132... FISHERIES REGULATIONS Vessels of the United States Fishing in Colombian Treaty Waters § 300.132 Lobster harvest limitations. (a) Berried lobsters. A berried (egg-bearing) lobster in treaty waters may not be...

50 CFR 300.132 - Lobster harvest limitations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 9 2011-10-01 2011-10-01 false Lobster harvest limitations. 300.132... FISHERIES REGULATIONS Vessels of the United States Fishing in Colombian Treaty Waters § 300.132 Lobster harvest limitations. (a) Berried lobsters. A berried (egg-bearing) lobster in treaty waters may not be...

Energy Harvesting from Salinity Gradient

NASA Astrophysics Data System (ADS)

Muhthassim, B.; Thian, X. K.; Hasan, K. N. Md

2018-04-01

Abstract: Energy harvesting from salt water received attention started back in 1970s’, but due to varying interests in the field and the growing potentials of other more promising sources, more work was required to fully establish it. This paper aims at identifying existing techniques of energy harvesting and the methodology involved determining an effective technique for small scale applications of the method. Capacitive deionization technique which involves electrochemical reaction was chosen for further analysis. The experiment was conducted to analyze factors affecting its performance including the electrode and the electrolyte. Combination electrode of carbon/aluminium, copper/aluminium and carbon/copper were selected and tested with different concentration of salty water. From the experiment, copper and aluminum electrodes were found to be the most effective among the rest. A DC-DC boost converter was used to step-up the voltage. Physical implementation of the circuit was done and the circuit was tested in which an input voltage of 1.022 V was boosted to 1.255 V. The efficiency of the boost converter was 38.17 % based on input power and output power obtained.

Fog Harvesting with Harps.

PubMed

Shi, Weiwei; Anderson, Mark J; Tulkoff, Joshua B; Kennedy, Brook S; Boreyko, Jonathan B

2018-04-11

Fog harvesting is a useful technique for obtaining fresh water in arid climates. The wire meshes currently utilized for fog harvesting suffer from dual constraints: coarse meshes cannot efficiently capture microscopic fog droplets, whereas fine meshes suffer from clogging issues. Here, we design and fabricate fog harvesters comprising an array of vertical wires, which we call "fog harps". Under controlled laboratory conditions, the fog-harvesting rates for fog harps with three different wire diameters were compared to conventional meshes of equivalent dimensions. As expected for the mesh structures, the mid-sized wires exhibited the largest fog collection rate, with a drop-off in performance for the fine or coarse meshes. In contrast, the fog-harvesting rate continually increased with decreasing wire diameter for the fog harps due to efficient droplet shedding that prevented clogging. This resulted in a 3-fold enhancement in the fog-harvesting rate for the harp design compared to an equivalent mesh.

Control of electro-chemical processes using energy harvesting materials and devices.

PubMed

Zhang, Yan; Xie, Mengying; Adamaki, Vana; Khanbareh, Hamideh; Bowen, Chris R

2017-12-11

Energy harvesting is a topic of intense interest that aims to convert ambient forms of energy such as mechanical motion, light and heat, which are otherwise wasted, into useful energy. In many cases the energy harvester or nanogenerator converts motion, heat or light into electrical energy, which is subsequently rectified and stored within capacitors for applications such as wireless and self-powered sensors or low-power electronics. This review covers the new and emerging area that aims to directly couple energy harvesting materials and devices with electro-chemical systems. The harvesting approaches to be covered include pyroelectric, piezoelectric, triboelectric, flexoelectric, thermoelectric and photovoltaic effects. These are used to influence a variety of electro-chemical systems such as applications related to water splitting, catalysis, corrosion protection, degradation of pollutants, disinfection of bacteria and material synthesis. Comparisons are made between the range harvesting approaches and the modes of operation are described. Future directions for the development of electro-chemical harvesting systems are highlighted and the potential for new applications and hybrid approaches are discussed.

Conceptual approach on harvesting PV dissipated heat for enhancing water evaporation

NASA Astrophysics Data System (ADS)

Latiff, N. Abdul; Ya'acob, M. E.; Yunos, Khairul Faezah Md.

2017-09-01

The fluctuating sun radiation in tropical climate conditions has significantly affected the output performance of the PV array and also processes related to direct-sun drying. Apart from this, the dissipated heat under PV array projected from photonic effects of generating electricity is currently wasted to the environment. This study shares some conceptual idea on a new approach for harvesting the dissipated heat energy from PV arrays for the purpose of enhancing water evaporation process. Field measurements for ambient temperature (Ta) and PV bottom surface temperature (FFb) are measured and recorded for calculating the evaporation rates at different condition in real time. The waste heat dissipated in this condition is proposed as a medium to increase evaporation thru speeding up the water condensation process. The significant increase of water evaporation rate based on Penman equation supports the idea of integration with landed PV array structures.

Potential water yield response following clearcut harvesting on north and south slopes in northern Idaho

Treesearch

Richard G. Cline; Harold F. Haupt; Gaylon S. Campbell

1977-01-01

The hydrologic response of small clearcuts on north and south slopes in northern Idaho was investigated. On the north slope, substantial gains (27 to 35 cm) in potential water yield per year resulted from (a) removal of transpiring surfaces associated with plant cover, (b) elimination of snow interception by a closed-canopied forest, and (C) delayed reoccupation of the...

Ecological impacts of energy-wood harvests: lessons from whole-tree harvesting and natural disturbance

USGS Publications Warehouse

Berger, Alaina L.; Palik, Brian; D'Amato, Anthony W.; Fraver, Shawn; Bradford, John B.; Nislow, Keith H.; King, David; Brooks, Robert T.

2013-01-01

Recent interest in using forest residues and small-diameter material for biofuels is generating a renewed focus on harvesting impacts and forest sustainability. The rich legacy of research from whole-tree harvesting studies can be examined in light of this interest. Although this research largely focused on consequences for forest productivity, in particular carbon and nutrient pools, it also has relevance for examining potential consequences for biodiversity and aquatic ecosystems. This review is framed within a context of contrasting ecosystem impacts from whole-tree harvesting because it represents a high level of biomass removal. Although whole-tree harvesting does not fully use the nonmerchantable biomass available, it indicates the likely direction and magnitude of impacts that can occur through energy-wood harvesting compared with less-intensive conventional harvesting and to dynamics associated with various natural disturbances. The intent of this comparison is to gauge the degree of departure of energy-wood harvesting from less intensive conventional harvesting. The review of the literature found a gradient of increasing departure in residual structural conditions that remained in the forest when conventional and whole-tree harvesting was compared with stand-replacing natural disturbance. Important stand- and landscape-level processes were related to these structural conditions. The consequence of this departure may be especially potent because future energy-wood harvests may more completely use a greater range of forest biomass at potentially shortened rotations, creating a great need for research that explores the largely unknown scale of disturbance that may apply to our forest ecosystems.

Genetic and biochemical analysis reveals linked QTLs determining natural variation for fruit post-harvest water loss in pepper (Capsicum).

PubMed

Popovsky-Sarid, Sigal; Borovsky, Yelena; Faigenboim, Adi; Parsons, Eugene P; Lohrey, Gregory T; Alkalai-Tuvia, Sharon; Fallik, Elazar; Jenks, Matthew A; Paran, Ilan

2017-02-01

Molecular markers linked to QTLs controlling post-harvest fruit water loss in pepper may be utilized to accelerate breeding for improved shelf life and inhibit over-ripening before harvest. Bell pepper (Capsicum annuum L.) is an important vegetable crop world-wide. However, marketing is limited by the relatively short shelf life of the fruit due to water loss and decay that occur during prolonged storage. Towards breeding pepper with reduced fruit post-harvest water loss (PWL), we studied the genetic, physiological and biochemical basis for natural variation of PWL. We performed quantitative trait locus (QTL) mapping of fruit PWL in multiple generations of an interspecific cross of pepper, which resulted in the identification of two linked QTLs on chromosome 10 that control the trait. We further developed near-isogenic lines (NILs) for characterization of the QTL effects. Transcriptome analysis of the NILs allowed the identification of candidate genes associated with fruit PWL-associated traits such as cuticle biosynthesis, cell wall metabolism and fruit ripening. Significant differences in PWL between the NILs in the immature fruit stage, differentially expressed cuticle-associated genes and differences in the content of specific chemical constituents of the fruit cuticle, indicated a likely influence of cuticle composition on the trait. Reduced PWL in the NILs was associated with delayed over-ripening before harvest, low total soluble solids before storage, and reduced fruit softening after storage. Our study enabled a better understanding of the genetic and biological processes controlling natural variation in fruit PWL in pepper. Furthermore, the genetic materials and molecular markers developed in this study may be utilized to breed peppers with improved shelf life and inhibited over-ripening before harvest.

Moisture harvesting and water transport through specialized micro-structures on the integument of lizards

PubMed Central

Comanns, Philipp; Effertz, Christian; Hischen, Florian; Staudt, Konrad; Böhme, Wolfgang

2011-01-01

Summary Several lizard species that live in arid areas have developed special abilities to collect water with their bodies' surfaces and to ingest the so collected moisture. This is called rain- or moisture-harvesting. The water can originate from air humidity, fog, dew, rain or even from humid soil. The integument (i.e., the skin plus skin derivatives such as scales) has developed features so that the water spreads and is soaked into a capillary system in between the reptiles' scales. Within this capillary system the water is transported to the mouth where it is ingested. We have investigated three different lizard species which have developed the ability for moisture harvesting independently, viz. the Australian thorny devil (Moloch horridus), the Arabian toadhead agama (Phrynocephalus arabicus) and the Texas horned lizard (Phrynosoma cornutum). All three lizards have a honeycomb like micro ornamentation on the outer surface of the scales and a complex capillary system in between the scales. By investigation of individual scales and by producing and characterising polymer replicas of the reptiles' integuments, we found that the honeycomb like structures render the surface superhydrophilic, most likely by holding a water film physically stable. Furthermore, the condensation of air humidity is improved on this surface by about 100% in comparison to unstructured surfaces. This allows the animals to collect moisture with their entire body surface. The collected water is transported into the capillary system. For Phrynosoma cornutum we found the interesting effect that, in contrast to the other two investigated species, the water flow in the capillary system is not uniform but directed to the mouth. Taken together we found that the micro ornamentation yields a superhydrophilic surface, and the semi-tubular capillaries allow for an efficient passive – and for Phrynosoma directed – transport of water. PMID:21977432

Moisture harvesting and water transport through specialized micro-structures on the integument of lizards.

PubMed

Comanns, Philipp; Effertz, Christian; Hischen, Florian; Staudt, Konrad; Böhme, Wolfgang; Baumgartner, Werner

2011-01-01

Several lizard species that live in arid areas have developed special abilities to collect water with their bodies' surfaces and to ingest the so collected moisture. This is called rain- or moisture-harvesting. The water can originate from air humidity, fog, dew, rain or even from humid soil. The integument (i.e., the skin plus skin derivatives such as scales) has developed features so that the water spreads and is soaked into a capillary system in between the reptiles' scales. Within this capillary system the water is transported to the mouth where it is ingested. We have investigated three different lizard species which have developed the ability for moisture harvesting independently, viz. the Australian thorny devil (Moloch horridus), the Arabian toadhead agama (Phrynocephalus arabicus) and the Texas horned lizard (Phrynosoma cornutum). All three lizards have a honeycomb like micro ornamentation on the outer surface of the scales and a complex capillary system in between the scales. By investigation of individual scales and by producing and characterising polymer replicas of the reptiles' integuments, we found that the honeycomb like structures render the surface superhydrophilic, most likely by holding a water film physically stable. Furthermore, the condensation of air humidity is improved on this surface by about 100% in comparison to unstructured surfaces. This allows the animals to collect moisture with their entire body surface. The collected water is transported into the capillary system. For Phrynosoma cornutum we found the interesting effect that, in contrast to the other two investigated species, the water flow in the capillary system is not uniform but directed to the mouth. Taken together we found that the micro ornamentation yields a superhydrophilic surface, and the semi-tubular capillaries allow for an efficient passive - and for Phrynosoma directed - transport of water.

Potential of water surface-floating microalgae for biodiesel production: Floating-biomass and lipid productivities.

PubMed

Muto, Masaki; Nojima, Daisuke; Yue, Liang; Kanehara, Hideyuki; Naruse, Hideaki; Ujiro, Asuka; Yoshino, Tomoko; Matsunaga, Tadashi; Tanaka, Tsuyoshi

2017-03-01

Microalgae have been accepted as a promising feedstock for biodiesel production owing to their capability of converting solar energy into lipids through photosynthesis. However, the high capital and operating costs, and high energy consumption, are hampering commercialization of microalgal biodiesel. In this study, the surface-floating microalga, strain AVFF007 (tentatively identified as Botryosphaerella sudetica), which naturally forms a biofilm on surfaces, was characterized for use in biodiesel production. The biofilm could be conveniently harvested from the surface of the water by adsorbing onto a polyethylene film. The lipid productivity of strain AVFF007 was 46.3 mg/L/day, allowing direct comparison to lipid productivities of other microalgal species. The moisture content of the surface-floating biomass was 86.0 ± 1.2%, which was much lower than that of the biomass harvested using centrifugation. These results reveal the potential of this surface-floating microalgal species as a biodiesel producer, employing a novel biomass harvesting and dewatering strategy. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Reevaluation of health risk benchmark for sustainable water practice through risk analysis of rooftop-harvested rainwater.

PubMed

Lim, Keah-Ying; Jiang, Sunny C

2013-12-15

Health risk concerns associated with household use of rooftop-harvested rainwater (HRW) constitute one of the main impediments to exploit the benefits of rainwater harvesting in the United States. However, the benchmark based on the U.S. EPA acceptable annual infection risk level of ≤1 case per 10,000 persons per year (≤10(-4) pppy) developed to aid drinking water regulations may be unnecessarily stringent for sustainable water practice. In this study, we challenge the current risk benchmark by quantifying the potential microbial risk associated with consumption of HRW-irrigated home produce and comparing it against the current risk benchmark. Microbial pathogen data for HRW and exposure rates reported in literature are applied to assess the potential microbial risk posed to household consumers of their homegrown produce. A Quantitative Microbial Risk Assessment (QMRA) model based on worst-case scenario (e.g. overhead irrigation, no pathogen inactivation) is applied to three crops that are most popular among home gardeners (lettuce, cucumbers, and tomatoes) and commonly consumed raw. The infection risks of household consumers attributed to consumption of these home produce vary with the type of produce. The lettuce presents the highest risk, which is followed by tomato and cucumber, respectively. Results show that the 95th percentile values of infection risk per intake event of home produce are one to three orders of magnitude (10(-7) to 10(-5)) lower than U.S. EPA risk benchmark (≤10(-4) pppy). However, annual infection risks under the same scenario (multiple intake events in a year) are very likely to exceed the risk benchmark by one order of magnitude in some cases. Estimated 95th percentile values of the annual risk are in the 10(-4) to 10(-3) pppy range, which are still lower than the 10(-3) to 10(-1) pppy risk range of reclaimed water irrigated produce estimated in comparable studies. We further discuss the desirability of HRW for irrigating home

Enhanced Harvesting of Chlorella vulgaris Using Combined Flocculants.

PubMed

Ma, Xiaochen; Zheng, Hongli; Zhou, Wenguang; Liu, Yuhuan; Chen, Paul; Ruan, Roger

2016-10-01

In this study, a novel flocculation strategy for harvesting Chlorella vulgaris with combined flocculants, poly (γ-glutamic acid) (γ-PGA) and calcium oxide (CaO), has been developed. The effect of flocculant dosage, the order of flocculant addition, mixing speed, and growth stage on the harvesting efficiency was evaluated. Results showed that the flocculation using combined flocculants significantly decreases the flocculant dosage and settling time compared with control. It was also found that CaO and γ-PGA influenced microalgal flocculation by changing the zeta potential of cells and pH of microalgal suspension. The most suitable order of flocculant addition was CaO first and then γ-PGA. The optimal mixing speed was 200 rpm for 0.5 min, followed by 50 rpm for another 4.5 min for CaO and γ-PGA with the highest flocculation efficiency of 95 % and a concentration factor of 35.5. The biomass concentration and lipid yield of the culture reusing the flocculated medium were similar to those when a fresh medium was used. Overall, the proposed method requires low energy input, alleviates biomass and water contamination, and reduces utilization of water resources and is feasible for harvesting C. vulgaris for biofuel and other bio-based chemical production.

Exploring methods to minimize the risk of mosquitoes in rainwater harvesting systems

NASA Astrophysics Data System (ADS)

Moglia, Magnus; Gan, Kein; Delbridge, Nathan

2016-12-01

Rainwater harvesting in residential homes is emerging as an important complement to centralized water supplies in urban centres around the world. Domestic rainwater harvesting systems provide a variety of benefits for water management and contribute to sustainable and integrated urban water management. There are however risks associated with rainwater harvesting that requires appropriate mitigation. One such risk is that systems can become breeding grounds for mosquitoes. This can constitute a significant health risk through the spread of mosquito-borne diseases (i.e. arbovirus and malaria). This paper explores the extent to which mosquitoes breed in rainwater harvesting systems as well as the effectiveness of different risk mitigation actions. Data were sourced from a large-scale domestic rainwater tank inspection survey undertaken in Melbourne and were analysed using simple Bayesian Network models. The observed rate of mosquito breeding was too high and was identified as a serious concern for health officials and water managers. The most common access routes into the tank system were found to be through the tank inlet or overflow. By exploring different system set-ups it was found that in order to mitigate the risk of mosquito breeding in tanks, all potential access routes must be adequately sealed. The complete eradication of mosquitos in rainwater tanks, however, may need further investigation, as 4% of systems with adequate protection at the inlet and overflow were still found to have mosquitoes in them.

Microbial source tracking in shellfish harvesting waters in the Gulf of Nicoya, Costa Rica.

PubMed

Symonds, E M; Young, S; Verbyla, M E; McQuaig-Ulrich, S M; Ross, E; Jiménez, J A; Harwood, V J; Breitbart, M

2017-03-15

Current microbial water quality monitoring is generally limited to culture-based measurements of fecal indicator bacteria (FIB). Given the many possible sources of fecal pollution within a watershed and extra-intestinal FIB reservoirs, it is important to determine source(s) of fecal pollution as a means to improve water quality and protect public health. The principal objective of this investigation was to characterize the microbial water quality of shellfish harvesting areas in the Gulf of Nicoya, Costa Rica during 2015. In order to achieve this objective, the specificity and sensitivity of 11 existing microbial source tracking (MST) PCR assays, associated with cows (BacCow), dogs (BacCan, DogBac), domestic wastewater (PMMoV), general avian (GFD), gulls (Gull2), horses (HorseBac, HoF), humans (HF183, HPyV), and pigs (PF), were evaluated using domestic wastewater and animal fecal samples collected from the region. The sensitivity of animal-associated assays ranged from 13 to 100%, while assay specificity ranged from 38 to 100%. The specificity of pepper mild mottle virus (PMMoV) and human polyomavirus (HPyV) was 100% for domestic wastewater, as compared to 94% specificity of the HF183 Bacteroidales marker. PMMoV was identified as a useful domestic wastewater-associated marker, with concentrations as high as 1.1 × 10 5 copies/ml and 100% sensitivity and specificity. Monthly surface water samples collected from four shellfish harvesting areas were analyzed using culture-based methods for Escherichia coli as well as molecular methods for FIB and a suite of MST markers, which were selected for their specificity in the region. While culturable E. coli results suggested possible fecal pollution during the monitoring period, the absence of human/domestic wastewater-associated markers and low FIB concentrations determined using molecular methods indicated sufficient microbial water quality for shellfish harvesting. This is the first study to our knowledge to test the

Design and engineering of water-soluble light-harvesting protein maquettes

DOE PAGES

Kodali, Goutham; Mancini, Joshua A.; Solomon, Lee A.; ...

2017-01-01

Natural selection in photosynthesis has engineered tetrapyrrole based, nanometer scale, light harvesting and energy capture in light-induced charge separation. By designing and creating nanometer scale artificial light harvesting and charge separating proteins, we have the opportunity to reengineer and overcome the limitations of natural selection to extend energy capture to new wavelengths and to tailor efficient systems that better meet human as opposed to cellular energetic needs. While tetrapyrrole cofactor incorporation in natural proteins is complex and often assisted by accessory proteins for cofactor transport and insertion, artificial protein functionalization relies on a practical understanding of the basic physical chemistrymore » of protein and cofactors that drive nanometer scale self-assembly. Patterning and balancing of hydrophobic and hydrophilic tetrapyrrole substituents is critical to avoid natural or synthetic porphyrin and chlorin aggregation in aqueous media and speed cofactor partitioning into the non-polar core of a man-made water soluble protein designed according to elementary first principles of protein folding. In conclusion, this partitioning is followed by site-specific anchoring of tetrapyrroles to histidine ligands strategically placed for design control of rates and efficiencies of light energy and electron transfer while orienting at least one polar group towards the aqueous phase.« less

Design and engineering of water-soluble light-harvesting protein maquettes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kodali, Goutham; Mancini, Joshua A.; Solomon, Lee A.

Natural selection in photosynthesis has engineered tetrapyrrole based, nanometer scale, light harvesting and energy capture in light-induced charge separation. By designing and creating nanometer scale artificial light harvesting and charge separating proteins, we have the opportunity to reengineer and overcome the limitations of natural selection to extend energy capture to new wavelengths and to tailor efficient systems that better meet human as opposed to cellular energetic needs. While tetrapyrrole cofactor incorporation in natural proteins is complex and often assisted by accessory proteins for cofactor transport and insertion, artificial protein functionalization relies on a practical understanding of the basic physical chemistrymore » of protein and cofactors that drive nanometer scale self-assembly. Patterning and balancing of hydrophobic and hydrophilic tetrapyrrole substituents is critical to avoid natural or synthetic porphyrin and chlorin aggregation in aqueous media and speed cofactor partitioning into the non-polar core of a man-made water soluble protein designed according to elementary first principles of protein folding. In conclusion, this partitioning is followed by site-specific anchoring of tetrapyrroles to histidine ligands strategically placed for design control of rates and efficiencies of light energy and electron transfer while orienting at least one polar group towards the aqueous phase.« less

25 CFR 163.12 - Harvesting restrictions.

Code of Federal Regulations, 2014 CFR

2014-04-01

... BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.12 Harvesting restrictions. (a) Harvesting timber on commercial forest land will not be permitted unless provisions for natural and/or artificial reforestation of acceptable tree...

Life cycle assessment of a commercial rainwater harvesting system compared with a municipal water supply system

EPA Science Inventory

Building upon previously published life cycle assessment (LCA) methodologies, we conducted an LCA of a commercial rainwater harvesting (RWH) system and compared it to a municipal water supply (MWS) system adapted to Washington, D.C. Eleven life cycle impact assessment (LCIA) indi...

Harvesting costs and environmental impacts associated with skyline yarding shelterwood harvests and thinning in Appalachian hardwoods

Treesearch

J. E. Baumgras; C. B. LeDoux; J. R. Sherar

1993-01-01

To evaluate the potential for moderating the visual impact and soil disturbance associated with timber harvesting on steep-slope hardwood sites, thinning and shelterwood harvests were conducted with a skyline yarding system. Operations were monitored to document harvesting production, residual stand damage, soil disturbance, and visual quality. Yarding costs for...

Harvesting systems and costs for short rotation poplar

Treesearch

B. Rummer; D. Mitchell

2013-01-01

The objective of this review is to compare the cost of coppice and longer rotation poplar harvesting technology. Harvesting technology for short rotation poplar has evolved over the years to address both coppice harvest and single-stem harvest systems. Two potential approaches for coppice harvesting are modified forage harvesters and modified mulcher-balers. Both of...

Is Corn Stover Harvest Predictable Using Farm Operation, Technology, and Management Variables?

USDA-ARS?s Scientific Manuscript database

Crop residue management, provision of animal feed or bedding, and increased income potential are some reasons for harvesting corn (Zea mays L.) stover. Reasons for not doing so are that crop residue is essential for restoring soil organic matter, protecting against wind and water erosion, and cyclin...

Refreshing Music: Fog Harvesting with Harps

NASA Astrophysics Data System (ADS)

Shi, Weiwei; Anderson, Mark; Kennedy, Brook; Boreyko, Jonathan

2017-11-01

Fog harvesting is a useful technique for obtaining fresh water in arid climates. The wire meshes currently utilized for fog harvesting suffer from dual constraints: coarse meshes cannot efficiently capture fog, while fine meshes suffer from clogging issues. Here, we design a new type of fog harvester comprised of an array of vertical wires, which we call ``fog harps.'' To investigate the water collection efficiency, three fog harps were designed with different diameters (254 μm, 508 μm and 1.30 mm) but the same pitch-to-diameter ratio of 2. For comparison, three different size meshes were purchased with equivalent dimensions. As expected for the mesh structures, the mid-sized wires performed the best, with a drop-off in performance for the fine or coarse meshes. In contrast, the fog harvesting rate continually increased with decreasing wire diameter for the fog harps, due to its low hysteresis that prevented droplet clogging. This resulted in a 3-fold enhancement in the fog harvesting rate for the harp form factor compared to the mesh. The lack of a performance ceiling for the harps suggest that even greater enhancements could be achieved by scaling down to yet smaller sizes.

Urban stormwater harvesting and reuse: a probe into the chemical, toxicology and microbiological contaminants in water quality.

PubMed

Chong, Meng Nan; Sidhu, Jatinder; Aryal, Rupak; Tang, Janet; Gernjak, Wolfgang; Escher, Beate; Toze, Simon

2013-08-01

Stormwater is one of the last major untapped urban water resources that can be exploited as an alternative water source in Australia. The information in the current Australian Guidelines for Water Recycling relating to stormwater harvesting and reuse only emphasises on a limited number of stormwater quality parameters. In order to supply stormwater as a source for higher value end-uses, a more comprehensive assessment on the potential public health risks has to be undertaken. Owing to the stochastic variations in rainfall, catchment hydrology and also the types of non-point pollution sources that can provide contaminants relating to different anthropogenic activities and catchment land uses, the characterisation of public health risks in stormwater is complex, tedious and not always possible through the conventional detection and analytical methods. In this study, a holistic approach was undertaken to assess the potential public health risks in urban stormwater samples from a medium-density residential catchment. A combined chemical-toxicological assessment was used to characterise the potential health risks arising from chemical contaminants, while a combination of standard culture methods and quantitative polymerase chain reaction (qPCR) methods was used for detection and quantification of faecal indicator bacteria (FIB) and pathogens in urban stormwater. Results showed that the concentration of chemical contaminants and associated toxicity were relatively low when benchmarked against other alternative water sources such as recycled wastewater. However, the concentrations of heavy metals particularly cadmium and lead have exceeded the Australian guideline values, indicating potential public health risks. Also, high numbers of FIB were detected in urban stormwater samples obtained from wet weather events. In addition, qPCR detection of human-related pathogens suggested there are frequent sewage ingressions into the urban stormwater runoff during wet weather events

The effects of surface wettability on the fog and dew moisture harvesting performance on tubular surfaces

PubMed Central

Seo, Donghyun; Lee, Junghun; Lee, Choongyeop; Nam, Youngsuk

2016-01-01

The efficient water harvesting from air-laden moisture has been a subject of great interest to address world-wide water shortage issues. Recently, it has been shown that tailoring surface wettability can enhance the moisture harvesting performance. However, depending on the harvesting condition, a different conclusion has often been reported and it remains unclear what type of surface wettability would be desirable for the efficient water harvesting under the given condition. Here we compare the water harvesting performance of the surfaces with various wettability under two different harvesting conditions–dewing and fogging, and show that the different harvesting efficiency of each surface under these two conditions can be understood by considering the relative importance of the water capturing and removal efficiency of the surface. At fogging, the moisture harvesting performance is determined by the water removal efficiency of the surface with the oil-infused surfaces exhibiting the best performance. Meanwhile, at dewing, both the water capturing and removal efficiency are crucial to the harvesting performance. And well-wetting surfaces with a lower barrier to nucleation of condensates exhibit a better harvesting performance due to the increasing importance of the water capture efficiency over the water removal efficiency at dewing. PMID:27063149

Monsoon Harvests: Assessing the Impact of Rainwater Harvesting Ponds on Subsistence-Level Agriculture in the Gundar Basin, Tamil Nadu, India

NASA Astrophysics Data System (ADS)

Steiff, M.; Van Meter, K. J.; Basu, N. B.

2013-12-01

Lack of consistent water availability for irrigated agriculture is recognized as one of the primary constraints to meeting the UN Millennium Development Goals to alleviate hunger, and in semi-arid landscapes such as those of southern India, which are characterized by high intra-annual variability in rainfall, provision of capabilities for seasonal storage is recognized to be one of the key strategies towards alleviating water scarcity problems and ensuring food security. Although the issue of increased storage can be addressed by centralized infrastructure projects such as large-scale irrigation systems and dams, an alternative is the "soft path" approach, in which existing large-scale projects are complemented by small-scale, decentralized solutions. Such a decentralized approach has been utilized in southern India for thousands of years in the form of village rainwater harvesting tanks or ponds, providing a local and inherently sustainable approach to providing sufficient water for rice cultivation. Over the last century, however, large-scale canal projects and groundwater pumping have replaced rainwater harvesting as the primary source of irrigation water. But with groundwater withdrawals now exceeding recharge in many areas and water tables continuing to drop, many NGOs and government agencies are advocating for a revival of the older rainwater harvesting systems. Questions remain, however, regarding the limits to which rainwater harvesting can provide a solution to decades of water overexploitation. In the present work, we have utilized secondary data sources to analyze the linkages between the tank irrigation systems and the village communities that depend on them within the Gundar Basin of southern Tamil Nadu. Combining socioeconomic data with information regarding climate, land use, groundwater depletion, and tank density, we have developed indicators of sustainability for these systems. Using these indicators, we have attempted to unravel the close

Maintaining antioxidant potential of fresh fruits and vegetables after harvest.

PubMed

Villa-Rodriguez, Jose A; Palafox-Carlos, H; Yahia, Elhadi M; Ayala-Zavala, J Fernando; Gonzalez-Aguilar, Gustavo A

2015-01-01

The consumption of fruits and vegetables has increased in the past few years, not only because of their attractive sensorial properties, but also for their nutritional and health benefits. Antioxidants are compounds found in fresh fruits and vegetables, and evidence of their role in the prevention of degenerative diseases is continuously emerging. However, the antioxidants in some fruits and vegetables can be lost during handling after harvest, even during minimal processing and storage. In this sense, postharvest treatments are needed to preserve the quality and antioxidant potential of fresh produce. Postharvest treatments and technologic strategies (including ultraviolet light, controlled and modified atmospheres, heat treatments, and application of natural compounds, such as edible coatings, active packaging, microencapsulation, and nanoemulsion) have shown positive and promising results to maintain fruit and vegetable antioxidant potential. The purpose of this review is to analyze and propose the application of postharvest strategies to maintain, or even improve, the antioxidant status of fruits and vegetables, thus offering options to maximize health benefits to consumers.

Conservation of water for washing beef heads at harvest.

PubMed

DeOtte, R E; Spivey, K S; Galloway, H O; Lawrence, T E

2010-03-01

The objective of this research was to develop methods to conserve water necessary to cleanse beef heads prior to USDA-FSIS inspection. This was to be accomplished by establishing a baseline for the minimum amount of water necessary to adequately wash a head and application of image analysis to provide an objective measure of head cleaning. Twenty-one beef heads were manually washed during the harvest process. An average 18.75 L (2.49 SD) and a maximum of 23.88 L were required to cleanse the heads to USDA-FSIS standards. Digital images were captured before and after manual washing then evaluated for percentage red saturation using commercially available image analysis software. A decaying exponential curve extracted from these data indicated that as wash water increased beyond 20 L the impact on red saturation decreased. At 4 sigma from the mean of 18.75 L, red saturation is 16.0 percent, at which logistic regression analysis indicates 99.994 percent of heads would be accepted for inspection, or less than 1 head in 15,000 would be rejected. Reducing to 3 sigma would increase red saturation to 27.6 percent, for which 99.730 percent of heads likely would be accepted (less than 1 in 370 would be rejected). Copyright 2009 Elsevier Ltd. All rights reserved.

The urban harvest approach as framework and planning tool for improved water and resource cycles.

PubMed

Leusbrock, I; Nanninga, T A; Lieberg, K; Agudelo-Vera, C M; Keesman, K J; Zeeman, G; Rijnaarts, H H M

2015-01-01

Water and resource availability in sufficient quantity and quality for anthropogenic needs represents one of the main challenges in the coming decades. To prepare for upcoming challenges such as increased urbanization and climate change related consequences, innovative and improved resource management concepts are indispensable. In recent years we have developed and applied the urban harvest approach (UHA). The UHA aims to model and quantify the urban water cycle on different temporal and spatial scales. This approach allowed us to quantify the impact of the implementation of water saving measures and new water treatment concepts in cities. In this paper we will introduce the UHA and its application for urban water cycles. Furthermore, we will show first results for an extension to energy cycles and highlight future research items (e.g. nutrients, water-energy-nexus).

The potential of the tree water potential.

PubMed

Steppe, Kathy

2018-06-12

Non-invasive quantification of tree water potential is one of the grand challenges for assessing the fate of trees and forests in the coming decades. Tree water potential is a robust and direct indicator of tree water status and is preferably used to track how trees, forests and vegetation in general respond to changes in climate and drought. In this issue of Tree Physiology, Dietrich et al. (2018) predict the daily canopy water potential of mature temperate trees from tree water deficit derived from stem diameter variation measurements.

The effects of harvest on waterfowl populations

USGS Publications Warehouse

Cooch, Evan G.; Guillemain, Matthieu; Boomer, G Scott; Lebreton, Jean-Dominique; Nichols, James D.

2014-01-01

Overall, there is substantial uncertainty about system dynamics, about the impacts of potential management and conservation decisions on those dynamics, and how to optimise management decisions in the presence of such uncertainties. Such relationships are unlikely to be stationary over space or time, and selective harvest of some individuals can potentially alter life history allocation of resources over time – both of which will potentially influence optimal harvest strategies. These sources of variation and uncertainty argue for the use of adaptive approaches to waterfowl harvest management.

Approaches to automated protein crystal harvesting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deller, Marc C., E-mail: mdeller@scripps.edu; Rupp, Bernhard, E-mail: mdeller@scripps.edu

Approaches to automated and robot-assisted harvesting of protein crystals are critically reviewed. While no true turn-key solutions for automation of protein crystal harvesting are currently available, systems incorporating advanced robotics and micro-electromechanical systems represent exciting developments with the potential to revolutionize the way in which protein crystals are harvested.

Ethephon As a Potential Abscission Agent for Table Grapes: Effects on Pre-Harvest Abscission, Fruit Quality, and Residue

PubMed Central

Ferrara, Giuseppe; Mazzeo, Andrea; Matarrese, Angela M. S.; Pacucci, Carmela; Trani, Antonio; Fidelibus, Matthew W.; Gambacorta, Giuseppe

2016-01-01

Some plant growth regulators, including ethephon, can stimulate abscission of mature grape berries. The stimulation of grape berry abscission reduces fruit detachment force (FDF) and promotes the development of a dry stem scar, both of which could facilitate the production of high quality stemless fresh-cut table grapes. The objective of this research was to determine how two potential abscission treatments, 1445 and 2890 mg/L ethephon, affected FDF, pre-harvest abscission, fruit quality, and ethephon residue of Thompson Seedless and Crimson Seedless grapes. Both ethephon treatments strongly induced abscission of Thompson Seedless berries causing >90% pre-harvest abscission. Lower ethephon rates, a shorter post-harvest interval, or berry retention systems such as nets, would be needed to prevent excessive pre-harvest losses. The treatments also slightly affected Thompson Seedless berry skin color, with treated fruit being darker, less uniform in color, and with a more yellow hue than non-treated fruit. Ethephon residues on Thompson Seedless grapes treated with the lower concentration of ethephon were below legal limits at harvest. Ethephon treatments also promoted abscission of Crimson Seedless berries, but pre-harvest abscission was much lower (≅49%) in Crimson Seedless compared to Thompson Seedless. Treated fruits were slightly darker than non-treated fruits, but ethephon did not affect SSC, acidity, or firmness of Crimson Seedless, and ethephon residues were below legal limits. PMID:27303407

The effect of roofing material on the quality of harvested rainwater.

PubMed

Mendez, Carolina B; Klenzendorf, J Brandon; Afshar, Brigit R; Simmons, Mark T; Barrett, Michael E; Kinney, Kerry A; Kirisits, Mary Jo

2011-02-01

Due to decreases in the availability and quality of traditional water resources, harvested rainwater is increasingly used for potable and non-potable purposes. In this study, we examined the effect of conventional roofing materials (i.e., asphalt fiberglass shingle, Galvalume(®) metal, and concrete tile) and alternative roofing materials (i.e., cool and green) on the quality of harvested rainwater. Results from pilot-scale and full-scale roofs demonstrated that rainwater harvested from any of these roofing materials would require treatment if the consumer wanted to meet United States Environmental Protection Agency primary and secondary drinking water standards or non-potable water reuse guidelines; at a minimum, first-flush diversion, filtration, and disinfection are recommended. Metal roofs are commonly recommended for rainwater harvesting applications, and this study showed that rainwater harvested from metal roofs tends to have lower concentrations of fecal indicator bacteria as compared to other roofing materials. However, concrete tile and cool roofs produced harvested rainwater quality similar to that from the metal roofs, indicating that these roofing materials also are suitable for rainwater harvesting applications. Although the shingle and green roofs produced water quality comparable in many respects to that from the other roofing materials, their dissolved organic carbon concentrations were very high (approximately one order of magnitude higher than what is typical for a finished drinking water in the United States), which might lead to high concentrations of disinfection byproducts after chlorination. Furthermore the concentrations of some metals (e.g., arsenic) in rainwater harvested from the green roof suggest that the quality of commercial growing media should be carefully examined if the harvested rainwater is being considered for domestic use. Hence, roofing material is an important consideration when designing a rainwater catchment. Copyright �

Effects of timber harvesting on the genetic potential for carbon and nitrogen cycling in five North American forest ecozones.

PubMed

Cardenas, Erick; Orellana, Luis H; Konstantinidis, Konstantinos T; Mohn, William W

2018-02-16

Forest ecosystems are critical to global biogeochemical cycles but under pressure from harvesting and climate change. We investigated the effects of organic matter (OM) removal during forest harvesting on the genetic potential of soil communities for biomass decomposition and nitrogen cycling in five ecozones across North America. We analyzed 107 samples, representing four treatments with varied levels of OM removal, at Long-Term Soil Productivity Study sites. Samples were collected more than ten years after harvesting and replanting and were analyzed via shotgun metagenomics. High-quality short reads totaling 1.2 Tbp were compared to the Carbohydrate Active Enzyme (CAZy) database and a custom database of nitrogen cycle genes. Gene profile variation was mostly explained by ecozone and soil layer. Eleven CAZy and nine nitrogen cycle gene families were associated with particular soil layers across all ecozones. Treatment effects on gene profiles were mainly due to harvesting, and only rarely to the extent of OM removal. Harvesting generally decreased the relative abundance of CAZy genes while increasing that of nitrogen cycle genes, although these effects varied among ecozones. Our results suggest that ecozone-specific nutrient availability modulates the sensitivity of the carbon and nitrogen cycles to harvesting with possible consequences for long-term forest sustainability.

Dry creek long-term watershed study: effects of timber harvest on hydrology and sediment export in headwater streams in Southwest Georgia

Treesearch

W.B. Summer; C. Rhett Jackson; D. Jones; M. Miwa

2006-01-01

Properly established streamside management zones (SMZs) reduce potential impacts of timber harvesting on stream hydro-period and sediment fluxes. Effects of upland silvicultural practices on stream hydrology and effects of partial harvesting within SMZs on water quality are not well documented. The objectives of this study are to determine the effects of these forest...

Evaluation of stormwater harvesting sites using multi criteria decision methodology

NASA Astrophysics Data System (ADS)

Inamdar, P. M.; Sharma, A. K.; Cook, Stephen; Perera, B. J. C.

2018-07-01

Selection of suitable urban stormwater harvesting sites and associated project planning are often complex due to spatial, temporal, economic, environmental and social factors, and related various other variables. This paper is aimed at developing a comprehensive methodology framework for evaluating of stormwater harvesting sites in urban areas using Multi Criteria Decision Analysis (MCDA). At the first phase, framework selects potential stormwater harvesting (SWH) sites using spatial characteristics in a GIS environment. In second phase, MCDA methodology is used for evaluating and ranking of SWH sites in multi-objective and multi-stakeholder environment. The paper briefly describes first phase of framework and focuses chiefly on the second phase of framework. The application of the methodology is also demonstrated over a case study comprising of the local government area, City of Melbourne (CoM), Australia for the benefit of wider water professionals engaged in this area. Nine performance measures (PMs) were identified to characterise the objectives and system performance related to the eight alternative SWH sites for the demonstration of the application of developed methodology. To reflect the stakeholder interests in the current study, four stakeholder participant groups were identified, namely, water authorities (WA), academics (AC), consultants (CS), and councils (CL). The decision analysis methodology broadly consisted of deriving PROMETHEE II rankings of eight alternative SWH sites in the CoM case study, under two distinct group decision making scenarios. The major innovation of this work is the development and application of comprehensive methodology framework that assists in the selection of potential sites for SWH, and facilitates the ranking in multi-objective and multi-stakeholder environment. It is expected that the proposed methodology will assist the water professionals and managers with better knowledge that will reduce the subjectivity in the

50 CFR 622.383 - Limited harvest species.

Code of Federal Regulations, 2013 CFR

2013-10-01

... ADMINISTRATION, DEPARTMENT OF COMMERCE FISHERIES OF THE CARIBBEAN, GULF OF MEXICO, AND SOUTH ATLANTIC Coastal Migratory Pelagic Resources (Gulf of Mexico and South Atlantic) § 622.383 Limited harvest species. (a... applicable to state waters. A species subject to a harvest limitation specified in this section taken in the...

50 CFR 622.383 - Limited harvest species.

Code of Federal Regulations, 2014 CFR

2014-10-01

... ADMINISTRATION, DEPARTMENT OF COMMERCE FISHERIES OF THE CARIBBEAN, GULF OF MEXICO, AND SOUTH ATLANTIC Coastal Migratory Pelagic Resources (Gulf of Mexico and South Atlantic) § 622.383 Limited harvest species. (a... applicable to state waters. A species subject to a harvest limitation specified in this section taken in the...

Effects of timber harvest on water quantity and quality in small watersheds in the Piedmont of North Carolina

Treesearch

Johnny Boggs; Ge Sun; Steven McNulty

2015-01-01

This paired watershed study tested the effects of timber harvest on water quantity and quality in the North Carolina Piedmont physiographic region. Four headwater watersheds at Hill Demonstration Forest (HF1, HF2, HFW1, and HFW2) and two at Umstead Research Farm (UF1 and UF2) were continuously monitored for discharge and water quality from 2007 to 2013. The HF1 and UF1...

Design of runoff water harvesting systems and its role in minimizing water losses

NASA Astrophysics Data System (ADS)

Berliner, P.; Carmi, G.; Leake, S.; Agam, N.

2016-12-01

Precipitation is one of the major water sources for agricultural production in arid and semi-arid areas. Rainfalls are limited, erratic and not always coincide with the crop growing season. Only a part of the rain is absorbed by the soil. Soil evaporation is most severe in these regions and the large part of the absorbed water is lost to evaporation. The technique of collecting and conveying the runoff is known as runoff harvesting. Microcatchments are one of the primary techniques used for collecting, storing and conserving local surface runoff for growing trees/shrubs. In this system, runoff water is collected close-by the area in which it was generated, and trees/shrubs may utilize the water. The main objective of the present research was to estimate the effect of the design of the micro-catchment collection area (shallow basin and deep trench) has on the efficiency of the water conservation in the soil profile. The study was carried out during two years using regular micro-catchments (three replicates) with a surface area of 9 m2 (3 x 3 m) and a depth of 0.1 m and trenches (three replicates) with a surface area of 12 m2 (12 x 1 m) and 1 m depth. One and three olive trees were planted inside the trenches and micro-catchments, respectively. Access tubes for neutron probe were installed in micro-catchments and trenches (four and seven, respectively) to depths of 3m. Soil water content in the soil profile was monitored. Sap flow in trees was measured by PS-TDP8 Granier sap flow system every 0.5 hour and fluxes computed for the time intervals that correspond to the soil water measurements. The first year study included flooding trenches and regular micro-catchments once with the same amount of water (1.5 m3) and the second year study included flooding four times with 0.25 m3 each time. Flooding was followed by monitoring the water balance components and estimation of evaporation losses and water use efficiency by olive trees. Evaporation from trenches and regular

Improving the water use efficiency of olive trees growing in water harvesting systems

NASA Astrophysics Data System (ADS)

Berliner, Pedro; Leake, Salomon; Carmi, Gennady; Agam, Nurit

2017-04-01

content between two consecutive measurements and transpiration for this interval estimated from sap flow measurements. In both years the evaporation from micro-catchments was significantly larger than that of trenches. The fractional loss due to evaporation from the total applied water for the second year for example, was 53% and 22% for micro-catchments and trenches, respectively. This indicates that a trench geometry reduces the amount of water lost to direct evaporation from the soil, and is thus more efficient in utilizing harvested runoff water.

How much drinking water can be saved by using rainwater harvesting on a large urban area? application to Paris agglomeration.

PubMed

Belmeziti, Ali; Coutard, Olivier; de Gouvello, Bernard

2014-01-01

This paper is based on a prospective scenario of development of rainwater harvesting (RWH) on a given large urban area (such as metropolitan area or region). In such a perspective, a new method is proposed to quantify the related potential of potable water savings (PPWS) indicator on this type of area by adapting the reference model usually used on the building level. The method is based on four setting-up principles: gathering (definition of buildings-types and municipalities-types), progressing (use of an intermediate level), increasing (choice of an upper estimation) and prioritizing (ranking the stakes of RWH). Its application to the Paris agglomeration shows that is possible to save up to 11% of the total current potable water through the use of RWH. It also shows that the residential sector offers the most important part because it holds two-thirds of the agglomeration PPWS.

Impacts of Combined Cooling, Heating and Power Systems, and Rainwater Harvesting on Water Demand, Carbon Dioxide, and NOx Emissions for Atlanta.

PubMed

James, Jean-Ann; Sung, Sangwoo; Jeong, Hyunju; Broesicke, Osvaldo A; French, Steven P; Li, Duo; Crittenden, John C

2018-01-02

The purpose of this study is to explore the potential water, CO 2 and NO x emission, and cost savings that the deployment of decentralized water and energy technologies within two urban growth scenarios can achieve. We assess the effectiveness of urban growth, technological, and political strategies to reduce these burdens in the 13-county Atlanta metropolitan region. The urban growth between 2005 and 2030 was modeled for a business as usual (BAU) scenario and a more compact growth (MCG) scenario. We considered combined cooling, heating and power (CCHP) systems using microturbines for our decentralized energy technology and rooftop rainwater harvesting and low flow fixtures for the decentralized water technologies. Decentralized water and energy technologies had more of an impact in reducing the CO 2 and NO x emissions and water withdrawal and consumption than an MCG growth scenario (which does not consider energy for transit). Decentralized energy can reduce the CO 2 and NO x emissions by 8% and 63%, respectively. Decentralized energy and water technologies can reduce the water withdrawal and consumption in the MCG scenario by 49% and 50% respectively. Installing CCHP systems on both the existing and new building stocks with a net metering policy could reduce the CO 2 , NO x , and water consumption by 50%, 90%, and 75% respectively.

Rainwater harvesting and management in rainfed agricultural systems in sub-Saharan Africa - A review

NASA Astrophysics Data System (ADS)

Biazin, Birhanu; Sterk, Geert; Temesgen, Melesse; Abdulkedir, Abdu; Stroosnijder, Leo

Agricultural water scarcity in the predominantly rainfed agricultural system of sub-Saharan Africa (SSA) is more related to the variability of rainfall and excessive non-productive losses, than the total annual precipitation in the growing season. Less than 15% of the terrestrial precipitation takes the form of productive ‘green’ transpiration. Hence, rainwater harvesting and management (RWHM) technologies hold a significant potential for improving rainwater-use efficiency and sustaining rainfed agriculture in the region. This paper outlines the various RWHM techniques being practiced in SSA, and reviews recent research results on the performance of selected practices. So far, micro-catchment and in situ rainwater harvesting techniques are more common than rainwater irrigation techniques from macro-catchment systems. Depending on rainfall patterns and local soil characteristics, appropriate application of in situ and micro-catchment techniques could improve the soil water content of the rooting zone by up to 30%. Up to sixfold crop yields have been obtained through combinations of rainwater harvesting and fertiliser use, as compared to traditional practices. Supplemental irrigation of rainfed agriculture through rainwater harvesting not only reduces the risk of total crop failure due to dry spells, but also substantially improves water and crop productivity. Depending on the type of crop and the seasonal rainfall pattern, the application of RWHM techniques makes net profits more possible, compared to the meagre profit or net loss of existing systems. Implementation of rainwater harvesting may allow cereal-based smallholder farmers to shift to diversified crops, hence improving household food security, dietary status, and economic return. The much needed green revolution and adaptations to climate change in SSA should blend rainwater harvesting ideals with agronomic principles. More efforts are needed to improve the indigenous practices, and to disseminate best

"Straight from the heavens into your bucket": domestic rainwater harvesting as a measure to improve water security in a subarctic indigenous community.

PubMed

Mercer, Nicholas; Hanrahan, Maura

2017-01-01

Black Tickle-Domino is an extremely water-insecure remote Inuit community in the Canadian subarctic that lacks piped-water. Drinking water consumption in the community is less than a third of the Canadian national average. Water insecurity in the community contributes to adverse health, economic, and social effects and requires urgent action. To test the ability of domestic rainwater harvesting (DRWH) for the first time in the subarctic with the goal of improving water access and use in the community. This project utilised quantitative weekly reporting of water collection and use, as well as focus group discussions. DRWH units were installed at seven water-insecure households chosen by the local government. Results were measured over a 6-week period in 2016. Participants harvested 19.07 gallons of rainwater per week. General purpose water consumption increased by 17% and water retrieval efforts declined by 40.92%. Households saved $12.70 CDN per week. Participants reported perceived improvements to psychological health. Because no potable water was collected, drinking water consumption did not increase. The study identified additional water-insecurity impacts. DRWH cannot supply drinking water without proper treatment and filtration; however, it can be a partial remedy to water insecurity in the subarctic. DRWH is appropriately scaled, inexpensive, and participants identified several significant benefits.

Hetero-type dual photoanodes for unbiased solar water splitting with extended light harvesting

PubMed Central

Kim, Jin Hyun; Jang, Ji-Wook; Jo, Yim Hyun; Abdi, Fatwa F.; Lee, Young Hye; van de Krol, Roel; Lee, Jae Sung

2016-01-01

Metal oxide semiconductors are promising photoelectrode materials for solar water splitting due to their robustness in aqueous solutions and low cost. Yet, their solar-to-hydrogen conversion efficiencies are still not high enough for practical applications. Here we present a strategy to enhance the efficiency of metal oxides, hetero-type dual photoelectrodes, in which two photoanodes of different bandgaps are connected in parallel for extended light harvesting. Thus, a photoelectrochemical device made of modified BiVO4 and α-Fe2O3 as dual photoanodes utilizes visible light up to 610 nm for water splitting, and shows stable photocurrents of 7.0±0.2 mA cm−2 at 1.23 VRHE under 1 sun irradiation. A tandem cell composed with the dual photoanodes–silicon solar cell demonstrates unbiased water splitting efficiency of 7.7%. These results and concept represent a significant step forward en route to the goal of >10% efficiency required for practical solar hydrogen production. PMID:27966548

Hetero-type dual photoanodes for unbiased solar water splitting with extended light harvesting.

PubMed

Kim, Jin Hyun; Jang, Ji-Wook; Jo, Yim Hyun; Abdi, Fatwa F; Lee, Young Hye; van de Krol, Roel; Lee, Jae Sung

2016-12-14

Metal oxide semiconductors are promising photoelectrode materials for solar water splitting due to their robustness in aqueous solutions and low cost. Yet, their solar-to-hydrogen conversion efficiencies are still not high enough for practical applications. Here we present a strategy to enhance the efficiency of metal oxides, hetero-type dual photoelectrodes, in which two photoanodes of different bandgaps are connected in parallel for extended light harvesting. Thus, a photoelectrochemical device made of modified BiVO 4 and α-Fe 2 O 3 as dual photoanodes utilizes visible light up to 610 nm for water splitting, and shows stable photocurrents of 7.0±0.2 mA cm -2 at 1.23 V RHE under 1 sun irradiation. A tandem cell composed with the dual photoanodes-silicon solar cell demonstrates unbiased water splitting efficiency of 7.7%. These results and concept represent a significant step forward en route to the goal of >10% efficiency required for practical solar hydrogen production.

Nonlinear Interactions for Broadband Energy Harvesting

DTIC Science & Technology

2015-04-22

harvesting ,” Journal of Sound and Vibration , V. 331, No. 4, pp. 922– 937. 12. Sah, S.M., Mann, B.P., 2012, “Potential well metamorphosis of a pivoting...Nonlinear non- conservative behavior and modeling of piezoelectric energy harvesters including proof mass effects,” Journal of Intelligent Material...Experimental investigation of a post-buckled piezoelectric beam with an attached central mass used to harvest energy,” Journal of Sys- tems and Control

Acceptability of the rainwater harvesting system to the slum dwellers of Dhaka City.

PubMed

Islam, M M; Chou, F N-F; Kabir, M R

2010-01-01

Urban area like Dhaka City, in Bangladesh, has scarcity of safe drinking water which is one of the prominent basic needs for human kind. This study explored the acceptability of harvested rainwater in a densely populated city like Dhaka, using a simple and low cost technology. A total of 200 random people from four slums of water-scarce Dhaka City were surveyed to determine the dwellers' perception on rainwater and its acceptability as a source of drinking water. The questionnaire was aimed at finding the socio-economic condition and the information on family housing, sanitation, health, existing water supply condition, knowledge about rainwater, willingness to accept rainwater as a drinking source etc. A Yield before Spillage (YBS) model was developed to know the actual rainwater availability and storage conditions which were used to justify the effective tank size. Cost-benefit analysis and feasibility analysis were performed using the survey results and the research findings. The survey result and overall study found that the low cost rainwater harvesting technique was acceptable to the slum dwellers as only the potential alternative source of safe drinking water.

Veg-01 Plant Harvest

NASA Image and Video Library

2014-06-10

Commander Steve Swanson harvests plants for the VEG-01 investigation. He is harvesting them on the Maintenance Work Area (MWA) in the Node 2/Harmony. The Veg-01 hardware validation test investigation utilizes the Veggie facility on ISS. This investigation will assess on-orbit function and performance of the Veggie,and focus on the growth and development of Outredgeous Lettuce (Lactuca sativa ) seedlings in the spaceflight environment and the effects of the spaceflight environment on composition of microbial flora on the Veggie-grown plants and the Veggie facility. Lettuce plants are harvested on-orbit, frozen at <-80oC and returned to the ground for post-flight evaluation. Microbial sampling swabs will be taken of the Veggie facility and plant material, frozen and returned to the ground for environmental microbiological examination. Rooting pillows and water sample syringes will also be returned for microbial sampling and root analysis.

A Review of Roof Harvested Rainwater in Australia

PubMed Central

Whiley, Harriet; Edwards, John W.; Ross, Kirstin E.

2018-01-01

To address concern regarding water sustainability, the Australian Federal Government and many state governments have implemented regulatory mechanisms and incentives to support households to purchase and install rainwater harvesting systems. This has led to an increase in rainwater harvesting in regional and urban Australia. This review examines the implementation of the regulatory mechanisms across Australia. In addition, the literature investigating the potential health consequences of rainwater consumption in Australia was explored. Studies demonstrated that although trace metals such as arsenic, cadmium, chromium, lead, and iron were present in Australian rainwater, these metallic elements were generally found below the health limit guideline, except in high industrial areas. In addition, pathogenic or indicator microorganisms that include, but are not limited to, Escherichia coli, total and faecal coliforms, Campylobacter, Salmonella, Legionella, Pseudomonas, Cryptosporidium, Enterococci, Giardia, Aeromonas, and Mycobacterium avium Complex (MAC) have been detected in rainwater collected in Australia. However, epidemiological evidence suggests that drinking rainwater does not increase the risk of gastrointestinal disease. It was also identified that there is a need for further research investigating the potential for rainwater to be a source of infection for opportunistic pathogens. PMID:29606962

[Effects of ridge and furrow rain harvesting with supplemental irrigation on winter wheat photosynthetic characteristics, yield and water use efficiency in Guanzhong irrigation district].

PubMed

Zhang, Yu; Han, Qing-fang; Cheng, Xue-feng; Yang, Shan-shan; Jia, Zhi-kuan; Ding, Rui-xia; Ren, Xiao-long; Nie, Jun-feng

2015-05-01

A field experiment was conducted to determine the regulation of crop photosynthesis and output and water saving effect under ridge and furrow rain harvesting with supplemental irrigation in Guanzhong irrigation district. The experiment was set with 5 treatments with irrigation at returning green stage, and the widths of both ridge and furrow being 60 cm. T1, T2 and T3 were in the ridge and furrow rain harvesting planting pattern, with the irrigation volumes being 0, 375 and 750 m3 · hm(-2) respectively, T4 was flat planting with irrigation (border irrigation) of 750 m3 · hm(-2) and CK was flat planting without irrigation. Effects on winter wheat photosynthetic organs, photosynthetic rate, yield and water use efficiency, etc. were tested. The results showed that compared with T4, T1, T2 and T3 treatments increased the grain yield by 2.8%, 9.6% and 18.9%, improved the harvest index by 2.0% to 8.5%, advanced the flag leaf chlorophyll content by 41.9% to 64.4% significantly, and improved the 0-40 cm layer soil moisture content by 0.1%-4.6% during the whole growth period. Photosynthetic rates at the flowering and filling stages also increased by 22.3% to 54.2% and -4.3% to 67.2%, respectively. Total water use efficiencies (WUEy) were 17.9%, 10.4% and 15.4% higher than that of T4, and 69.3%, 58.6% and 65.7% higher than that of CK (P < 0.05), respectively, and enhanced precipitation utilization efficiency ( PUE ) by 94.3%-124.5% than CK. Leaf areas of T2 and T3 treatments at each growth stage were significantly higher than that of T4 and CK, irrigation water use efficiencies (IUE) were 119.1% and 18.8% higher than that of T4, respectively. Therefore, it was concluded that ridge and furrow rain harvesting cultivation could maintain higher grain yield than border irrigation without irrigation or with irrigation reduction by 50%. The utilization efficiency of irrigation water under the condition of irrigation reduction by 50% was improved significantly, and the ridge and

A nanowire based triboelectric nanogenerator for harvesting water wave energy and its applications

NASA Astrophysics Data System (ADS)

Li, Xiaoyi; Tao, Juan; Zhu, Jing; Pan, Caofeng

2017-07-01

The ocean wave energy is one of the most promising renewable and clean energy sources for human life, which is the so-called "Blue energy." In this work, a nanowire based triboelectric nanogenerator was designed for harvesting wave energy. The nanowires on the surface of FEP largely raise the contacting area with water and also make the polymer film hydrophobic. The output can reach 10 μ A and 200 V. When combined with a capacitor, an infrared emitter, and a receiver, a self-powered wireless infrared system is fabricated, which can be used in the fields of communication and detecting.

Electrochemically driven mechanical energy harvesting.

PubMed

Kim, Sangtae; Choi, Soon Ju; Zhao, Kejie; Yang, Hui; Gobbi, Giorgia; Zhang, Sulin; Li, Ju

2016-01-06

Efficient mechanical energy harvesters enable various wearable devices and auxiliary energy supply. Here we report a novel class of mechanical energy harvesters via stress-voltage coupling in electrochemically alloyed electrodes. The device consists of two identical Li-alloyed Si as electrodes, separated by electrolyte-soaked polymer membranes. Bending-induced asymmetric stresses generate chemical potential difference, driving lithium ion flux from the compressed to the tensed electrode to generate electrical current. Removing the bending reverses ion flux and electrical current. Our thermodynamic analysis reveals that the ideal energy-harvesting efficiency of this device is dictated by the Poisson's ratio of the electrodes. For the thin-film-based energy harvester used in this study, the device has achieved a generating capacity of 15%. The device demonstrates a practical use of stress-composition-voltage coupling in electrochemically active alloys to harvest low-grade mechanical energies from various low-frequency motions, such as everyday human activities.

Electrochemically driven mechanical energy harvesting

PubMed Central

Kim, Sangtae; Choi, Soon Ju; Zhao, Kejie; Yang, Hui; Gobbi, Giorgia; Zhang, Sulin; Li, Ju

2016-01-01

Efficient mechanical energy harvesters enable various wearable devices and auxiliary energy supply. Here we report a novel class of mechanical energy harvesters via stress–voltage coupling in electrochemically alloyed electrodes. The device consists of two identical Li-alloyed Si as electrodes, separated by electrolyte-soaked polymer membranes. Bending-induced asymmetric stresses generate chemical potential difference, driving lithium ion flux from the compressed to the tensed electrode to generate electrical current. Removing the bending reverses ion flux and electrical current. Our thermodynamic analysis reveals that the ideal energy-harvesting efficiency of this device is dictated by the Poisson's ratio of the electrodes. For the thin-film-based energy harvester used in this study, the device has achieved a generating capacity of 15%. The device demonstrates a practical use of stress-composition–voltage coupling in electrochemically active alloys to harvest low-grade mechanical energies from various low-frequency motions, such as everyday human activities. PMID:26733282

Phytoremediation of arsenic-contaminated groundwater using arsenic hyperaccumulator Pteris vittata L.: effects of frond harvesting regimes and arsenic levels in refill water.

PubMed

Natarajan, Seenivasan; Stamps, Robert H; Ma, Lena Q; Saha, Uttam K; Hernandez, Damaris; Cai, Yong; Zillioux, Edward J

2011-01-30

A large-scale hydroponic system to phytoremediate arsenic-contaminated groundwater using Pteris vittata (Chinese brake fern) was successfully tested in a field. In this 30-wk study, three frond-harvesting regimes (all, mature, and senescing fronds) and two water-refilling schemes to compensate for evapotranspiration (high-As water of 140-180 μg/L and low-As water of <7 μg/L) were investigated. Two experiments (Cycle 1 and Cycle 2) were conducted using the same plants in 24 tanks with each containing 600 L of arsenic-contaminated groundwater and 32 ferns. During Cycle 1 and with initial As of 140 μg/L, As in tanks refilled with low-As water was reduced to <10 μg/L in 8 wks compared to <10 μg/L in 17 wks in tanks refilled with high-As water. During Cycle 2 and with initial As of 180 μg/L, the remediation time was reduced by 2-5 wks, indicating that more established ferns were more efficient. In areas where clean water is limiting, refilling high-As water coupled with harvesting senescing fronds is recommended for more effective As phytoremediation. Published by Elsevier B.V.

50 CFR 300.132 - Lobster harvest limitations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... harvest limitations. (a) Berried lobsters. A berried (egg-bearing) lobster in treaty waters may not be retained on board. A berried lobster must be returned immediately to the water unharmed. A berried lobster... lobster smaller than the minimum size limit must be returned immediately to the water unharmed. ...

Critical evaluation and modeling of algal harvesting using dissolved air flotation. DAF Algal Harvesting Modeling

DOE PAGES

Zhang, Xuezhi; Hewson, John C.; Amendola, Pasquale; ...

2014-07-14

In our study, Chlorella zofingiensis harvesting by dissolved air flotation (DAF) was critically evaluated with regard to algal concentration, culture conditions, type and dosage of coagulants, and recycle ratio. Harvesting efficiency increased with coagulant dosage and leveled off at 81%, 86%, 91%, and 87% when chitosan, Al 3+, Fe 3+, and cetyl trimethylammonium bromide (CTAB) were used at dosages of 70, 180, 250, and 500 mg g -1, respectively. The DAF efficiency-coagulant dosage relationship changed with algal culture conditions. In evaluating the influence of the initial algal concentration and recycle ratio revealed that, under conditions typical for algal harvesting, wemore » found that it is possible that the number of bubbles is insufficient. A DAF algal harvesting model was developed to explain this observation by introducing mass-based floc size distributions and a bubble limitation into the white water blanket model. Moreover, the model revealed the importance of coagulation to increase floc-bubble collision and attachment, and the preferential interaction of bubbles with larger flocs, which limited the availability of bubbles to the smaller sized flocs. The harvesting efficiencies predicted by the model agree reasonably with experimental data obtained at different Al 3+ dosages, algal concentrations, and recycle ratios. Based on this modeling, critical parameters for efficient algal harvesting were identified.« less

Critical evaluation and modeling of algal harvesting using dissolved air flotation. DAF Algal Harvesting Modeling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Xuezhi; Hewson, John C.; Amendola, Pasquale

In our study, Chlorella zofingiensis harvesting by dissolved air flotation (DAF) was critically evaluated with regard to algal concentration, culture conditions, type and dosage of coagulants, and recycle ratio. Harvesting efficiency increased with coagulant dosage and leveled off at 81%, 86%, 91%, and 87% when chitosan, Al 3+, Fe 3+, and cetyl trimethylammonium bromide (CTAB) were used at dosages of 70, 180, 250, and 500 mg g -1, respectively. The DAF efficiency-coagulant dosage relationship changed with algal culture conditions. In evaluating the influence of the initial algal concentration and recycle ratio revealed that, under conditions typical for algal harvesting, wemore » found that it is possible that the number of bubbles is insufficient. A DAF algal harvesting model was developed to explain this observation by introducing mass-based floc size distributions and a bubble limitation into the white water blanket model. Moreover, the model revealed the importance of coagulation to increase floc-bubble collision and attachment, and the preferential interaction of bubbles with larger flocs, which limited the availability of bubbles to the smaller sized flocs. The harvesting efficiencies predicted by the model agree reasonably with experimental data obtained at different Al 3+ dosages, algal concentrations, and recycle ratios. Based on this modeling, critical parameters for efficient algal harvesting were identified.« less

Piezoelectric monolayers as nonlinear energy harvesters.

PubMed

López-Suárez, Miquel; Pruneda, Miguel; Abadal, Gabriel; Rurali, Riccardo

2014-05-02

We study the dynamics of h-BN monolayers by first performing ab-initio calculations of the deformation potential energy and then solving numerically a Langevine-type equation to explore their use in nonlinear vibration energy harvesting devices. An applied compressive strain is used to drive the system into a nonlinear bistable regime, where quasi-harmonic vibrations are combined with low-frequency swings between the minima of a double-well potential. Due to its intrinsic piezoelectric response, the nonlinear mechanical harvester naturally provides an electrical power that is readily available or can be stored by simply contacting the monolayer at its ends. Engineering the induced nonlinearity, a 20 nm2 device is predicted to harvest an electrical power of up to 0.18 pW for a noisy vibration of 5 pN.

Feasibility study of rainwater harvesting system in Sylhet City.

PubMed

Alam, R; Munna, G; Chowdhury, M A I; Sarkar, M S K A; Ahmed, M; Rahman, M T; Jesmin, F; Toimoor, M A

2012-01-01

In rural areas in Bangladesh, groundwater is the principal source of water supply. This underground water is available in considerable amount in shallow aquifers. It is free from pathogenic microorganisms and hence water-borne diseases. In plain lands, other than hilly areas, water supply to 97% rural population comes from tube-wells, which is regarded to be a phenomenal achievement in preserving public health. Besides, a dependable water supply system all throughout the country is offset by two factors: (a) high salinity in surface plus groundwater in coastal areas; (b) want of suitable groundwater aquifers in hilly areas and the high cost of setting up tube-wells due to deep underground water table and stony layers. However, presence of arsenic in underground water now poses a serious threat to the success once made in water supply by setting up of manually operated tube-wells in the village areas-the achievement is now on the brink of total collapse. In about 61 districts out of 64, presence of arsenic exceeds a quantity of 0.05 mg/1, a permissible limit as per Bangladeshi water quality standard. Harvesting rainwater can be a pragmatic solution to this problem, which is common in many places in Sylhet especially in the hilly areas on the north eastern part of the city. This can be an alternative source of drinking water because of availability of rainwater from March to October. Heavy rain occurs from end of May till mid September, which is commonly known as the rainy season. This paper focuses on the possibility of harvesting rainwater in rural communities and thickly populated urban areas of Sylhet. It also demonstrates the scopes of harvesting rainwater using simple and low-cost technology. With setting up of a carefully planned rainwater storage tank, a family can have all of its drinking water from rain. Planned use of rainwater through rainwater harvesting in the roof catchments may fulfill the entire annual domestic water demand of a family in the rural

Spatial multi-criteria analysis for selecting potential sites for aquifer recharge via harvesting and infiltration of surface runoff in north Jordan

NASA Astrophysics Data System (ADS)

Steinel, Anke; Schelkes, Klaus; Subah, Ali; Himmelsbach, Thomas

2016-11-01

In (semi-)arid regions, available water resources are scarce and groundwater resources are often overused. Therefore, the option to increase available water resources by managed aquifer recharge (MAR) via infiltration of captured surface runoff was investigated for two basins in northern Jordan. This study evaluated the general suitability of catchments to generate sufficient runoff and tried to identify promising sites to harvest and infiltrate the runoff into the aquifer for later recovery. Large sets of available data were used to create regional thematic maps, which were then combined to constraint maps using Boolean logic and to create suitability maps using weighted linear combination. This approach might serve as a blueprint which could be adapted and applied to similar regions. The evaluation showed that non-committed source water availability is the most restricting factor for successful water harvesting in regions with <200 mm/a rainfall. Experiences with existing structures showed that sediment loads of runoff are high. Therefore, the effectiveness of any existing MAR scheme will decrease rapidly to the point where it results in an overall negative impact due to increased evaporation if maintenance is not undertaken. It is recommended to improve system operation and maintenance, as well as monitoring, in order to achieve a better and constant effectiveness of the infiltration activities.

Underwater energy harvesting from a turbine hosting ionic polymer metal composites

NASA Astrophysics Data System (ADS)

Cellini, Filippo; Pounds, Jason; Peterson, Sean D.; Porfiri, Maurizio

2014-08-01

In this study, we explore the possibility of energy harvesting from fluid flow through a turbine hosting ionic polymer metal composites (IPMCs). Specifically, IPMC harvesters are embedded in the blades of a small-scale vertical axis water turbine to convert flow kinetics into electrical power via low-frequency flow-induced IPMC deformations. An in-house fabricated Savonius-Darrieus hybrid active turbine with three IPMCs is tested in a laboratory water tunnel to estimate the energy harvesting capabilities of the device as a function of the shunting electrical load. The turbine is shown to harvest a few nanowatt from a mean flow of 0.43\\;m\\;{{s}^{-1}} for shunting resistances in the range 100-1000\\;\\Omega . To establish a first understanding of the energy harvesting device, we propose a quasi-static hydroelastic model for the bending of the IPMCs and we utilize a black-box model to study their electromechanical response.

Biofilters for stormwater harvesting: understanding the treatment performance of key metals that pose a risk for water use.

PubMed

Feng, Wenjun; Hatt, Belinda E; McCarthy, David T; Fletcher, Tim D; Deletic, Ana

2012-05-01

A large-scale stormwater biofilter column study was conducted to evaluate the impact of design configurations and operating conditions on metal removal for stormwater harvesting and protection of aquatic ecosystems. The following factors were tested over 8 months of operation: vegetation selection (plant species), filter media type, filter media depth, inflow volume (loading rate), and inflow pollutant concentrations. Operational time was also integrated to evaluate treatment performance over time. Vegetation and filter type were found to be significant factors for treatment of metals. A larger filter media depth resulted in increased outflow concentrations of iron, aluminum, chromium, zinc, and lead, likely due to leaching and mobilization of metals within the media. Treatment of all metals except aluminum and iron was generally satisfactory with respect to drinking water quality standards, while all metals met standards for irrigation. However, it was shown that biofilters could be optimized for removal of iron to meet the required drinking water standards. Biofilters were generally shown to be resilient to variations in operating conditions and demonstrated satisfactory removal of metals for stormwater-harvesting purposes. © 2012 American Chemical Society

“Straight from the heavens into your bucket”: domestic rainwater harvesting as a measure to improve water security in a subarctic indigenous community

PubMed Central

Mercer, Nicholas; Hanrahan, Maura

2017-01-01

ABSTRACT Background: Black Tickle-Domino is an extremely water-insecure remote Inuit community in the Canadian subarctic that lacks piped-water. Drinking water consumption in the community is less than a third of the Canadian national average. Water insecurity in the community contributes to adverse health, economic, and social effects and requires urgent action. Objectives: To test the ability of domestic rainwater harvesting (DRWH) for the first time in the subarctic with the goal of improving water access and use in the community. Design: This project utilised quantitative weekly reporting of water collection and use, as well as focus group discussions. DRWH units were installed at seven water-insecure households chosen by the local government. Results were measured over a 6-week period in 2016. Results: Participants harvested 19.07 gallons of rainwater per week. General purpose water consumption increased by 17% and water retrieval efforts declined by 40.92%. Households saved $12.70 CDN per week. Participants reported perceived improvements to psychological health. Because no potable water was collected, drinking water consumption did not increase. The study identified additional water-insecurity impacts. Conclusion: DRWH cannot supply drinking water without proper treatment and filtration; however, it can be a partial remedy to water insecurity in the subarctic. DRWH is appropriately scaled, inexpensive, and participants identified several significant benefits. PMID:28422581

Rooftop level rainwater harvesting system

NASA Astrophysics Data System (ADS)

Traboulsi, Hayssam; Traboulsi, Marwa

2017-05-01

Unfortunately, in Lebanon and other countries in the Middle East region, water becomes scarcer than ever before, and over the last decades the demand on domestic water has increased due to population and economic growth. Although rainwater harvesting is considered to be a safe and reliable alternative source for domestic water, the inconvenience or impracticalities related to the cost and space needed for the construction of ground or underground storage tanks makes this practice not widely common in rural areas and rarely implemented in urban cities. This paper introduces a new technique to rainwater harvesting which can be easily used in both rural and urban areas: it collects and stores rainwater directly in tanks already installed on building roofs and not necessarily in special ground or underground ones. If widely adopted in Lebanon, this technique could help in: (1) collecting around 23 MCM (70 % of the current deficit in the domestic water supply) of rainwater and thus increasing the available water per m2 of building by 0.4 m3 per year, (2) saving around 7 % of the amount of electric energy usually needed to pump water from an aquifer well and ground or underground tank, and (3) considerably reducing the rate of surface runoff of rainwater at the coastal zones where rainwater is not captured at all and goes directly to the sea.

The Potential Role of Neglected and Underutilised Crop Species as Future Crops under Water Scarce Conditions in Sub-Saharan Africa

PubMed Central

Chivenge, Pauline; Mabhaudhi, Tafadzwanashe; Modi, Albert T.; Mafongoya, Paramu

2015-01-01

Modern agricultural systems that promote cultivation of a very limited number of crop species have relegated indigenous crops to the status of neglected and underutilised crop species (NUCS). The complex interactions of water scarcity associated with climate change and variability in sub-Saharan Africa (SSA), and population pressure require innovative strategies to address food insecurity and undernourishment. Current research efforts have identified NUCS as having potential to reduce food and nutrition insecurity, particularly for resource poor households in SSA. This is because of their adaptability to low input agricultural systems and nutritional composition. However, what is required to promote NUCS is scientific research including agronomy, breeding, post-harvest handling and value addition, and linking farmers to markets. Among the essential knowledge base is reliable information about water utilisation by NUCS with potential for commercialisation. This commentary identifies and characterises NUCS with agronomic potential in SSA, especially in the semi-arid areas taking into consideration inter alia: (i) what can grow under water-scarce conditions, (ii) water requirements, and (iii) water productivity. Several representative leafy vegetables, tuber crops, cereal crops and grain legumes were identified as fitting the NUCS category. Agro-biodiversity remains essential for sustainable agriculture. PMID:26016431

Architectures for wrist-worn energy harvesting

NASA Astrophysics Data System (ADS)

Rantz, R.; Halim, M. A.; Xue, T.; Zhang, Q.; Gu, L.; Yang, K.; Roundy, S.

2018-04-01

This paper reports the simulation-based analysis of six dynamical structures with respect to their wrist-worn vibration energy harvesting capability. This work approaches the problem of maximizing energy harvesting potential at the wrist by considering multiple mechanical substructures; rotational and linear motion-based architectures are examined. Mathematical models are developed and experimentally corroborated. An optimization routine is applied to the proposed architectures to maximize average power output and allow for comparison. The addition of a linear spring element to the structures has the potential to improve power output; for example, in the case of rotational structures, a 211% improvement in power output was estimated under real walking excitation. The analysis concludes that a sprung rotational harvester architecture outperforms a sprung linear architecture by 66% when real walking data is used as input to the simulations.

Flat Branch monitoring project: stream water temperature and sediment responses to forest cutting in the riparian zone

Treesearch

Barton D. Clinton; James M. Vose; Dick L. Fowler

2010-01-01

Stream water protection during timber-harvesting activities is of primary interest to forest managers. In this study, we examine the potential impacts of riparian zone tree cutting on water temperature and total suspended solids. We monitored stream water temperature and total suspended solids before and after timber harvesting along a second-order tributary of the...

Chemical composition and methane yield of reed canary grass as influenced by harvesting time and harvest frequency.

PubMed

Kandel, Tanka P; Sutaryo, Sutaryo; Møller, Henrik B; Jørgensen, Uffe; Lærke, Poul E

2013-02-01

This study examined the influence of harvest time on biomass yield, dry matter partitioning, biochemical composition and biological methane potential of reed canary grass harvested twice a month in one-cut (OC) management. The regrowth of biomass harvested in summer was also harvested in autumn as a two-cut management with (TC-F) or without (TC-U) fertilization after summer harvest. The specific methane yields decreased significantly with crop maturity that ranged from 384 to 315 and from 412 to 283 NL (normal litre) (kgVS)(-1) for leaf and stem, respectively. Approximately 45% more methane was produced by the TC-F management (5430Nm(3)ha(-1)) as by the OC management (3735Nm(3)ha(-1)). Specific methane yield was moderately correlated with the concentrations of fibre components in the biomass. Larger quantity of biogas produced at the beginning of the biogas assay from early harvested biomass was to some extent off-set by lower concentration of methane. Copyright © 2012 Elsevier Ltd. All rights reserved.

2011 High Plains and Northern Rolling Plains Cotton Harvest-Aid Guide

USDA-ARS?s Scientific Manuscript database

Harvest-aid chemicals are generally applied to hasten harvest of a mature crop and to reduce potential preharvest losses of lint yield and fiber quality. Proper use of harvest aids can result in earlier harvest, preservation of fiber quality, and fewer seed quality reductions due to field exposure. ...

2009 High plains and northern rolling plains cotton harvest-aid guide

USDA-ARS?s Scientific Manuscript database

Harvest-aid chemicals are generally applied to hasten harvest of a mature crop, and to reduce potential preharvest losses of lint yield and fiber quality. Proper use of harvest aids can result in earlier harvest, preservation of fiber quality, and fewer seed quality reductions due to field exposure....

2012 High Plains and Northern Rolling Plains Cotton harvest aid-guide

USDA-ARS?s Scientific Manuscript database

Harvest-aid chemicals are generally applied to hasten harvest of a mature crop, and to reduce potential preharvest losses of lint yield and fiber quality. Proper use of harvest aids can result in earlier harvest, preservation of fiber quality, and fewer seed quality reductions due to field exposure....

Expression of Arabidopsis SHN1 in Indian Mulberry (Morus indica L.) Increases Leaf Surface Wax Content and Reduces Post-harvest Water Loss

PubMed Central

Sajeevan, R. S.; Nataraja, Karaba N.; Shivashankara, K. S.; Pallavi, N.; Gurumurthy, D. S.; Shivanna, M. B.

2017-01-01

Mulberry (Morus species) leaf is the sole food for monophagous silkworms, Bombyx mori L. Abiotic stresses such as drought, salinity, and high temperature, significantly decrease mulberry productivity and post-harvest water loss from leaves influence silkworm growth and cocoon yield. Leaf surface properties regulate direct water loss through the cuticular layer. Leaf surface waxes, contribute for cuticular resistance and protect mesophyll cells from desiccation. In this study we attempted to overexpress AtSHN1, a transcription factor associated with epicuticular wax biosynthesis to increase leaf surface wax load in mulberry. Agrobacterium mediated in vitro transformation was carried out using hypocotyl and cotyledonary explants of Indian mulberry (cv. M5). Mulberry transgenic plants expressing AtSHN1 displayed dark green shiny appearance with increased leaf surface wax content. Scanning electron microscopy (SEM) and gas chromatograph–mass spectrometry (GC-MS) analysis showed change in pattern of surface wax deposition and significant change in wax composition in AtSHN1 overexpressors. Increased wax content altered leaf surface properties as there was significant difference in water droplet contact angle and diameter between transgenic and wild type plants. The transgenic plants showed significant improvement in leaf moisture retention capacity even 5 h after harvest and there was slow degradation of total buffer soluble protein in detached leaves compared to wild type. Silkworm bioassay did not indicate any undesirable effects on larval growth and cocoon yield. This study demonstrated that expression of AtSHN1, can increase surface wax load and reduce the post-harvest water loss in mulberry. PMID:28421085

Earth observing data and methods for advancing water harvesting technologies in the semi-arid rain-fed environments of India

USGS Publications Warehouse

Sharma, C.; Thenkabail, P.; Sharma, R. R.

2011-01-01

The paper develops approaches and methods of modeling and mapping land and water productivity of rain-fed crops in semi-arid environments of India using hyperspectral, hyperspatial, and advanced multispectral remote sensing data and linking the same to field-plot data and climate station data. The overarching goal is to provide information to advance water harvesting technologies in the agricultural croplands of the semi-arid environments of India by conducting research in a representative pilot site in Jodhpur, Rajasthan, India. ?? 2011 IEEE.

Development of an Energy Harvesting Device using Piezoceramic Materials

NASA Astrophysics Data System (ADS)

Kulkarni, Vainatey

Piezoelectric energy harvesters are increasingly being pursued for their potential to replace finite-life batteries in wireless sensor modules and for their potential to create self-powered devices. This work presents the development of a novel piezoelectric harvester that attempts to improve upon the power output limitations of current piezoelectric harvesting technology. This novel harvester uses the concept of torsion on a tube to produce shear stresses and hence uses improved piezoelectric properties of the shear mode of piezoceramics to generate higher power outputs. This concept is first presented in this work and a proof-of-concept prototype is utilized to experimentally demonstrate the validity of this novel device. After this, the behaviour of the novel harvester is explored through an investigation into three cross-section geometries of the torsion tube and varying geometries of the eccentric mass using three different comparison metrics. Through this, it is observed that configurations with higher torsional compliance and high eccentric mass inertias have the potential for the highest power output and highest harvester effectiveness. However, the mechanical damping in the system is also found to significantly impact the harvester output resulting in prototypes of the various configurations not performing as expected. As a result of this discrepancy, the factors affecting the performance of the harvester are analyzed in greater detail through the development of a mathematical model that is then used to develop a set of guidelines to direct the design of a torsion harvester for a desired application. These guidelines are then used to develop an improved torsion harvester with a demonstrated ability to produce 1.2 mW of output power at its resonant frequency to power a wireless sensor module. Finally, the use of alternative materials such as single crystals of PMN-PT in the torsion harvester is also examined. Through finite element simulations and with

Assessing efficiency and economic viability of rainwater harvesting systems for meeting non-potable water demands in four climatic zones of China

NASA Astrophysics Data System (ADS)

Zhang, S.; Jing, X.

2017-12-01

Rainwater harvesting is now increasingly used to manage urban flood and alleviate water scarcity crisis. In this study, a computational tool based on water balance equation is developed to assess stormwater capture and water saving efficiency and economic viability of rainwater harvesting systems (RHS) in eight cities across four climatic zones of China. It requires daily rainfall, contributing area, runoff losses, first flush volume, storage capacity, daily water demand and economic parameters as inputs. Three non-potable water demand scenarios (i.e., toilet flushing, lawn irrigation, and combination of them) are considered. The water demand for lawn irrigation is estimated using the Cropwat 8.0 and Climwat 2.0. Results indicate that higher water saving efficiency and water supply time reliability can be achieved for RHS with larger storage capacities, for lower water demand scenarios and located in more humid regions, while higher stormwater capture efficiency is associated with larger storage capacity, higher water demand scenarios and less rainfall. For instance, a 40 m3 RHS in Shanghai (humid climate) for lawn irrigation can capture 17% of stormwater, while its water saving efficiency and time reliability can reach 96 % and 98%, respectively. The water saving efficiency and time reliability of a 20 m3 RHS in Xining (semi-arid climate) for toilet flushing are 19% and 16%, respectively, but it can capture 63% of stormwater. With the current values of economic parameters, economic viability of RHS can be achieved in humid and semi-humid regions for reasonably designed RHS; however, it is not financially viable to install RHS in arid regions as the benefit-cost ratio is much smaller than 1.0.

Influence of forest and rangeland management on anadromous fish habitat in Western North America: timber harvest.

Treesearch

T.W. Chamberlin

1982-01-01

The water and land-system processes through which timber harvesting affects anadromous fish habitat in western North America are discussed. The effects of timber harvesting on the water balance that regulates streamflow are evaluated, as are direct influences of harvesting on slope stability, erosion, and the introduction of debris in to stream channels. The effects of...

Water saving at the field scale with Irrig-OH, an open-hardware environment device for soil water potential monitoring and irrigation management

NASA Astrophysics Data System (ADS)

Masseroni, Daniele; Facchi, Arianna; Gandolfi, Claudio

2015-04-01

Sustainability of irrigation practices is an important objective which should be pursued in many countries, especially in areas where water scarcity causes strong conflicts among the different water uses. The efficient use of water is a key factor in coping with the food demand of an increasing world population and with the negative effects of the climate change on water resources availability in many areas. In this complex context, it is important that farmers adopt instruments and practices that enable a better management of water at the field scale, whatever the irrigation method they adopt. This work presents the hardware structure and the functioning of an open-hardware microstation based on the Arduino technology, called Irrig-OH, which allows the continuous and low-cost monitoring of the soil water potential (SWP) in the root zone for supporting the irrigation scheduling at the field scale. In order to test the microstation, an experiment was carried out during the agricultural season 2014 at Lodi (Italy), with the purpose of comparing the farmers' traditional management of irrigation of a peach variety and the scheduling based on the SWP measurements provided by the microstation. Additional measurements of leaf water potential (LWP), stomatal resistance, transpiration (T), crop water stress index (CWSI) and fruit size evolution were performed respectively on leafs and fruits for verifying the plant physiological responses on different SWP levels in soil. At the harvesting time, the peach production in term of quantity and quality (sucrose content was measured by a rifractometer over a sample of one hundred fruits) of the two rows were compared. Irrigation criteria was changed with respect to three macro-periods: up to the endocarp hardening phase (begin of May) soil was kept well watered fixing the SWP threshold in the first 35 cm of the soil profile at -20 kPa, during the pit hardening period (about the entire month of May) the allowed SWP threshold was

Momentum harvesting techniques for solar system travel

NASA Technical Reports Server (NTRS)

Willoughby, Alan J.

1990-01-01

Astronomers are lately estimating there are 400,000 Earth visiting asteroids larger than 100 meters in diameter. These asteroids are accessible sources of building materials, propellants, oxygen, water, and minerals which also constitute a huge momentum reserve, potentially usable for travel throughout the solar system. To use this momentum, these stealthy objects must be tracked and the extraction of the momentum wanted must be learned. Momentum harvesting by momentum transfer from asteroid to spacecraft, and by using the momentum of the extraterrestrial material to help deliver itself to the destination are discussed. A net and tether concept is the suggested means of asteroid capture, the basic momentum exchange process. The energy damping characteristics of the tether will determine the velocity mismatch that can be tolerated, and hence the amount of momentum that can be harvested per capture. As it plays out of its reel, drag on the tether steadily accelerates the spacecraft. A variety of concepts for riding and using the asteroid after capture are discussed. The hitchhiker uses momentum transfer only. The beachcomber, the caveman, the swinger, the prospector, and the rock wrecker also take advantage of raw asteroidal materials. The chemist and the hijacker go further, they process the asteroid into propellant. Or, an 'asteroid railway system' could evolve with each hijacked asteroid becoming a scheduled train. Travelers could board the space railway system assured that water, oxygen, and propellants await them.

Evaluating Changes in Distributions of Summer Stream Temperature following Forest Harvest

NASA Astrophysics Data System (ADS)

Johnson, S. L.; Reiter, M.; Jones, J.

2016-12-01

Stream temperature heat budgets are influenced by numerous processes; changes in incoming radiation have been shown to be a major driver of increased stream temperatures. Maximum daily temperature is a commonly used metric for evaluating stream temperature responses to land use. However, single metrics are not able to fully represent the magnitude and duration of temperatures experienced by instream biota. Analyses that make use of all the data: a) more accurately characterize shifts in summer stream temperature regimes, b) quantify potential exposure to critical and non-critical temperatures, and c) help researchers and managers to better understand stream temperature responses to manipulation of streamside and watershed vegetation. Here we examine the distributions of summer stream temperatures before and after forest harvest in the Trask River Watershed Study, in northwestern Oregon. We studied 15 small streams for 10 years; half of the sites had their catchments clearcut harvested in 2012. Four sites had no buffers, with some leave trees, and three sites had 25 ft buffers on both sides. Temperatures were measured during at 30min intervals. Even though these streams are generally cold, we observed high spatial and temporal variation among sites and years, with some sites having normally distributed temperatures, while others showed skewed distributions and long tails. Forest cover, aspect or elevation were not good predictors of temperature distributions pre-harvest. Preliminary analyses using travel time of the stream water suggest that sites with hyporheic flows had narrower distributions of temperatures. After harvest, sites without buffers showed the greatest shift in distributions of temperatures and widest temperature ranges, while sites with narrow buffers showed little change. We are exploring the implications of shifts in temperature distributions before and after harvest against the known thermal tolerances for the dominant resident species (Ascaphus

Harvesting energy from the marine sediment--water interface.

PubMed

Reimers, C E; Tender, L M; Fertig, S; Wang, W

2001-01-01

Pairs of platinum mesh or graphite fiber-based electrodes, one embedded in marine sediment (anode), the other in proximal seawater (cathode), have been used to harvest low-level power from natural, microbe established, voltage gradients at marine sediment-seawater interfaces in laboratory aquaria. The sustained power harvested thus far has been on the order of 0.01 W/m2 of electrode geometric area but is dependent on electrode design, sediment composition, and temperature. It is proposed that the sediment/anode-seawater/cathode configuration constitutes a microbial fuel cell in which power results from the net oxidation of sediment organic matter by dissolved seawater oxygen. Considering typical sediment organic carbon contents, typical fluxes of additional reduced carbon by sedimentation to sea floors < 1,000 m deep, and the proven viability of dissolved seawater oxygen as an oxidant for power generation by seawater batteries, it is calculated that optimized power supplies based on the phenomenon demonstrated here could power oceanographic instruments deployed for routine long-term monitoring operations in the coastal ocean.

Microbiological Values of Rainwater Harvested in Adelaide

PubMed Central

Edwards, John W.

2018-01-01

In Australia, rainwater is an important source of water for many households. Unlike municipal water, rainwater is often consumed untreated. This study investigated the potential contamination of rainwater by microorganisms. Samples from 53 rainwater tanks across the Adelaide region were collected and tested using Colilert™ IDEXX Quanti-Tray*/2000. Twenty-eight out of the 53 tanks (53%) contained Escherichia coli. Samples collected from ten tanks contained E. coli at concentrations exceeding the limit of 150 MPN/100 mL for recreational water quality. A decline in E. coli was observed in samples collected after prolonged dry periods. Rainwater microbiological values depended on the harvesting environment conditions. A relationship was found between mounted TV antenna on rooftops and hanging canopies; and E. coli abundance. Conversely, there was no relationship between seasonality and E. coli or roof and tank structure materials and E. coli. In several tanks used for drinking water, samples collected prior to and after filtration showed that the filtration systems were not always successful at completely removing E. coli. These results differed from a study undertaken in the laboratory that found that a commercially available in-bench 0.45 µm filter cartridge successfully reduced E. coli in rainwater to 0 MPN/100 mL. After running a total of 265 L of rainwater which contained high levels of E. coli through the filter (half of the advertised filter lifespan), the filter cartridge became blocked, although E. coli remained undetected in filtered water. The difference between the laboratory study and field samples could be due to improper maintenance or installation of filters or recontamination of the faucet after filtration. The presence of E. coli in water that is currently used for drinking poses a potential health concern and indicates the potential for contamination with other waterborne pathogens. PMID:29419793

Feasibility study of rainwater harvesting for domestic use (Case study: West Jakarta rainfall data)

NASA Astrophysics Data System (ADS)

Kartolo, Jason; Kusumawati, Elly

2017-11-01

Rainwater Harvesting system is one of considerable choice to reduce flood in Jakarta, moreover it helps to reduce main tap water consumption. In this study, rainwater is used for flushing toilet and watering garden for domestic use. Rainwater harvesting system is examined for 60 m2 and 90 m2 housing area, using rainfall data from Cengkareng station in West Jakarta. Two type of rainwater harvesting reservoir is designed, those are ground reservoir and underground reservoir. From the analysis, it finds that 60 m2 house feasible for 1 m3 ground reservoir and 9 m3 underground reservoir. Meanwhile for 90 m2 house 2 m3 tanks ground reservoir and 14 m3 tank underground reservoir is feasible. Underground reservoir retain more water volume so it provide higher rate of water supply. The cost of underground reservoir is lower 60% - 70% than ground reservoir. Even though rainwater harvesting is technically feasible for housing, it is not economically feasible. The construction cost is higher than the benefit of reduced tap water consumption.

Monitoring on The Quality and Quantity of DIY Rainwater Harvesting System

NASA Astrophysics Data System (ADS)

Kasmin, H.; Bakar, N. H.; Zubir, M. M.

2016-07-01

Rainwater harvesting is an alternative sources of water supply and can be used for potable and non-potable uses. It could helps to store treated rainwater for more beneficial use and also for flood mitigation. Sustainable approach for flooding problem reduction in urban areas is by slowing down the rate of surface runoff flows at source by providing more storage area/tank. In order to understand the performance of a rainwater harvesting system (RWH), a preliminary monitoring on a ‘do it yourself’ (DIY) RWH model with additional first -flush strategy for water quality treatment was done. The main concept behind first flush diversion is to prevent initial polluted rainwater from entering the storage tank. Based on seven rainfall events observed in Parit Raja, both quality and quantity of the rainfalls were analysed. For rainwater quality, the samples from first flush diverter and storage tank were taken to understand their performance based on pH, dissolved oxygen (DO), turbidity, total dissolved solid (TDS), total suspended solid (TSS), chemical oxygen demand (COD) and biochemical oxygen demand (BOD) parameters. While for rainwater quantity, hydrograph analysis were done based on the performance of total rainfall and runoff, peak flow of rainfall and runoff; and delayed time parameters. Based on Interim National Water Quality Standard (INWQS) and National Drinking Water Quality Standard (NDWQS), first flush diverter apparently helps on water quality improvement in storage tanks when pH, DO, TDS, TSS and turbidity were classified as Class I (INWQS) and is allowable for drinking; but BOD and COD parameters were classified as Class III (INWQS). Hence, it has potential to be used as potable usage but will need extensive treatment to reduce its poor microbial quality. Based on the maximum observed rainfall event which had total volume of 3195.5 liter, had peakflow reduction from 0.00071 m3/s to 0.00034 m3/s and delayed runoff between 5 and 10 minutes after rainfall

Soil and water management in the shortleaf pine ecosystem

Treesearch

Edwin L. Miller

1986-01-01

The opportunities for achieving watershed management goals in the process of timber management in the range of shortleaf pine are excellent. Water yield increases may occur with forest harvest but with little or no adverse watershed effects. Peak or flood flows for major storms are little affected by forest harvest. Serious erosion potentials exist when inappropriate...

Harvesting Vibrational Energy Using Material Work Functions

PubMed Central

Varpula, Aapo; Laakso, Sampo J.; Havia, Tahvo; Kyynäräinen, Jukka; Prunnila, Mika

2014-01-01

Vibration energy harvesters scavenge energy from mechanical vibrations to energise low power electronic devices. In this work, we report on vibration energy harvesting scheme based on the charging phenomenon occurring naturally between two bodies with different work functions. Such work function energy harvester (WFEH) is similar to electrostatic energy harvester with the fundamental distinction that neither external power supplies nor electrets are needed. A theoretical model and description of different operation modes of WFEHs are presented. The WFEH concept is tested with macroscopic experiments, which agree well with the model. The feasibility of miniaturizing WFEHs is shown by simulating a realistic MEMS device. The WFEH can be operated as a charge pump that pushes charge and energy into an energy storage element. We show that such an operation mode is highly desirable for applications and that it can be realised with either a charge shuttle or with switches. The WFEH is shown to give equal or better output power in comparison to traditional electrostatic harvesters. Our findings indicate that WFEH has great potential in energy harvesting applications. PMID:25348004

Harvested rainwater quality before and after treatment in six ...

EPA Pesticide Factsheets

Rainwater harvesting (RWH) is an alternative method of providing water for indoor domestic use, but the water quality after treatment and distribution at individual residences is not well documented. In this study, water quality parameters were measured at the cistern and indoor cold-water taps of six residential RWH systems that use various treatment processes. Potential human pathogens (Mycobacterium avium, Mycobacterium intracellulare, Aspergillus flavus, Aspergillus fumigatus, and Aspergillus niger) were found frequently in cisterns and in treated rainwater delivered at the tap; Legionella pneumophila was not detected as frequently, but it persisted in a system after its first detection. The observed decreases in bacterial concentrations from the cistern to the tap after filtration/ ultraviolet (UV) treatment and distribution were less than expected; this suggests deficiencies in the effectiveness of the filtration/UV processes employed and/or degradation in water quality in the distribution system due to the absence of a disinfectant residual. Determination of the disinfection efficiency occuring in home treatment processes. Molecular analysis of rainwater before and after treatment. First study to include the monitoring of opportunistic fungal pathogens.

Impacts of using rainwater tanks on stormwater harvesting and runoff quality.

PubMed

Khastagir, A; Jayasuriya, L N N

2010-01-01

The popularity of rainwater use in Australia depends completely on the individual householder's preference. The quality of reticulated water supplies in major cities of Australia is far superior to water stored in rainwater tanks. However, due to persistent drought and the implementation of stringent water restrictions, cities such as Melbourne have encouraged the use of rainwater harvesting within the property. The benefits of trapping stormwater within a property and using it effectively also reduce polluted runoff excess reaching receiving water. The study reported herein focuses on the effectiveness of rainwater tanks as a potential water sensitive urban design element used to manage stormwater using the MUSIC model. The study shows that the installation of a 3 kL tank reduces hydraulic loading by 75%, Total Suspended Solids by 97%, Total Phosphorous by 90% and Total Nitrogen by 81% if the rainwater stored in the tank is used to meet the indoor demand (toilet flushing and laundry use) as well as the outdoor demand (garden watering).

Harvesting Broad Frequency Band Blue Energy by a Triboelectric-Electromagnetic Hybrid Nanogenerator.

PubMed

Wen, Zhen; Guo, Hengyu; Zi, Yunlong; Yeh, Min-Hsin; Wang, Xin; Deng, Jianan; Wang, Jie; Li, Shengming; Hu, Chenguo; Zhu, Liping; Wang, Zhong Lin

2016-07-26

Ocean wave associated energy is huge, but it has little use toward world energy. Although such blue energy is capable of meeting all of our energy needs, there is no effective way to harvest it due to its low frequency and irregular amplitude, which may restrict the application of traditional power generators. In this work, we report a hybrid nanogenerator that consists of a spiral-interdigitated-electrode triboelectric nanogenerator (S-TENG) and a wrap-around electromagnetic generator (W-EMG) for harvesting ocean energy. In this design, the S-TENG can be fully isolated from the external environment through packaging and indirectly driven by the noncontact attractive forces between pairs of magnets, and W-EMG can be easily hybridized. Notably, the hybrid nanogenerator could generate electricity under either rotation mode or fluctuation mode to collect energy in ocean tide, current, and wave energy due to the unique structural design. In addition, the characteristics and advantages of outputs indicate that the S-TENG is irreplaceable for harvesting low rotation speeds (<100 rpm) or motion frequencies (<2 Hz) energy, which fits the frequency range for most of the water wave based blue energy, while W-EMG is able to produce larger output at high frequencies (>10 Hz). The complementary output can be maximized and hybridized for harvesting energy in a broad frequency range. Finally, a single hybrid nanogenerator unit was demonstrated to harvest blue energy as a practical power source to drive several LEDs under different simulated water wave conditions. We also proposed a blue energy harvesting system floating on the ocean surface that could simultaneously harvest wind, solar, and wave energy. The proposed hybrid nanogenerator renders an effective and sustainable progress in practical applications of the hybrid nanogenerator toward harvesting water wave energy offered by nature.

Balancing-out floods and droughts: Opportunities to utilize floodwater harvesting and groundwater storage for agricultural development in Thailand

NASA Astrophysics Data System (ADS)

Pavelic, Paul; Srisuk, Kriengsak; Saraphirom, Phayom; Nadee, Suwanchai; Pholkern, Kewaree; Chusanathas, Sumrit; Munyou, Sitisak; Tangsutthinon, Theerasak; Intarasut, Teerawash; Smakhtin, Vladimir

2012-11-01

SummaryThailand's naturally high seasonal endowment of water resources brings with it the regularly experienced problems associated with floods during the wet season and droughts during the dry season. Downstream-focused engineering solutions that address flooding are vital, but do not necessarily capture the potential for basin-scale improvements to water security, food production and livelihood enhancement. Managed aquifer recharge, typically applied to annual harvesting of wet season flows in dry climates, can also be applied to capture, store and recover episodic extreme flood events in humid environments. In the Chao Phraya River Basin it is estimated that surplus flows recorded downstream above a critical threshold could be harvested and recharged within the shallow alluvial aquifers in a distributed manner upstream of flood prone areas without significantly impacting existing large-medium storages or the Gulf and deltaic ecosystems. Capturing peak flows approximately 1 year in four by dedicating around 200 km2 of land to groundwater recharge would reduce the magnitude of flooding and socio-economic impacts and generate around USD 250 M/year in export earnings for smallholder rainfed farmers through dry season cash cropping without unduly compromising the demands of existing water users. It is proposed that farmers in upstream riparian zones be co-opted as flood harvesters and thus contribute to improved floodwater management through simple water management technologies that enable agricultural lands to be put to higher productive use. Local-scale site suitability and technical performance assessments along with revised governance structures would be required. It is expected that such an approach would also be applicable to other coastal-discharging basins in Thailand and potentially throughout the Asia region.

Concurrent Harvesting of Ambient Energy by Hybrid Nanogenerators for Wearable Self-Powered Systems and Active Remote Sensing.

PubMed

Zheng, Haiwu; Zi, Yunlong; He, Xu; Guo, Hengyu; Lai, Ying-Chih; Wang, Jie; Zhang, Steven L; Wu, Changsheng; Cheng, Gang; Wang, Zhong Lin

2018-05-02

Harvesting energy available from ambient environment is highly desirable for powering personal electronics and health applications. Due to natural process and human activities, steam can be produced by boilers, human perspiration, and the wind exists ubiquitously. In the outdoor environment, these two phenomena usually exist at the same place, which contain heat and mechanical energies simultaneously. However, previous studies have isolated them as separate sources of energy to harvest and hence failed to utilize them effectively. Herein, we present unique hybrid nanogenerators for individually/simultaneously harvesting thermal energy from water vapors and mechanical energy from intermittent wind blowing from the bottom side, which consist of a wind-driven triboelectric nanogenerator (TENG) and pyroelectric-piezoelectric nanogenerators (PPENGs). The output power of the PPENG and the TENG can be up to about 184.32 μW and 4.74 mW, respectively, indicating the TENG plays the dominant role. Our hybrid nanogenerators could provide different applications such as to power digital watch and enable self-powered sensing with wireless transmission. The device could also be further integrated into a face mask for potentially wearable applications. This work not only provides a promising approach for renewable energy harvesting but also enriches potential applications for self-powered systems and wireless sensors.

Self-organized multi-species vegetation patterns: the role of connectivity of environmental niches in natural water harvesting ecosystems

NASA Astrophysics Data System (ADS)

Callegaro, Chiara; Ursino, Nadia

2016-04-01

Self-organizing vegetation patterns are natural water harvesting systems in arid and semi-arid regions of the world and should be imitated when designing man-managed water-harvesting systems for rain-fed crop. Disconnected vegetated and bare zones, functioning as a source-sink system of resources, sustain vegetation growth and reduce water and soil losses. Mechanisms such as soil crusting over bare areas and soil loosening in vegetated areas feed back to the local net facilitation effect and contribute to maintain the patterned landscape structure. Dis-connectivity of run-off production and run-on infiltration sites reduces runoff production at the landscape scale, and increases water retention in the vegetated patches. What is the effect of species adaptation to different resource niches on the landscape structure? A minimal model for two coexisting species and soil moisture balance was formulated, to improve our understanding of the effects of species differentiation on the dynamics of plants and water at single-pattern and landscape scale within a tiger bush type ecosystem. A basic assumption of our model was that soil moisture availability is a proxy for the environmental niche of plant species. Connectivity and dis-connectivity of specific niches of adaptation of two differing plant species was an input parameter of our model, in order to test the effect of coexistence on the ecosystem structure. The ecosystem structure is the model outcome, including: patterns persistence of coexisting species; patterns persistence of one species with exclusion of the other; patterns decline with just one species surviving in a non organized structure; bare landscape with loss of both species. Results suggest that pattern-forming-species communities arise as a result of complementary niche adaptation (niche dis-connecivity), whereas niche superposition (niche connectivity) may lead to impoverishment of environmental resources and loss of vegetation cover and diversity.

Performance of a large building rainwater harvesting system.

PubMed

Ward, S; Memon, F A; Butler, D

2012-10-15

Rainwater harvesting is increasingly becoming an integral part of the sustainable water management toolkit. Despite a plethora of studies modelling the feasibility of the utilisation of rainwater harvesting (RWH) systems in particular contexts, there remains a significant gap in knowledge in relation to detailed empirical assessments of performance. Domestic systems have been investigated to a limited degree in the literature, including in the UK, but there are few recent longitudinal studies of larger non-domestic systems. Additionally, there are few studies comparing estimated and actual performance. This paper presents the results of a longitudinal empirical performance assessment of a non-domestic RWH system located in an office building in the UK. Furthermore, it compares actual performance with the estimated performance based on two methods recommended by the British Standards Institute - the Intermediate (simple calculations) and Detailed (simulation-based) Approaches. Results highlight that the average measured water saving efficiency (amount of mains water saved) of the office-based RWH system was 87% across an 8-month period, due to the system being over-sized for the actual occupancy level. Consequently, a similar level of performance could have been achieved using a smaller-sized tank. Estimated cost savings resulted in capital payback periods of 11 and 6 years for the actual over-sized tank and the smaller optimised tank, respectively. However, more detailed cost data on maintenance and operation is required to perform whole life cost analyses. These findings indicate that office-scale RWH systems potentially offer significant water and cost savings. They also emphasise the importance of monitoring data and that a transition to the use of Detailed Approaches (particularly in the UK) is required to (a) minimise over-sizing of storage tanks and (b) build confidence in RWH system performance. Copyright © 2012 Elsevier Ltd. All rights reserved.

Relationship between antibiotic- and disinfectant-resistance profiles in bacteria harvested from tap water.

PubMed

Khan, Sadia; Beattie, Tara K; Knapp, Charles W

2016-06-01

Chlorination is commonly used to control levels of bacteria in drinking water; however, viable bacteria may remain due to chlorine resistance. What is concerning is that surviving bacteria, due to co-selection factors, may also have increased resistance to common antibiotics. This would pose a public health risk as it could link resistant bacteria in the natural environment to human population. Here, we investigated the relationship between chlorine- and antibiotic-resistances by harvesting 148 surviving bacteria from chlorinated drinking-water systems and compared their susceptibilities against chlorine disinfectants and antibiotics. Twenty-two genera were isolated, including members of Paenibacillus, Burkholderia, Escherichia, Sphingomonas and Dermacoccus species. Weak (but significant) correlations were found between chlorine-tolerance and minimum inhibitory concentrations against the antibiotics tetracycline, sulfamethoxazole and amoxicillin, but not against ciprofloxacin; this suggest that chlorine-tolerant bacteria are more likely to also be antibiotic resistant. Further, antibiotic-resistant bacteria survived longer than antibiotic-sensitive organisms when exposed to free chlorine in a contact-time assay; however, there were little differences in susceptibility when exposed to monochloramine. Irrespective of antibiotic-resistance, spore-forming bacteria had higher tolerance against disinfection compounds. The presence of chlorine-resistant bacteria surviving in drinking-water systems may carry additional risk of antibiotic resistance. Copyright © 2016 Elsevier Ltd. All rights reserved.

Rainwater Harvesting for Military Installations -The Time is Now

DTIC Science & Technology

2010-06-01

Alternate Water Sources US Army Corps of Engineers® Engineer Research and Development Center - Water Reuse - Desalination - Produced Water...RAINWATER HARVESTING - Ground Water Recharge - Graywater Reuse - Sewer Mining Other Water Use/Alternate Water Sources Options What can be done to increase...WATER NO TOME El AGUA .. US Army Corps of Engineers® Engineer Research and Development Center Mitchell Physics RWH 386,800 GPY AC 1,058,300 GPY

Sizing a rainwater harvesting cistern by minimizing costs

NASA Astrophysics Data System (ADS)

Pelak, Norman; Porporato, Amilcare

2016-10-01

Rainwater harvesting (RWH) has the potential to reduce water-related costs by providing an alternate source of water, in addition to relieving pressure on public water sources and reducing stormwater runoff. Existing methods for determining the optimal size of the cistern component of a RWH system have various drawbacks, such as specificity to a particular region, dependence on numerical optimization, and/or failure to consider the costs of the system. In this paper a formulation is developed for the optimal cistern volume which incorporates the fixed and distributed costs of a RWH system while also taking into account the random nature of the depth and timing of rainfall, with a focus on RWH to supply domestic, nonpotable uses. With rainfall inputs modeled as a marked Poisson process, and by comparing the costs associated with building a cistern with the costs of externally supplied water, an expression for the optimal cistern volume is found which minimizes the water-related costs. The volume is a function of the roof area, water use rate, climate parameters, and costs of the cistern and of the external water source. This analytically tractable expression makes clear the dependence of the optimal volume on the input parameters. An analysis of the rainfall partitioning also characterizes the efficiency of a particular RWH system configuration and its potential for runoff reduction. The results are compared to the RWH system at the Duke Smart Home in Durham, NC, USA to show how the method could be used in practice.

Big bluestem and switchgrass feedstock harvest timing: Nitrous oxide response to feedstock harvest timing

USDA-ARS?s Scientific Manuscript database

Switchgrass (Panicum virgatum L.) and big bluestem (Andropogon gerdardii Vitman) are potential bioenergy feedstocks. Feedstock storage limitations, labor constraints for harvest, and environmental benefits provided by perennials are rationales for developing localized perennial feedstock as an alter...

GIS methods for sustainable stormwater harvesting and storage using remote sensing for land cover data - location assessment.

PubMed

Mahmoud, Shereif H; Alazba, A A; Adamowski, J; El-Gindy, A M

2015-09-01

Identification of potential sites for rainwater harvesting (RWH) is an important step toward maximizing water availability and land productivity in arid semiarid regions. Characterised as a "water scarce" country, Egypt has limited fresh water supplies, and is expected to suffer from water stress by the year 2030. Therefore, it is important to develop any means available to supply water and maintain human habitability in a sustainable manner. Practiced or simply indispensable in many countries around the world, rainwater harvesting (RWH) promotes a sustainable and efficient manner of exploiting water resources. In the present study, suitable areas for sustainable stormwater harvesting and storage in Egypt were identified using remote sensing for land cover data - location assessment linked to a decision support system (DSS). The DSS took into consideration a combination of thematic layers such as rainfall surplus, slope, potential runoff coefficient (PRC), land cover/use, and soil texture. Taking into account five thematic layers, the spatial extents of RWH suitability areas were identified by an analytical hierarchy process (AHP). The model generated a RWH map with five categories of suitability: excellent, good, moderate, poor and unsuitable. The spatial distribution of these categories in the area investigated was such that 4.8% (47910 km(2)) and 14% (139739 km(2)) of the study area was classified as excellent or good in terms of RWH, respectively, while 30.1% (300439 km(2)), 47.6% (474116 km(2)) and 3.5% (34935 km(2)) of the area were classified as moderate, unsuitable and poor, respectively. Most of the areas with excellent to good suitability had slopes of between 2% and 8% and were intensively cultivated areas. The major soil type in the excellent suitability areas was loam, while rainfall ranged from 100 to 200 mm yr(-1). The use of a number of RWH sites in the excellent areas is recommended to ensure successful implementation of RWH systems.

Quality assessment of roof-harvested rainwater in the West Bank, Palestinian Authority.

PubMed

Daoud, A K; Swaileh, K M; Hussein, R M; Matani, M

2011-09-01

Rain harvesting is becoming more common in the Palestinian Territories as a result of drinking water scarcity. Although it might pose serious human health risk, this water is being consumed without treatment in many areas of the West Bank. The present study evaluates the physicochemical and microbial quality of harvested rainwater that is used as potable water in the West Bank. Samples from roof-harvested rainwater storage tanks (n = 42) were collected in summer (SS) 2006/winter (WS) 2007. Physicochemical parameters measured were: temperature, pH, electrical conductivity, salinity, total dissolved solids, turbidity, nitrate, copper and lead. With few exceptions, all these parameters were within WHO guideline values. All samples (100%) were found to contain coliforms and to be heavily contaminated with heterotrophic bacteria. About 67% of all samples were contaminated with fecal coliforms. Specific PCR technique confirmed the presence of five pathogenic microorganisms that can be ordered according to their prevalence as: Citrobacter (83%) > Acinetobacter (78%) > Aeromonas (52%) > Pseudomonas and Campylobacter (7%). Prevalence of microorganisms in SS was higher than in WS. Although the physicochemical quality of most harvested rainwater samples was in accordance with WHO guidelines for drinking water, stored rainwater was significantly contaminated with bacteria resulting in significant human health risk from infectious diseases.

A decision support system for forest harvest planning in North Carolina

Treesearch

D.G. Jones

2010-01-01

Forest preharvest planning (FPP) can enhance recognition of environmentally-sensitive areas in advance of forest harvesting, including soil and water resources. While preharvest planning is often a standard component of many forest harvesting operations, either explicitly with paper-based checklists or implicitly with best professional judgment, Geographic Information...

Controls on the quality of harvested rainwater in residential systems

NASA Astrophysics Data System (ADS)

Sojka, S. L.; Phung, D.; Hollingsworth, C.

2014-12-01

Rainwater harvesting systems, in which runoff from roofs is collected and used for irrigation, toilets and other purposes, present a viable solution to limited freshwater supplies and excess stormwater runoff. However, a lack of data on the quality of harvested rainwater hinders adoption of rainwater harvesting systems and makes development of rainwater harvesting regulations difficult. We conducted monthly surveys of 6 existing residential rainwater harvesting systems ranging in age from 1 to 11 years measuring pH, temperature, dissolved oxygen, total suspended solids, dissolved organic carbon, and coliform bacteria. We also examined a subset of the samples for iron, lead, mercury and arsenic. Many of the systems routinely met the water quality requirements for non-potable use without additional treatment, which is often required by regulations. In addition, while previous studies have shown that roof runoff contains heavy metals, the water in all systems showed very low or undetectable levels of metal contamination. Coliform bacteria concentration ranged from 20 to greater than 1400 CFU's per 100 mL and correlated with total suspended solids, which ranged from 2 - 7 mg l-1. The relationship between suspended solids and bacteria population was confirmed in a controlled experiment on the impact of filtering the rainwater before storage. Filtration decreased total suspended solids and total coliforms and increased dissolved oxygen concentration. This project provides insight into the effects of system design and a baseline assessment of the quality of harvested rainwater in existing systems.

Design and engineering of water-soluble light-harvesting protein maquettes

DOE PAGES

Kodali, Goutham; Mancini, Joshua A.; Solomon, Lee A.; ...

2017-01-01

Design of nanometer scale artificial light harvesting and charge separating proteins enables reengineering to overcome the limitations of natural selection for efficient systems that better meet human energetic needs.

Design and engineering of water-soluble light-harvesting protein maquettes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kodali, Goutham; Mancini, Joshua A.; Solomon, Lee A.

Design of nanometer scale artificial light harvesting and charge separating proteins enables reengineering to overcome the limitations of natural selection for efficient systems that better meet human energetic needs.

Optical Sensing of Weed Infestations at Harvest.

PubMed

Barroso, Judit; McCallum, John; Long, Dan

2017-10-19

Kochia ( Kochia scoparia L.), Russian thistle ( Salsola tragus L.), and prickly lettuce ( Lactuca serriola L.) are economically important weeds infesting dryland wheat ( Triticum aestivum L.) production systems in the western United States. Those weeds produce most of their seeds post-harvest. The objectives of this study were to determine the ability of an optical sensor, installed for on-the-go measurement of grain protein concentration, to detect the presence of green plant matter in flowing grain and assess the potential usefulness of this information for mapping weeds at harvest. Spectra of the grain stream were recorded continuously at a rate of 0.33 Hz during harvest of two spring wheat fields of 1.9 and 5.4 ha. All readings were georeferenced using a Global Positioning System (GPS) receiver with 1 m positional accuracy. Chlorophyll of green plant matter was detectable in the red (638-710 nm) waveband. Maps of the chlorophyll signal from both fields showed an overall agreement of 78.1% with reference maps, one constructed prior to harvest and the other at harvest time, both based on visual evaluations of the three green weed species conducted by experts. Information on weed distributions at harvest may be useful for controlling post-harvest using variable rate technology for herbicide applications.

Optical Sensing of Weed Infestations at Harvest

PubMed Central

Barroso, Judit; McCallum, John; Long, Dan

2017-01-01

Kochia (Kochia scoparia L.), Russian thistle (Salsola tragus L.), and prickly lettuce (Lactuca serriola L.) are economically important weeds infesting dryland wheat (Triticum aestivum L.) production systems in the western United States. Those weeds produce most of their seeds post-harvest. The objectives of this study were to determine the ability of an optical sensor, installed for on-the-go measurement of grain protein concentration, to detect the presence of green plant matter in flowing grain and assess the potential usefulness of this information for mapping weeds at harvest. Spectra of the grain stream were recorded continuously at a rate of 0.33 Hz during harvest of two spring wheat fields of 1.9 and 5.4 ha. All readings were georeferenced using a Global Positioning System (GPS) receiver with 1 m positional accuracy. Chlorophyll of green plant matter was detectable in the red (638–710 nm) waveband. Maps of the chlorophyll signal from both fields showed an overall agreement of 78.1% with reference maps, one constructed prior to harvest and the other at harvest time, both based on visual evaluations of the three green weed species conducted by experts. Information on weed distributions at harvest may be useful for controlling post-harvest using variable rate technology for herbicide applications. PMID:29048342

Chloroplast Response to Low Leaf Water Potentials

PubMed Central

Boyer, J. S.; Potter, J. R.

1973-01-01

The effect of decreases in turgor on chloroplast activity was studied by measuring the photochemical activity of intact sunflower (Helianthus annuus L. cv. Russian Mammoth) leaves having low water potentials. Leaf turgor, calculated from leaf water potential and osmotic potential, was found to be affected by the dilution of cell contents by water in the cell walls, when osmotic potentials were measured with a thermocouple psychrometer. After the correction of measurements of leaf osmotic potential, both the thermocouple psychrometer and a pressure chamber indicated that turgor became zero in sunflower leaves at leaf water potentials of −10 bars. Since most of the loss in photochemical activity occurred at water potentials below −10 bars, it was concluded that turgor had little effect on the photochemical activity of the leaves. PMID:16658486

Temperature dependence of soil water potential

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mohamed, A.M.O.; Yong, R.N.; Cheung, S.C.H.

1992-12-01

To understand the process of coupled heat and water transport, the relationship between temperature and soil water potential must be known. Two clays, Avonlea bentonite and Lake Agassiz clay, are being considered as the clay-based sealing materials for the Canadian nuclear fuel waste disposal vault. Avonlea bentonite is distinguished from Lake Agassiz clay by its high sealing potential in water. A series of experiments was performed in which the two clays were mixed with equal amounts of sand and were compacted to a dry density of 1.67 Mg/m[sup 3] under various moisture contents and temperatures. A psychrometer was placed withinmore » the compacted clay-sand to measure the soil water potential based on the electromotive force measured by the psychrometer. The results indicate that the soil water potential at a particular temperature is higher for both clay-sand mixtures than predicted by the change in the surface tension of water; this effect is much more prominent in the Avonlea bentonite and at low moisture contents. The paper presents empirical equations relating the soil water potential with the moisture content and temperature of the two clay-sand mixtures. 24 refs., 8 figs., 2 tabs.« less

Harvest prediction in `Algerie' loquat

NASA Astrophysics Data System (ADS)

Hueso, Juan J.; Pérez, Mercedes; Alonso, Francisca; Cuevas, Julián

2007-05-01

Plant phenology is in great measure driven by air temperature. To forecast harvest time for ‘Algerie’ loquat accurately, the growing degree days (GDD) needed from bloom to ripening were determined using data from nine seasons. The methods proposed by Zalom et al. (Zalom FG, Goodell PB, Wilson LT, Barnett WW, Bentley W, Degree-days: the calculation and use of heat units in pest management, leaflet no 21373, Division Agriculture and Natural Resources, University of California 10 pp, 1983) were compared as regards their ability to estimate heat summation based on hourly records. All the methods gave remarkably similar results for our cultivation area, although the double-sine method showed higher performance when temperatures were low. A base temperature of 3°C is proposed for ‘Algerie’ loquat because it provides a coefficient of variation in GDD among seasons of below 5%, and because of its compatibility with loquat growth. Based on these determinations, ‘Algerie’ loquat requires 1,715 GDD from bloom to harvest; under our conditions this heat is accumulated over an average of 159 days. Our procedure permits the ‘Algerie’ harvest date to be estimated with a mean error of 4.4 days (<3% for the bloom-harvest period). GDD summation did not prove superior to the use of the number of calendar days for predicting ‘Algerie’ harvest under non-limiting growing conditions. However, GDD reflects the developmental rate in water-stressed trees better than calendar days. Trees under deficit irrigation during flower development required more time and more heat to ripen their fruits.

Harvest prediction in 'Algerie' loquat.

PubMed

Hueso, Juan J; Pérez, Mercedes; Alonso, Francisca; Cuevas, Julián

2007-05-01

Plant phenology is in great measure driven by air temperature. To forecast harvest time for 'Algerie' loquat accurately, the growing degree days (GDD) needed from bloom to ripening were determined using data from nine seasons. The methods proposed by Zalom et al. (Zalom FG, Goodell PB, Wilson LT, Barnett WW, Bentley W, Degree-days: the calculation and use of heat units in pest management, leaflet no 21373, Division Agriculture and Natural Resources, University of California 10 pp, 1983) were compared as regards their ability to estimate heat summation based on hourly records. All the methods gave remarkably similar results for our cultivation area, although the double-sine method showed higher performance when temperatures were low. A base temperature of 3 degrees C is proposed for 'Algerie' loquat because it provides a coefficient of variation in GDD among seasons of below 5%, and because of its compatibility with loquat growth. Based on these determinations, 'Algerie' loquat requires 1,715 GDD from bloom to harvest; under our conditions this heat is accumulated over an average of 159 days. Our procedure permits the 'Algerie' harvest date to be estimated with a mean error of 4.4 days (<3% for the bloom-harvest period). GDD summation did not prove superior to the use of the number of calendar days for predicting 'Algerie' harvest under non-limiting growing conditions. However, GDD reflects the developmental rate in water-stressed trees better than calendar days. Trees under deficit irrigation during flower development required more time and more heat to ripen their fruits.

Relationship of water potential to growth of leaves.

PubMed

Boyer, J S

1968-07-01

A thermocouple psychrometer that measures water potentials of intact leaves was used to study the water potentials at which leaves grow. Water potentials and water uptake during recovery from water deficits were measured simultaneously with leaves of sunflower (Helianthus annuus L.), tomato (Lycopersicon esculentum Mill.), papaya (Carica papaya L.), and Abutilon striatum Dickson. Recovery occurred in 2 phases. The first was associated with elimination of water deficits; the second with cell enlargement. The second phase was characterized by a steady rate of water uptake and a relatively constant leaf water potential. Enlargement was 70% irreversible and could be inhibited by puromycin and actinomycin D. During this time, leaves growing with their petioles in contact with pure water remained at a water potential of -1.5 to -2.5 bars regardless of the length of the experiment. It was not possible to obtain growing leaf tissue with a water potential of zero. It was concluded that leaves are not in equilibrium with the potential of the water which is absorbed during growth. The nonequilibrium is brought about by a resistance to water flow which requires a potential difference of 1.5 to 2.5 bars in order to supply water at the rate necessary for maximum growth.Leaf growth occurred in sunflower only when leaf water potentials were above -3.5 bars. Sunflower leaves therefore require a minimum turgor for enlargement, in this instance equivalent to a turgor of about 6.5 bars. The high water potentials required for growth favored rapid leaf growth at night and reduced growth during the day.

Flotation: A promising microalgae harvesting and dewatering technology for biofuels production.

PubMed

Ndikubwimana, Theoneste; Chang, Jingyu; Xiao, Zongyuan; Shao, Wenyao; Zeng, Xianhai; Ng, I-Son; Lu, Yinghua

2016-03-01

Microalgal biomass as renewable energy source is believed to be of great potential for reliable and sustainable biofuels production. However, microalgal biomass production is pinned by harvesting and dewatering stage thus hindering the developing and growing microalgae biotechnology industries. Flotation technology applied in mineral industry could be potentially applied in microalgae harvesting and dewatering, however substantial knowledge on different flotation units is essential. This paper presents an overview on different flotation units as promising cost-effective technologies for microalgae harvesting thus bestowing for further research in development and commercialization of microalgae based biofuels. Dispersed air flotation was found to be less energy consuming. Moreover, Jameson cell flotation and dispersed ozone flotation are believed to be energy efficient microalgae flotation approaches. Microalgae harvesting and dewatering by flotation is still at embryonic stage, therefore extended studies with the focus on life cycle assessment, sustainability of the flotation unit, optimization of the operating parameters using different algal species is imperative. Though there are a number of challenges in microalgae harvesting and dewatering, with well designed and developed cultivation, harvesting/dewatering, extraction and conversion technologies, progressively, microalgae technology will be of great potential for biological carbon sequestration, biofuels and biochemicals production. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Statistical-QoS Guaranteed Energy Efficiency Optimization for Energy Harvesting Wireless Sensor Networks.

PubMed

Gao, Ya; Cheng, Wenchi; Zhang, Hailin

2017-08-23

Energy harvesting, which offers a never-ending energy supply, has emerged as a prominent technology to prolong the lifetime and reduce costs for the battery-powered wireless sensor networks. However, how to improve the energy efficiency while guaranteeing the quality of service (QoS) for energy harvesting based wireless sensor networks is still an open problem. In this paper, we develop statistical delay-bounded QoS-driven power control policies to maximize the effective energy efficiency (EEE), which is defined as the spectrum efficiency under given specified QoS constraints per unit harvested energy, for energy harvesting based wireless sensor networks. For the battery-infinite wireless sensor networks, our developed QoS-driven power control policy converges to the Energy harvesting Water Filling (E-WF) scheme and the Energy harvesting Channel Inversion (E-CI) scheme under the very loose and stringent QoS constraints, respectively. For the battery-finite wireless sensor networks, our developed QoS-driven power control policy becomes the Truncated energy harvesting Water Filling (T-WF) scheme and the Truncated energy harvesting Channel Inversion (T-CI) scheme under the very loose and stringent QoS constraints, respectively. Furthermore, we evaluate the outage probabilities to theoretically analyze the performance of our developed QoS-driven power control policies. The obtained numerical results validate our analysis and show that our developed optimal power control policies can optimize the EEE over energy harvesting based wireless sensor networks.

Statistical-QoS Guaranteed Energy Efficiency Optimization for Energy Harvesting Wireless Sensor Networks

PubMed Central

Cheng, Wenchi; Zhang, Hailin

2017-01-01

Energy harvesting, which offers a never-ending energy supply, has emerged as a prominent technology to prolong the lifetime and reduce costs for the battery-powered wireless sensor networks. However, how to improve the energy efficiency while guaranteeing the quality of service (QoS) for energy harvesting based wireless sensor networks is still an open problem. In this paper, we develop statistical delay-bounded QoS-driven power control policies to maximize the effective energy efficiency (EEE), which is defined as the spectrum efficiency under given specified QoS constraints per unit harvested energy, for energy harvesting based wireless sensor networks. For the battery-infinite wireless sensor networks, our developed QoS-driven power control policy converges to the Energy harvesting Water Filling (E-WF) scheme and the Energy harvesting Channel Inversion (E-CI) scheme under the very loose and stringent QoS constraints, respectively. For the battery-finite wireless sensor networks, our developed QoS-driven power control policy becomes the Truncated energy harvesting Water Filling (T-WF) scheme and the Truncated energy harvesting Channel Inversion (T-CI) scheme under the very loose and stringent QoS constraints, respectively. Furthermore, we evaluate the outage probabilities to theoretically analyze the performance of our developed QoS-driven power control policies. The obtained numerical results validate our analysis and show that our developed optimal power control policies can optimize the EEE over energy harvesting based wireless sensor networks. PMID:28832509

A novel method to harvest Chlorella sp. by co-flocculation/air flotation.

PubMed

Zhang, Haiyang; Lin, Zhe; Tan, Daoyong; Liu, Chunhua; Kuang, Yali; Li, Zhu

2017-01-01

To develop a more effective dissolved air flotation process for harvesting microalgae biomass, a co-flocculation/air flotation (CAF) system was developed that uses an ejector followed by a helix tube flocculation reactor (HTFR) as a co-flocculation device to harvest Chlorella sp. 64.01. The optimal size distribution of micro-bubbles and an air release efficiency of 96 % were obtained when the flow ratio of inlet fluid (raw water) to motive fluid (saturated water) of the ejector was 0.14. With a reaction time of 24 s in the HTFR, microalgae cells and micro-bubbles were well flocculated, and these aerated flocs caused a fast rising velocity (96 m/h) and high harvesting efficiency (94 %). In a CAF process, micro-bubbles can be encapsulated into microalgae flocs, which makes aerated flocs more stable. CAF is an effective approach to harvesting microalgae.

Reducing electrocoagulation harvesting costs for practical microalgal biodiesel production.

PubMed

Dassey, Adam J; Theegala, Chandra S

2014-01-01

Electrocoagulation has shown potential to be a primary microalgae harvesting technique for biodiesel production. However, methods to reduce energy and electrode costs are still necessary for practical application. Electrocoagulation tests were conducted on Nannochloris sp. and Dunaliella sp. using perforated aluminium and iron electrodes under various charge densities. Aluminium electrodes were shown to be more efficient than iron electrodes when harvesting both algal species. Despite the lower harvesting efficiency, however, the iron electrodes were more energy and cost efficient. Operational costs of less than $0.03/L oil were achieved when harvesting Nannochloris sp. with iron electrodes at 35% harvest efficiency, whereas aluminium electrodes cost $0.75/L oil with 42% harvesting efficiency. Increasing the harvesting efficiencies for both aluminium and iron electrodes also increased the overall cost per litre of oil, therefore lower harvesting efficiencies with lower energy inputs was recommended. Also, increasing the culturing salinity to 2 ppt sodium chloride for freshwater Nannochloris sp. was determined practical to improve the electrocoagulation energy efficiency despite a 25% reduction in cell growth.

Electrostrictive Polymers for Mechanical-to-Electrical Energy Harvesting

DTIC Science & Technology

usable electrical energy. Piezoelectric ceramic-based devices have long been used in energy harvesting for converting mechanical motion to electrical ...typically softer and more flexible, the translated electrical energy output is considerably higher under the same mechanical force. Currently...investigations in using electroactive polymers for energy harvesting, and mechanical-to- electrical energy conversion, are beginning to show potential for

The Potential for Harvesting Energy from the Movement of Trees

PubMed Central

McGarry, Scott; Knight, Chris

2011-01-01

Over the last decade, wireless devices have decreased in size and power requirements. These devices generally use batteries as a power source but can employ additional means of power, such as solar, thermal or wind energy. However, sensor networks are often deployed in conditions of minimal lighting and thermal gradient such as densely wooded environments, where even normal wind energy harvesting is limited. In these cases a possible source of energy is from the motion of the trees themselves. We investigated the amount of energy and power available from the motion of a tree in a sheltered position, during Beaufort 4 winds. We measured the work performed by the tree to lift a mass, we measured horizontal acceleration of free movement, and we determined the angular deflection of the movement of the tree trunk, to determine the energy and power available to various types of harvesting devices. We found that the amount of power available from the tree, as demonstrated by lifting a mass, compares favourably with the power required to run a wireless sensor node. PMID:22163695

The potential for harvesting energy from the movement of trees.

PubMed

McGarry, Scott; Knight, Chris

2011-01-01

Over the last decade, wireless devices have decreased in size and power requirements. These devices generally use batteries as a power source but can employ additional means of power, such as solar, thermal or wind energy. However, sensor networks are often deployed in conditions of minimal lighting and thermal gradient such as densely wooded environments, where even normal wind energy harvesting is limited. In these cases a possible source of energy is from the motion of the trees themselves. We investigated the amount of energy and power available from the motion of a tree in a sheltered position, during Beaufort 4 winds. We measured the work performed by the tree to lift a mass, we measured horizontal acceleration of free movement, and we determined the angular deflection of the movement of the tree trunk, to determine the energy and power available to various types of harvesting devices. We found that the amount of power available from the tree, as demonstrated by lifting a mass, compares favourably with the power required to run a wireless sensor node.

Wastewater polishing by a channelized macrophyte-dominated wetland and anaerobic digestion of the harvested phytomass.

PubMed

Cohen, Michael F; Hare, Caden; Kozlowski, John; McCormick, Rachel S; Chen, Lily; Schneider, Linden; Parish, Meghan; Knight, Zane; Nelson, Timothy A; Grewell, Brenda J

2013-01-01

Constructed wetlands (CW) offer a mechanism to meet increasingly stringent regulatory standards for wastewater treatment while minimizing energy inputs. Additionally, harvested wetland phytomass subjected to anaerobic digestion can serve as a source of biogas methane. To investigate CW wastewater polishing activities and potential energy yield we constructed a pair of secondary wastewater-fed channelized CW modules designed to retain easily harvestable floating aquatic vegetation and maximize exposure of water to roots and sediment. Modules that were regularly harvested averaged a nitrate removal rate of 1.1 g N m(-2) d(-1); harvesting, sedimentation and gasification were responsible for 30.5%, 8.0% and 61.5% of the N losses, respectively. Selective harvesting of a module to maintain dominance of filamentous algae had no effect on nitrate removal rate but lowered productivity by one-half. The average monthly productivity for unselectively harvested modules was 9.3 ± 1.7 g dry wt. m(-2) d(-1) (±SE). Cessation of harvesting in one module resulted in a significant increase in nitrate removal rate and decrease in phosphate removal rate. Compared to the influent, the effluent of the harvested module had significantly lower levels of estrogenic activity, as determined by a quantitative PCR-based juvenile trout bioassay, and significantly lower densities of E. coli. In mixed vertical-flow reactors anaerobic co-digestion of equal dry weight proportions of harvested aquatic vegetation, wine yeast lees and dairy manure was greatly improved when the manure was replaced with the crude glycerol by-product of biodiesel production. Remaining solids were vermicomposted for use as a soil amendment. Our results indicate that incorporation of constructed wetlands into an integrated treatment system can simultaneously enhance the economic and energetic feasibility of wastewater and organic waste treatment processes.

Miscellaneous methods for measuring matric or water potential

USGS Publications Warehouse

Scanlon, Bridget R.; Andraski, Brian J.; Bilskie, Jim; Dane, Jacob H.; Topp, G. Clarke

2002-01-01

A variety of techniques to measure matric potential or water potential in the laboratory and in the field are described in this section. The techniques described herein require equilibration of some medium whose matric or water potential can be determined from previous calibration or can be measured directly. Under equilibrium conditions the matric or water potential of the medium is equal to that of the soil. The techniques can be divided into: (i) those that measure matric potential and (ii) those that measure water potential (sum of matric and osmotic potentials). Matric potential is determined when the sensor matrix is in direct contact with the soil, so salts are free to diffuse in or out of the sensor matrix, and the equilibrium measurement therefore reflects matric forces acting on the water. Water potential is determined when the sensor is separated from the soil by a vapor gap, so salts are not free to move in or out of the sensor, and the equilibrium measurement reflects the sum of the matric and osmotic forces acting on the water.Seven different techniques are described in this section. Those that measure matric potential include (i) heat dissipation sensors, (ii) electrical resistance sensors, (iii) frequency domain and time domain sensors, and (iv) electro-optical switches. A method that can be used to measure matric potential or water potential is the (v) filter paper method. Techniques that measure water potential include (vi) the Dew Point Potentiameter (Decagon Devices, Inc., Pullman, WA1) (water activity meter) and (vii) vapor equilibration.The first four techniques are electronically based methods for measuring matric potential. Heat dissipation sensors and electrical resistance sensors infer matric potential from previously determined calibration relations between sensor heat dissipation or electrical resistance and matric potential. Frequency-domain and timedomain matric potential sensors measure water content, which is related to matric

Energy harvesting for human wearable and implantable bio-sensors.

PubMed

Mitcheson, Paul D

2010-01-01

There are clear trade-offs between functionality, battery lifetime and battery volume for wearable and implantable wireless-biosensors which energy harvesting devices may be able to overcome. Reliable energy harvesting has now become a reality for machine condition monitoring and is finding applications in chemical process plants, refineries and water treatment works. However, practical miniature devices that can harvest sufficient energy from the human body to power a wireless bio-sensor are still in their infancy. This paper reviews the options for human energy harvesting in order to determine power availability for harvester-powered body sensor networks. The main competing technologies for energy harvesting from the human body are inertial kinetic energy harvesting devices and thermoelectric devices. These devices are advantageous to some other types as they can be hermetically sealed. In this paper the fundamental limit to the power output of these devices is compared as a function of generator volume when attached to a human whilst walking and running. It is shown that the kinetic energy devices have the highest fundamental power limits in both cases. However, when a comparison is made between the devices using device effectivenesses figures from previously demonstrated prototypes presented in the literature, the thermal device is competitive with the kinetic energy harvesting device when the subject is running and achieves the highest power density when the subject is walking.

A seesaw-type approach for enhancing nonlinear energy harvesting

NASA Astrophysics Data System (ADS)

Deng, Huaxia; Wang, Zhemin; Du, Yu; Zhang, Jin; Ma, Mengchao; Zhong, Xiang

2018-05-01

Harvesting sustainable mechanical energy is the ultimate objective of nonlinear energy harvesters. However, overcoming potential barriers, especially without the use of extra excitations, poses a great challenge for the development of nonlinear generators. In contrast to the existing methods, which typically modify the barrier height or utilize additional excitations, this letter proposes a seesaw-type approach to facilitate escape from potential wells by transfer of internal energy, even under low-intensity excitation. This approach is adopted in the design of a seesaw-type nonlinear piezoelectric energy harvester and the energy transfer process is analyzed by deriving expressions for the energy to reveal the working mechanism. Comparison experiments demonstrate that this approach improves energy harvesting in terms of an increase in the working frequency bandwidth by a factor of 60.14 and an increase in the maximum output voltage by a factor of 5.1. Moreover, the output power is increased by a factor of 51.3, which indicates that this approach significantly improves energy collection efficiency. This seesaw-type approach provides a welcome boost to the development of renewable energy collection methods by improving the efficiency of harvesting of low-intensity ambient mechanical energy.

Carbon isotope discrimination and water stress in trembling aspen following variable retention harvesting.

PubMed

Bladon, Kevin D; Silins, Uldis; Landhäusser, Simon M; Messier, Christian; Lieffers, Victor J

2007-07-01

Variable retention harvesting (VRH) has been proposed as a silvicultural practice to maintain biodiversity and ecosystem integrity. No previous study has examined tree carbon isotope discrimination to provide insights into water stress that could lead to dieback and mortality of trees following VRH. We measured and compared the carbon isotope ratios (delta(13)C) in stem wood of trembling aspen (Populus tremuloides Michx.) before and after VRH. Eight trees were sampled from isolated residual, edge and control (interior of unharvested stand) positions from each of seven plots in three regions (Calling Lake and Drayton Valley, Alberta and Lac Duparquet, Québec). After VRH, the general trend in mean delta(13)C was residual > edge > control trees. Although this trend is indicative of water stress in residual trees, it also suggests that edge trees received some sheltering effect, reducing their stress compared with that of residuals. A strong inverse relationship was found between the delta(13)C values and the mean annual precipitation in each region. The trend in mean delta(13)C signature was Calling Lake > Drayton Valley > Lac Duparquet trees. These results suggest that residual or edge trees in drier regions are more likely to suffer water stress following VRH. We also observed a trend of greater delta(13)C in stout trees compared with slender trees, both before and after VRH. The evidence of greater water stress in stout trees likely occurred because of a positive relationship between stem diameter and crown volume per basal area. Our results provide evidence that water stress could be the driving mechanism leading to dieback and mortality of residual trees shortly after VRH. Additionally, the results from edge trees indicate that leaving hardwood residuals in larger patches or more sheltered landscape positions could reduce the water stress to which these trees are subjected, thereby reducing dieback and mortality.

Review of the harvesting and extraction of advanced biofuels and bioproducts

Treesearch

Babette L. Marrone;  Ronald E.  Lacey;  Daniel B. Anderson;  James Bonner;  Jim Coons;  Taraka Dale;  Cara Meghan Downes;  Sandun Fernando;  Christopher  Fuller;  Brian Goodall;  Johnathan E. Holladay;  Kiran Kadam;  Daniel  Kalb;  Wei  Liu;  John B. Mott;  Zivko Nikolov;  Kimberly L. Ogden;  Richard T. Sayre;  Brian G. Trewyn;  José A. Olivares

2017-01-01

Energy-efficient and scalable harvesting and lipid extraction processes must be developed in order for the algal biofuels and bioproducts industry to thrive. The major challenge for harvesting is the handling of large volumes of cultivation water to concentrate low amounts of biomass. For lipid extraction, the major energy and cost drivers are associated with...

Implementation of a piezoelectric energy harvester in railway health monitoring

NASA Astrophysics Data System (ADS)

Li, Jingcheng; Jang, Shinae; Tang, Jiong

2014-03-01

With development of wireless sensor technology, wireless sensor network has shown a great potential for railway health monitoring. However, how to supply continuous power to the wireless sensor nodes is one of the critical issues in long-term full-scale deployment of the wireless smart sensors. Some energy harvesting methodologies have been available including solar, vibration, wind, etc; among them, vibration-based energy harvester using piezoelectric material showed the potential for converting ambient vibration energy to electric energy in railway health monitoring even for underground subway systems. However, the piezoelectric energy harvester has two major problems including that it could only generate small amount of energy, and that it should match the exact narrow band natural frequency with the excitation frequency. To overcome these problems, a wide band piezoelectric energy harvester, which could generate more power on various frequencies regions, has been designed and validated with experimental test. Then it was applied to a full-scale field test using actual railway train. The power generation of the wide band piezoelectric array has been compared to a narrow-band, resonant-based, piezoelectric energy harvester.

An energy-harvesting power supply for underwater bridge scour monitoring sensors

NASA Astrophysics Data System (ADS)

Wang, Yuli; Li, Yingjie; He, Longzhuang; Shamsi, Pourya; Zheng, Yahong R.

2018-03-01

The natural force of scouring has become one of the most critical risk endangering the endurance of bridges, thus leading to the necessity of deploying underwater monitoring sensors to actively detect potential scour holes under bridges. Due to the difficulty in re-charging batteries for underwater sensors, super capacitors with energy harvesting (EH) means are exploited to prolong the sustainability of underwater sensors. In this paper, an energy harvesting power supply based on a helical turbine is proposed to power underwater monitoring sensors. A small helical turbine is designed to convert water flow energy to electrical energy with favorable environmental robustness. A 3-inch diameter, 2.5-inch length and 3-bladed helical turbine was designed with two types of waterproof coupling with the sensor housing. Both designs were prototyped and tested under different flow conditions and we get valid voltage around 0.91 V which is enough to power monitoring sensor. The alternating current (AC) electrical energy generated by the helical turbine is then rectified and boosted to drive a DC charger for efficiently charging one super capacitor. The charging circuit was designed, prototyped and tested thoroughly with the helical turbine harvester. The results were promising, that the overall power supply can power an underwater sensor node with wireless transceivers for long-term operations

Chronic Wasting Disease: Transmission Mechanisms and the Possibility of Harvest Management

PubMed Central

Potapov, Alex; Merrill, Evelyn; Pybus, Margo; Lewis, Mark A.

2016-01-01

We develop a model of CWD management by nonselective deer harvest, currently the most feasible approach available for managing CWD in wild populations. We use the model to explore the effects of 6 common harvest strategies on disease prevalence and to identify potential optimal harvest policies for reducing disease prevalence without population collapse. The model includes 4 deer categories (juveniles, adult females, younger adult males, older adult males) that may be harvested at different rates, a food-based carrying capacity, which influences juvenile survival but not adult reproduction or survival, and seasonal force of infection terms for each deer category under differing frequency-dependent transmission dynamics resulting from environmental and direct contact mechanisms. Numerical experiments show that the interval of transmission coefficients β where the disease can be controlled is generally narrow and efficiency of a harvest policy to reduce disease prevalence depends crucially on the details of the disease transmission mechanism, in particular on the intensity of disease transmission to juveniles and the potential differences in the behavior of older and younger males that influence contact rates. Optimal harvest policy to minimize disease prevalence for each of the assumed transmission mechanisms is shown to depend on harvest intensity. Across mechanisms, a harvest that focuses on antlered deer, without distinguishing between age classes reduces disease prevalence most consistently, whereas distinguishing between young and older antlered deer produces higher uncertainty in the harvest effects on disease prevalence. Our results show that, despite uncertainties, a modelling approach can determine classes of harvest strategy that are most likely to be effective in combatting CWD. PMID:26963921

Evaluation of modern cotton harvest systems on irrigated cotton: harvester performance

USDA-ARS?s Scientific Manuscript database

Picker and stripper harvest systems were evaluated on production-scale irrigated cotton on the High Plains of Texas over three harvest seasons. Observations on harvester performance, including time-in-motion, harvest loss, seed cotton composition, and turnout, were conducted at seven locations with...

Measuring water potential (activity) from free water to oven dryness.

PubMed

Wiebe, H H

1981-12-01

Water activities (potentials) in plant materials were measured over the range from free water to oven dryness with a Spanner thermocouple psychrometer. In a two-step procedure, water was first condensed on the thermocouple junction for several minutes. The sample was then inserted under the wet thermocouple and the maximum psychrometric cooling was measured in about 10 seconds. Calibration was with saturated salt slurries of known water activities. Psychrometric cooling was a nearly linear function of the water activity and of the negative log of the water potential. The psychrometric cooling to water activity relationship agreed with wetbulb temperature depression to relative humidity relationships given in tables. Water activities of wheat grains and leaves decreased sharply in a curvilinear fashion as their water contents decreased. Some problems of the procedure are discussed.

Corn stover harvest increases herbicide movement to subsurface drains - Root Zone Water Quality Model simulations.

PubMed

Shipitalo, Martin J; Malone, Robert W; Ma, Liwang; Nolan, Bernard T; Kanwar, Rameshwar S; Shaner, Dale L; Pederson, Carl H

2016-06-01

Crop residue removal for bioenergy production can alter soil hydrologic properties and the movement of agrochemicals to subsurface drains. The Root Zone Water Quality Model (RZWQM), previously calibrated using measured flow and atrazine concentrations in drainage from a 0.4 ha chisel-tilled plot, was used to investigate effects of 50 and 100% corn (Zea mays L.) stover harvest and the accompanying reductions in soil crust hydraulic conductivity and total macroporosity on transport of atrazine, metolachlor and metolachlor oxanilic acid (OXA). The model accurately simulated field-measured metolachlor transport in drainage. A 3 year simulation indicated that 50% residue removal reduced subsurface drainage by 31% and increased atrazine and metolachlor transport in drainage 4-5-fold when surface crust conductivity and macroporosity were reduced by 25%. Based on its measured sorption coefficient, approximately twofold reductions in OXA losses were simulated with residue removal. The RZWQM indicated that, if corn stover harvest reduces crust conductivity and soil macroporosity, losses of atrazine and metolachlor in subsurface drainage will increase owing to reduced sorption related to more water moving through fewer macropores. Losses of the metolachlor degradation product OXA will decrease as a result of the more rapid movement of the parent compound into the soil. Published 2015. This article is a U.S. Government work and is in the public domain in the USA. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

Expansion and Harvesting of hMSC-TERT

PubMed Central

Weber, Christian; Pohl, Sebastian; Pörtner, Ralf; Wallrapp, Christine; Kassem, Moustapha; Geigle, Peter; Czermak, Peter

2007-01-01

The expansion of human mesenchymal stem cells as suspension culture by means of spinner flasks and microcarriers, compared to the cultivation in tissue culture flasks, offers the advantage of reducing the requirements of large incubator capacities as well as reducing the handling effort during cultivation and harvesting. Nonporous microcarriers are preferable when the cells need to be kept in viable condition for further applications like tissue engineering or cell therapy. In this study, the qualification of Biosilon, Cytodex 1, Cytodex 3, RapidCell and P102-L for expansion of hMSC-TERT with an associated harvesting process using either trypsin, accutase, collagenase or a trypsin-accutase mixture was investigated. A subsequent adipogenic differentiation of harvested hMSC-TERT was performed in order to observe possible negative effects on their (adipogenic) differentiation potential as a result of the cultivation and harvesting method. The cultivated cells showed an average growth rate of 0.52 d-1. The cells cultivated on Biosilon, RapidCell and P102-L were harvested succesfully achieving high cell yield and vitalities near 100%. This was not the case for cells on Cytodex 1 and Cytodex 3. The trypsin-accutase mix was most effective. After spinner expansion and harvesting the cells were successfully differentiated to adipocytes. PMID:19662126

Understanding how surface chemistry and topography enhance fog harvesting based on the superwetting surface with patterned hemispherical bulges.

PubMed

Zhong, Lieshuang; Zhu, Hai; Wu, Yang; Guo, Zhiguang

2018-09-01

The Namib Desert beetle-Stenocara can adapt to the arid environment by its fog harvesting ability. A series of samples with different topography and wettability that mimicked the elytra of the beetle were fabricated to study the effect of these factors on fog harvesting. The superhydrophobic bulgy sample harvested 1.5 times the amount of water than the sample with combinational pattern of hydrophilic bulgy/superhydrophobic surrounding and 2.83 times than the superhydrophobic surface without bulge. These bulges focused the droplets around them which endowed droplets with higher velocity and induced the highest dynamic pressure atop them. Superhydrophobicity was beneficial for the departure of harvested water on the surface of sample. The bulgy topography, together with surface wettability, dominated the process of water supply and water removal. Copyright © 2018 Elsevier Inc. All rights reserved.

Piezo-Electrochemical Energy Harvesting with Lithium-Intercalating Carbon Fibers.

PubMed

Jacques, Eric; Lindbergh, Göran; Zenkert, Dan; Leijonmarck, Simon; Kjell, Maria Hellqvist

2015-07-01

The mechanical and electrochemical properties are coupled through a piezo-electrochemical effect in Li-intercalated carbon fibers. It is demonstrated that this piezo-electrochemical effect makes it possible to harvest electrical energy from mechanical work. Continuous polyacrylonitrile-based carbon fibers that can work both as electrodes for Li-ion batteries and structural reinforcement for composites materials are used in this study. Applying a tensile force to carbon fiber bundles used as Li-intercalating electrodes results in a response of the electrode potential of a few millivolts which allows, at low current densities, lithiation at higher electrode potential than delithiation. More electrical energy is thereby released from the cell at discharge than provided at charge, harvesting energy from the mechanical work of the applied force. The measured harvested specific electrical power is in the order of 1 μW/g for current densities in the order of 1 mA/g, but this has a potential of being increased significantly.

The Impacts of Water Conservation Strategies on Water Use: Four Case Studies.

PubMed

Tsai, Yushiou; Cohen, Sara; Vogel, Richard M

2011-08-01

We assessed impacts on water use achieved by implementation of controlled experiments relating to four water conservation strategies in four towns within the Ipswich watershed in Massachusetts. The strategies included (1) installation of weather-sensitive irrigation controller switches (WSICS) in residences and municipal athletic fields; (2) installation of rainwater harvesting systems in residences; (3) two outreach programs: (a) free home indoor water use audits and water fixture retrofit kits and (b) rebates for low-water-demand toilets and washing machines; and (4) soil amendments to improve soil moisture retention at a municipal athletic field. The goals of this study are to summarize the effectiveness of the four water conservation strategies and to introduce nonparametric statistical methods for evaluating the effectiveness of these conservation strategies in reducing water use. It was found that (1) the municipal WSICS significantly reduced water use; (2) residences with high irrigation demand were more likely than low water users to experience a substantial demand decrease when equipped with the WSICS; (3) rainwater harvesting provided substantial rainwater use, but these volumes were small relative to total domestic water use and relative to the natural fluctuations in domestic water use; (4) both the audits/retrofit and rebate programs resulted in significant water savings; and (5) a modeling approach showed potential water savings from soil amendments in ball fields.

Effects of forest harvest on biogeochemical processes in the Caspar Creek watershed

Treesearch

Randy A. Dahlgren

1998-01-01

Water quality and long-term sustainability are major components addressed within the ecosystem approach to forest management. Forest harvest practices are often implicated as having adverse impacts on sensitive aquatic communities and on the long-term sustainability of forest ecosystems. While careless harvest practices can certainly cause adverse impacts, proper...

Water-quality assessment of the Smith River drainage basin, California and Oregon

USGS Publications Warehouse

Iwatsubo, Rick T.; Washabaugh, Donna S.

1982-01-01

A water-quality assessment of the Smith River drainage basin was made to provide a summary of the water-quality conditions including known or potential water-quality problems. Results of the study showed that the water quality of the Smith River is excellent and generally meets the water-quality objectives for the beneficial uses identified by the California Regional Water Quality Control Board, North Coast Region. Known and potential problems related to water quality include: Sedimentation resulting from both natural erosional processes and land-use activities such as timber harvest, road construction, and mining that accelerate the erosional processes; bacterial contamination of surface and ground waters from inundated septic tanks and drainfields, and grazing activities; industrial spills which have resulted in fish kills and oil residues; high concetrations of iron in ground water; log and debris jams creating fish migration barriers; and pesticide and trace-element contamination from timber-harvest and mining activities, respectively. Future studies are needed to establish: (1) a sustained long-term monitoring program to provide a broad coverage of water-quality conditions in order to define long-term water-quality trends; and (2) interpretive studies to determine the source of known and potential water-quality problems. (USGS)

50 CFR 640.21 - Harvest limitations.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., DEPARTMENT OF COMMERCE SPINY LOBSTER FISHERY OF THE GULF OF MEXICO AND SOUTH ATLANTIC Management Measures § 640.21 Harvest limitations. (a) Berried lobsters. A berried (egg-bearing) spiny lobster or slipper lobster in or from the EEZ must be returned immediately to the water unharmed. If found in a trap in the...

50 CFR 640.21 - Harvest limitations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... ADMINISTRATION, DEPARTMENT OF COMMERCE SPINY LOBSTER FISHERY OF THE GULF OF MEXICO AND SOUTH ATLANTIC Management Measures § 640.21 Harvest limitations. (a) Berried lobsters. A berried (egg-bearing) spiny lobster or slipper lobster in or from the EEZ must be returned immediately to the water unharmed. If found in a trap...

Harvesting considerations for ecosystem restoration projects

Treesearch

Dana Mitchell; John Klepac

2014-01-01

There is a need to identify and develop cost effective harvesting systems for ecosystem restoration projects. In the Western United States, pinyon-juniper woodlands are expanding into sagebrush and rangeland ecosystems. In many areas, this growth negatively impacts water, wildlife habitat, biodiversity, and other resources. In other areas, such as Texas and Oklahoma,...

Fog harvesting on the verge of economic competitiveness

NASA Astrophysics Data System (ADS)

Tiedemann, K. J.; Lummerich, A.

2010-07-01

Water scarcity is the bottleneck for agriculture and development of Peru’s coast and subject to aggravation due to climate change. Until present day, Peru’s coast in general and the Lima Metropolitan Area (LMA) in particular have enjoyed to a great extend the effect of the country’s high altitude glaciers that serve as a buffer for the capital’s water demand during the highland dry season. However, climate models predict the disappearance of this buffer system below 5.500 masl by 2015, leaving one of the driest places on earth with yet another decrease in freshwater supply (Zapata 2008). The deviation of water resources from the highlands has led already to allocation conflicts. Peru is in urgent need of new concepts for water management. Fog harvesting was introduced to South America in the 1980s and has since been implemented at various locations in North and Central America, Europe, Africa, Asia and Australia. The Standard Fog Collector (SFC) as described by Schemenauer and Cereceda (1994) has proven to be a successful instrument for this purpose. Apart from a number of small scale investigations, the design of the collector has barely been changed over the past three decades (e.g. Gioda et al. 1993). Within the framework of the presented project, financed primarily by the Global Exploration Fund of the National Geographic Society and Bayer AG, new fog collectors were designed at pilot and full scale. Best results in terms of simplicity of construction and water yield were obtained by a metal frame structure called Eiffel. While covering the same amount of space as an SFC and using the same Raschel 65% shadow net, the Eiffel collector harvested up to 2.650 liters of water within a frame of 8x4m compared to up to 600 liters of water harvested by a SFC at the same location. In combination with a simplified maintenance concept, our collectors present an economically competitive alternative to water supply by truck delivery in a region that is not likely to

Hybrid energy harvesting/transmission system for embedded devices

NASA Astrophysics Data System (ADS)

Hehr, Adam; Park, Gyuhae; Farinholt, Kevin

2012-04-01

In most energy harvesting applications the need for a reliable long-term energy supply is essential in powering embedded sensing and control electronics. The goal of many harvesters is to extract energy from the ambient environment to power hardware; however in some applications there may be conditions in which the harvester's performance cannot meet all of the demands of the embedded electronics. One method for addressing this shortfall is to supplement harvested power through the transmission of wireless energy, a concept that has successfully been demonstrated by the authors in previous studies. In this paper we present our findings on the use of a single electromagnetic coil to harvest kinetic energy in a solenoid configuration, as well as background and directed wireless energy in the 2.4 GHz radio frequency (RF) bands commonly used in WiFi and cellular phone applications. The motivation for this study is to develop a compact energy harvester / receiver that conserves physical volume, while providing multi-modal energy harvesting capabilities. As with most hybrid systems there are performance trade-offs that must be considered when capturing energy from different physical sources. As part of this paper, many of the issues related to power transmission, physical design, and potential applications are addressed for this device.

Floating microbial fuel cells as energy harvesters for signal transmission from natural water bodies

NASA Astrophysics Data System (ADS)

Schievano, Andrea; Colombo, Alessandra; Grattieri, Matteo; Trasatti, Stefano P.; Liberale, Alessandro; Tremolada, Paolo; Pino, Claudio; Cristiani, Pierangela

2017-02-01

A new type of floating microbial fuel cell (fMFC) was developed for power supply of remote environmental sensors and data transmission. Ten operating fMFCs generated a cell potential in the range 100-800 mV depending on the external resistance applied. Power production peaked around 3-3.5 mW (power density of 22-28 mW m-2 cathode) after about 20-30 days of start-up period. The average of daily electrical energy harvested ranged between 10 and 35 mWh/d. Long-term performances were ensured in the presence of dense rice plants (Oryza Sativa). A power management system, based on a step-up DC/DC converter and a low-power data transmission system via SIGFOX™ technology, have been set up for the fMFCs. The tested fMFCs systems allowed to: i) harvest produced energy, ii) supply electronic devices (intermittent LED-light and a buzzer); iii) transmit remote data at low speed (three message of 12 bites each, in 6 s). Several 'floating garden' MFCs were set in the context of demonstrative events at EXPO2015 world exposition held in Milan between May-October 2015. Some of the 'floating garden' MFCs were operating for more than one year.

Harvesting

USDA-ARS?s Scientific Manuscript database

The spindle picker and brush-roll stripper are the two machines used to harvest cotton produced in the United States. Adoption of each harvester type is dictated by regional differences in regard to production environment, production practices, cultivar, and yield. The spindle picker is a selectiv...

Liquid-Desiccant Vapor Separation Reduces the Energy Requirements of Atmospheric Moisture Harvesting.

PubMed

Gido, Ben; Friedler, Eran; Broday, David M

2016-08-02

An innovative atmospheric moisture harvesting system is proposed, where water vapor is separated from the air prior to cooling and condensation. The system was studied using a model that simulates its three interconnected cycles (air, desiccant, and water) over a range of ambient conditions, and optimal configurations are reported for different operation conditions. Model results were compared to specifications of commercial atmospheric moisture harvesting systems and found to represent saving of 5-65% of the electrical energy requirements due to the vapor separation process. We show that the liquid desiccant separation stage that is integrated into atmospheric moisture harvesting systems can work under a wide range of environmental conditions using low grade or solar heating as a supplementary energy source, and that the performance of the combined system is superior.

Grassland bird response to harvesting switchgrass as a biomass energy crop

USGS Publications Warehouse

Roth, A.M.; Sample, D.W.; Ribic, C.A.; Paine, L.; Undersander, D.J.; Bartelt, G.A.

2005-01-01

The combustion of perennial grass biomass to generate electricity may be a promising renewable energy option. Switchgrass (Panicum virgatum) grown as a biofuel has the potential to provide a cash crop for farmers and quality nesting cover for grassland birds. In southwestern Wisconsin (near lat. 42??52???, long. 90??08???), we investigated the impact of an August harvest of switchgrass for bioenergy on community composition and abundance of Wisconsin grassland bird species of management concern. Harvesting the switchgrass in August resulted in changes in vegetation structure and bird species composition the following nesting season. In harvested transects, residual vegetation was shorter and the litter layer was reduced in the year following harvest. Grassland bird species that preferred vegetation of short to moderate height and low to moderate density were found in harvested areas. Unharvested areas provided tall, dense vegetation structure that was especially attractive to tall-grass bird species, such as sedge wren (Cistothorus platensis) and Henslow's sparrow (Ammodramus henslowii). When considering wildlife habitat value in harvest management of switchgrass for biofuel, leaving some fields unharvested each year would be a good compromise, providing some habitat for a larger number of grassland bird species of management concern than if all fields were harvested annually. In areas where most idle grassland habitat present on the landscape is tallgrass, harvest of switchgrass for biofuel has the potential to increase the local diversity of grassland birds.

Fundamentals in Microalgae Harvesting: From Flocculation to Self-attachment

NASA Astrophysics Data System (ADS)

Cui, Yan

Microalgae are a very promising source of biodiesel and other renewable energy due to their fast grow rates, high lipid contents and tremendous potential for water conservation and CO2 biofixation. However, a bottleneck issue with algae biofuel manufacturing is the lack of cost-effective harvesting methods. This research focuses on the technologies for improved microalgae harvesting to enable commercially viable and environmentally friendly biodiesel production. The first objective of this study was to optimize flocculation of marine microalga Nannochloropsis oculata with metal salts, aluminum sulfate (A.S.) and ferric chloride (F.C.) via response surface methodology. It was found that there existed a positive stoichiometric relationship between the flocculant dose (FD) and the initial biomass concentration (IABC). Optimum flocculation conditions were predicted at IABC of 1.7 g/l, pH 8.3, and FD of 383.5 microM for A.S., and IABC of 2.2 g/l, pH 7.9, and FD of 438.1 microM for F.C., under which the predicted maximum harvested solid concentration of algae were 32.98 and 30.10 g/l by using A.S. and F.C., respectively. The second objective was to investigate the mechanism of microalgae flocculation with metal salts. The theory of Derjaguin, Landau, Verwey and Overbeek (DLVO) was applied to understand the flocculation mechanism of a freshwater alga Scenedesmus dimorphus and a marine alga Nannochloropsis oculata under various pH and aluminum sulphate ionic strengths. Effective flocculation was achieved as a result of charge neutralization and sweep flocculation. When low flocculant dosage (<0.1 mM) was applied, charge neutralization seemed to be predominating and the DLVO predicted flocculation trends were found quantitatively accurate in matching the experimental results. In the case of high flocculant dosage, the DLVO theory failed to explain the results since sweep flocculation was found to predominate at alum dose above 1 mM. Understanding of cell

Vibrational energy harvesting by exploring structural benefits and nonlinear characteristics

NASA Astrophysics Data System (ADS)

Wei, Chongfeng; Jing, Xingjian

2017-07-01

Traditional energy harvesters are often of low efficiency due to very limited energy harvesting bandwidth, which should also be enough close to the ambient excitation frequency. To overcome this difficulty, some attempts can be seen in the literature typically with the purposes of either increasing the energy harvesting bandwidth with a harvester array, or enhancing the energy harvesting bandwidth and peak with nonlinear coupling effect etc. This paper presents an alternative way which can achieve tuneable resonant frequency (from high frequency to ultralow frequency) and improved energy harvesting bandwidth and peak simultaneously by employing special structural benefits and advantageous displacement-dependent nonlinear damping property. The proposed energy harvesting system employs a lever systems combined with an X-shape supporting structure and demonstrates very adjustable stiffness and unique nonlinear damping characteristics which are very beneficial for energy harvesting. It is shown that the energy harvesting performance of the proposed system is directly determined by several easy-to-tune structural parameters and also by the relative displacement in a special nonlinear manner, which provides a great flexibility and/or a unique tool for tuning and improving energy harvesting efficiency via matching excitation frequencies and covering a broader frequency band. This study potentially provides a new insight into the design of energy harvesting systems by employing structural benefits and geometrical nonlinearities.

1971 Oregon timber harvest.

Treesearch

Brian R. Wall

1972-01-01

The 1971 Oregon timber harvest of 9.03 billion board feet was the highest since 1969 when 9.15 billion board feet was harvested. The 1971 total harvest was 13.1 percent above the 1970 figure. Western Oregon's harvest rose 11-5 percent, and eastern Oregon's harvest rose 18.6 percent.

Enhanced drinking water supply through harvested rainwater treatment

NASA Astrophysics Data System (ADS)

Naddeo, Vincenzo; Scannapieco, Davide; Belgiorno, Vincenzo

2013-08-01

Decentralized drinking water systems represent an important element in the process of achieving the Millennium Development Goals, as centralized systems are often inefficient or nonexistent in developing countries. In those countries, most water quality related problems are due to hygiene factors and pathogens. A potential solution might include decentralized systems, which might rely on thermal and/or UV disinfection methods as well as physical and chemical treatments to provide drinking water from rainwater. For application in developing countries, decentralized systems major constraints include low cost, ease of use, environmental sustainability, reduced maintenance and independence from energy sources. This work focuses on an innovative decentralized system that can be used to collect and treat rainwater for potable use (drinking and cooking purposes) of a single household, or a small community. The experimented treatment system combines in one compact unit a Filtration process with an adsorption step on GAC and a UV disinfection phase in an innovative design (FAD - Filtration Adsorption Disinfection). All tests have been carried out using a full scale FAD treatment unit. The efficiency of FAD technology has been discussed in terms of pH, turbidity, COD, TOC, DOC, Escherichia coli and Total coliforms. FAD technology is attractive since it provides a total barrier for pathogens and organic contaminants, and reduces turbidity, thus increasing the overall quality of the water. The FAD unit costs are low, especially if compared to other water treatment technologies and could become a viable option for developing countries.

Wood fuel potential from harvested areas in the eastern United States.

Treesearch

Eugene M. Carpenter

1980-01-01

Estimates amount of wood fiber that could be available for fuel from forest residues on harvested areas in the eastern United States. Includes a key to resource data published by the USDA Forest Service and factors for estimating amounts of cull, bark, tops, and limbs from inventory and product output tabulations.

The Impacts of Water Conservation Strategies on Water Use: Four Case Studies1

PubMed Central

Tsai, Yushiou; Cohen, Sara; Vogel, Richard M

2011-01-01

We assessed impacts on water use achieved by implementation of controlled experiments relating to four water conservation strategies in four towns within the Ipswich watershed in Massachusetts. The strategies included (1) installation of weather-sensitive irrigation controller switches (WSICS) in residences and municipal athletic fields; (2) installation of rainwater harvesting systems in residences; (3) two outreach programs: (a) free home indoor water use audits and water fixture retrofit kits and (b) rebates for low-water-demand toilets and washing machines; and (4) soil amendments to improve soil moisture retention at a municipal athletic field. The goals of this study are to summarize the effectiveness of the four water conservation strategies and to introduce nonparametric statistical methods for evaluating the effectiveness of these conservation strategies in reducing water use. It was found that (1) the municipal WSICS significantly reduced water use; (2) residences with high irrigation demand were more likely than low water users to experience a substantial demand decrease when equipped with the WSICS; (3) rainwater harvesting provided substantial rainwater use, but these volumes were small relative to total domestic water use and relative to the natural fluctuations in domestic water use; (4) both the audits/retrofit and rebate programs resulted in significant water savings; and (5) a modeling approach showed potential water savings from soil amendments in ball fields. PMID:22457572

Effects of harvesting forest biomass on water and climate regulation services: A synthesis of long-term ecosystem experiments in eastern North America

USGS Publications Warehouse

Caputo, Jesse; Beier, Colin D; Groffman, Peter M; Burns, Douglas A.; Beall, Frederick D; Hazlett, Paul W.; Yorks, Thad E

2016-01-01

Demand for woody biomass fuels is increasing amidst concerns about global energy security and climate change, but there may be negative implications of increased harvesting for forest ecosystem functions and their benefits to society (ecosystem services). Using new methods for assessing ecosystem services based on long-term experimental research, post-harvest changes in ten potential benefits were assessed for ten first-order northern hardwood forest watersheds at three long-term experimental research sites in northeastern North America. As expected, we observed near-term tradeoffs between biomass provision and greenhouse gas regulation, as well as tradeoffs between intensive harvest and the capacity of the forest to remediate nutrient pollution. In both cases, service provision began to recover along with the regeneration of forest vegetation; in the case of pollution remediation, the service recovered to pre-harvest levels within 10 years. By contrast to these two services, biomass harvesting had relatively nominal and transient impacts on other ecosystem services. Our results are sensitive to empirical definitions of societal demand, including methods for scaling societal demand to ecosystem units, which are often poorly resolved. Reducing uncertainty around these parameters can improve confidence in our results and increase their relevance for decision-making. Our synthesis of long-term experimental studies provides insights on the social-ecological resilience of managed forest ecosystems to multiple drivers of change.

The contribution of lakes to global inland fisheries harvest

USGS Publications Warehouse

Deines, Andrew M.; Bunnell, David B.; Rogers, Mark W.; Bennion, David; Woelmer, Whitney; Sayers, Michael J.; Grimm, Amanda G.; Shuchman, Robert A.; Raymer, Zachary B.; Brooks, Colin N.; Mychek-Londer, Justin G.; Taylor, William W.; Beard, Douglas

2017-01-01

Freshwater ecosystems provide numerous services for communities worldwide, including irrigation, hydropower, and municipal water; however, the services provided by inland fisheries – nourishment, employment, and recreational opportunities – are often comparatively undervalued. We provide an independent estimate of global lake harvest to improve biological and socioeconomic assessments of inland fisheries. On the basis of satellite-derived estimates of chlorophyll concentration from 80,012 globally distributed lakes, lake-specific fishing effort based on human population, and output from a Bayesian hierarchical model, we estimated that the global lake fishery harvest in the year 2011 was 8.4 million tons (mt). Our calculations excluded harvests from highly productive rivers, wetlands, and very small lakes; therefore, the true cumulative global fishery harvest from all freshwater sources likely exceeded 11 mt as reported by the Food and Agriculture Organization of the United Nations (FAO). This putative underestimate by the FAO could diminish the perceived importance of inland fisheries and perpetuate decisions that adversely affect these fisheries and millions of people.

From lab to full-scale ultrafiltration in microalgae harvesting

NASA Astrophysics Data System (ADS)

Wenten, I. G.; Steven, S.; Dwiputra, A.; Khoiruddin; Hakim, A. N.

2017-07-01

Ponding system is generally used for microalgae cultivation. However, selection of appropriate technology for the harvesting process is challenging due to the low cell density of cultivated microalgae from the ponding system and the large volume of water to be handled. One of the promising technologies for microalgae harvesting is ultrafiltration (UF). In this study, the performance of UF during harvesting of microalgae in a lab- and a full-scale test is investigated. The performances of both scales are compared and analyzed to provide an understanding of several aspects which affect the yield produced from lab and actual conditions. Furthermore, a unique self-standing non-modular UF is introduced in the full-scale test. The non-modular UF exhibits several advantages, such as simple piping and connection, single pump for filtration and backwashing, and smaller footprint. With those advantages, the non-modular UF could be a promising technology for microalgae harvesting in industrial-scale.

Harvesting

Treesearch

John R. Jones; Wayne D. Shepperd

1985-01-01

Harvesting is the removal of produce from the forest for utilization. It includes cutting, any further initial processing, such as topping and trimming, and extraction (Ford-Robertson 1971). Commercial intermediate cutting, such as commercial thinning, as well as regeneration cutting are included. Harvesting and the income that it produces sometimes is regarded as an...

Relationship of Water Potential to Growth of Leaves 1

PubMed Central

Boyer, John S.

1968-01-01

A thermocouple psychrometer that measures water potentials of intact leaves was used to study the water potentials at which leaves grow. Water potentials and water uptake during recovery from water deficits were measured simultaneously with leaves of sunflower (Helianthus annuus L.), tomato (Lycopersicon esculentum Mill.), papaya (Carica papaya L.), and Abutilon striatum Dickson. Recovery occurred in 2 phases. The first was associated with elimination of water deficits; the second with cell enlargement. The second phase was characterized by a steady rate of water uptake and a relatively constant leaf water potential. Enlargement was 70% irreversible and could be inhibited by puromycin and actinomycin D. During this time, leaves growing with their petioles in contact with pure water remained at a water potential of —1.5 to —2.5 bars regardless of the length of the experiment. It was not possible to obtain growing leaf tissue with a water potential of zero. It was concluded that leaves are not in equilibrium with the potential of the water which is absorbed during growth. The nonequilibrium is brought about by a resistance to water flow which requires a potential difference of 1.5 to 2.5 bars in order to supply water at the rate necessary for maximum growth. Leaf growth occurred in sunflower only when leaf water potentials were above —3.5 bars. Sunflower leaves therefore require a minimum turgor for enlargement, in this instance equivalent to a turgor of about 6.5 bars. The high water potentials required for growth favored rapid leaf growth at night and reduced growth during the day. PMID:16656882

The Effect of Plant Cultivar, Growth Media, Harvest Method and Post Harvest Treatment on the Microbiology of Edible Crops

NASA Technical Reports Server (NTRS)

Hummerick, Mary P.; Gates, Justin R.; Nguyen, Bao-Thang; Massa, Gioia D.; Wheeler, Raymond M.

2011-01-01

Systems for the growth of crops in closed environments are being developed and tested for potential use in space applications to provide a source of fresh food. Plant growth conditions, growth media composition and harvest methods can have an effect on the microbial population of the plant, and therefore should be considered along with the optimization of plant growth and harvest yields to ensure a safe and palatable food crop. This work examines the effect of plant cultivar, growth media, and harvest method on plant microbial populations. Twelve varieties of leafy greens and herbs were grown on a mixture of Fafard #2 and Arcillite in the pillow root containment system currently being considered for the VEGGIE plant growth unit developed by Orbitec. In addition, ,Sierra and Outredgeous lettuce varieties were grown in three different mixtures (Fafard #2, Ardllite, and Perlite/Vermiculite). The plants were analyzed for microbial density. Two harvest methods, "cut and come again" (CACA) and terminal harvest were also compared. In one set ofexpe'riments red leaf lettuce and mizuna were grown in pots in a Biomass Production System for education. Plants were harvested every two weeks by either method. Another set of experiments was performed using the rooting pillows to grow 5 varieties of leafy greens and cut harvesting at different intervals. Radishes were harvested and replanted at two-week intervals. Results indicate up to a 3 IOglO difference in microbial counts between some varieties of plants. Rooting medium resulted in an approximately 2 IOglO lower count in the lettuce grown in arscillite then those grown in the other mixtures. Harvest method and frequency had less impact on microbial counts only showing a significant increase in one variety of plant. Post harvest methods to decrease the bacterial counts on edible crops were investigated in these and other experiments. The effectiveness of PRO-SAN and UV-C radiation is compared.

A Survey of Timber Harvesting Simulation Models for Use in the South

Treesearch

Daniel V. Goulet; Donald L. Sirois; Ronald H. Iff

1979-01-01

Reviews literature about nine forest harvesting simulation models with potential for simulating southern operations. From the nine, five appearusefulenough to warrant further analysis.An annotated bibliography of associated forest harvesting simulation literature is appended.

Reviving the Ganges Water Machine: potential

NASA Astrophysics Data System (ADS)

Amarasinghe, Upali Ananda; Muthuwatta, Lal; Surinaidu, Lagudu; Anand, Sumit; Jain, Sharad Kumar

2016-03-01

The Ganges River basin faces severe water challenges related to a mismatch between supply and demand. Although the basin has abundant surface water and groundwater resources, the seasonal monsoon causes a mismatch between supply and demand as well as flooding. Water availability and flood potential is high during the 3-4 months (June-September) of the monsoon season. Yet, the highest demands occur during the 8-9 months (October-May) of the non-monsoon period. Addressing this mismatch, which is likely to increase with increasing demand, requires substantial additional storage for both flood reduction and improvements in water supply. Due to hydrogeological, environmental, and social constraints, expansion of surface storage in the Ganges River basin is problematic. A range of interventions that focus more on the use of subsurface storage (SSS), and on the acceleration of surface-subsurface water exchange, has long been known as the Ganges Water Machine (GWM). The approach of the GWM for providing such SSS is through additional pumping and depleting of the groundwater resources prior to the onset of the monsoon season and recharging the SSS through monsoon surface runoff. An important condition for creating such SSS is the degree of unmet water demand. The paper shows that the potential unmet water demand ranging from 59 to 124 Bm3 year-1 exists under two different irrigation water use scenarios: (i) to increase irrigation in the Rabi (November-March) and hot weather (April-May) seasons in India, and the Aman (July-November) and Boro (December-May) seasons in Bangladesh, to the entire irrigable area, and (ii) to provide irrigation to Rabi and the hot weather season in India and the Aman and Boro seasons in Bangladesh to the entire cropped area. However, the potential for realizing the unmet irrigation demand is high only in 7 sub-basins in the northern and eastern parts, is moderate to low in 11 sub-basins in the middle, and has little or no potential in 4 sub

Simulating adaptive wood harvest in a changing climate

NASA Astrophysics Data System (ADS)

Yousefpour, Rasoul; Nabel, Julia; Pongratz, Julia

2016-04-01

The world's forest experience substantial carbon exchange fluxes between land and atmosphere. Large carbon sinks occur in response to changes in environmental conditions (such as climate change and increased atmospheric CO2 concentrations), removing about one quarter of current anthropogenic CO2-emissions. Large sinks also occur due to regrowth of forest on areas of agricultural abandonment or forest management. Forest management, on the other hand, also leads to substantial amounts of carbon being eventually released to the atmosphere. Both sinks and sources attributable to forests are therefore dependent on the intensity of management. Forest management in turn depends on the availability of resources, which is influenced by environmental conditions and sustainability of management systems applied. Estimating future carbon fluxes therefore requires accounting for the interaction of environmental conditions, forest growth, and management. However, this interaction is not fully captured by current modeling approaches: Earth system models depict in detail interactions between climate, the carbon cycle, and vegetation growth, but use prescribed information on management. Resource needs and land management, however, are simulated by Integrated Assessment Models that typically only have coarse representations of the influence of environmental changes on vegetation growth and are typically based on the demand for wood driven by regional population growth and energy needs. Here we present a study that provides the link between environmental conditions, forest growth and management. We extend the land component JSBACH of the Max Planck Institute's Earth system model (MPI-ESM) to simulate potential wood harvest in response to altered growth conditions and thus as adaptive to changing climate and CO2 conditions. We apply the altered model to estimate potential wood harvest for future climates (representative concentration pathways, RCPs) for the management scenario of

Salmonella in lymph nodes of cull and fed cattle at harvest

USDA-ARS?s Scientific Manuscript database

Category: Pre-harvest pathogen reduction Objective: To evaluate the potential association between Salmonella enterica burden within bovine subiliac lymph nodes (LNs), animal type, season, and region of harvest. Methods: Bovine LNs (n = 4,764) were collected from 12 abattoirs, 8 that primarily h...

1972 Oregon timber harvest.

Treesearch

J.D. Jr. Lloyd

1973-01-01

The 1972 Oregon timber harvest of 9.6 billion board feet was 602 million board feet (6.7 percent) above the 1971 harvest. Western Oregon's harvest rose 8 percent and eastern Oregon's harvest rose 2 percent.

Energy Harvesting from Aerodynamic Instabilities: Current prospect and Future Trends

NASA Astrophysics Data System (ADS)

Bashir, M.; Rajendran, P.; Khan, S. A.

2018-01-01

This paper evaluates the layout and advancement of energy harvesting based on aerodynamic instabilities of an aircraft. Vibration and thermoelectric energy harvesters are substantiated as most suitable alternative low-power sources for aerospace applications. Furthermore, the facility associated with the aircraft applications in harvesting the mechanical vibrations and converting it to electric energy has fascinated the researchers. These devices are designed as an alternative to a battery-based solution especially for small aircrafts, wireless structural health monitoring for aircraft systems, and harvester plates employed in UAVs to enhance the endurance and operational flight missions. We will emphasize on various sources of energy harvesting that are designed to come from aerodynamic flow-induced vibrations, specific attention is then given at those technologies that may offer, today or in the near future, a potential benefit to reduce both the cost and emissions of the aviation industry. The advancements achieved in the energy harvesting based on aerodynamic instabilities show very good scope for many piezoelectric harvesters in the field of aerospace, specifically green aviation technology in the future.

The greenhouse gas intensity and potential biofuel production capacity of maize stover harvest in the US Midwest

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, Curtis D.; Zhang, Xuesong; Reddy, Ashwan D.

Agricultural residues are important sources of feedstock for a cellulosic biofuels industry that is being developed to reduce greenhouse gas emissions and improve energy independence. While the US Midwest has been recognized as key to providing maize stover for meeting near-term cellulosic biofuel production goals, there is uncertainty that such feedstocks can produce biofuels that meet federal cellulosic standards. Here, we conducted extensive site-level calibration of the Environmental Policy Integrated Climate (EPIC) terrestrial ecosystems model and applied the model at high spatial resolution across the US Midwest to improve estimates of the maximum production potential and greenhouse gas emissions expectedmore » from continuous maize residue-derived biofuels. A comparison of methodologies for calculating the soil carbon impacts of residue harvesting demonstrates the large impact of study duration, depth of soil considered, and inclusion of litter carbon in soil carbon change calculations on the estimated greenhouse gas intensity of maize stover-derived biofuels. Using the most representative methodology for assessing long-term residue harvesting impacts, we estimate that only 5.3 billion liters per year (bly) of ethanol, or 8.7% of the near-term US cellulosic biofuel demand, could be met under common no-till farming practices. However, appreciably more feedstock becomes available at modestly higher emissions levels, with potential for 89.0 bly of ethanol production meeting US advanced biofuel standards. Adjustments to management practices, such as adding cover crops to no-till management, will be required to produce sufficient quantities of residue meeting the greenhouse gas emission reduction standard for cellulosic biofuels. Considering the rapid increase in residue availability with modest relaxations in GHG reduction level, it is expected that management practices with modest benefits to soil carbon would allow considerable expansion of potential

Measuring Water Potential (Activity) from Free Water to Oven Dryness 1

PubMed Central

Wiebe, Herman H.

1981-01-01

Water activities (potentials) in plant materials were measured over the range from free water to oven dryness with a Spanner thermocouple psychrometer. In a two-step procedure, water was first condensed on the thermocouple junction for several minutes. The sample was then inserted under the wet thermocouple and the maximum psychrometric cooling was measured in about 10 seconds. Calibration was with saturated salt slurries of known water activities. Psychrometric cooling was a nearly linear function of the water activity and of the negative log of the water potential. The psychrometric cooling to water activity relationship agreed with wetbulb temperature depression to relative humidity relationships given in tables. Water activities of wheat grains and leaves decreased sharply in a curvilinear fashion as their water contents decreased. Some problems of the procedure are discussed. Images PMID:16662081

Leaf water potentials measured with a pressure chamber.

PubMed

Boyer, J S

1967-01-01

Leaf water potentials were estimated from the sum of the balancing pressure measured with a pressure chamber and the osmotic potential of the xylem sap in leafy shoots or leaves. When leaf water potentials in yew, rhododendron, and sunflower were compared with those measured with a thermocouple psychrometer known to indicate accurate values of leaf water potential, determinations were within +/- 2 bars of the psychrometer measurements with sunflower and yew. In rhododendron. water potentials measured with the pressure chamber plus xylem sap were 2.5 bars less negative to 4 bars more negative than psychrometer measurements.The discrepancies in the rhododendron measurements could be attributed, at least in part, to the filling of tissues other than xylem with xylem sap during measurements with the pressure chamber. It was concluded that, although stem characteristics may affect the measurements, pressure chamber determinations were sufficiently close to psychrometer measurements that the pressure chamber may be used for relative measurements of leaf water potentials, especially in sunflower and yew. For accurate determinations of leaf water potential, however, pressure chamber measurements must be calibrated with a thermocouple psychrometer.

Planetary opportunities in crop water management: Potential to outweigh cropland expansion

NASA Astrophysics Data System (ADS)

Jägermeyr, Jonas; Gerten, Dieter; Lucht, Wolfgang; Heinke, Jens

2014-05-01

Global available land and water resources probably cannot feed projected future human populations under current productivity levels. Moreover, the planetary boundaries of both land use change and water consumption are being approached rapidly, and at the same time competition between food production, bioenergy plantations and biodiversity conservation is increasing. Global cropland is expected to expand to meet future demands, while considerable yield gaps remain in many world regions. Yield increases in Sub-Saharan Africa, for example, are currently mainly based on expansion of arable land into currently non-agricultural areas - while small-scale irrigation and water conservancy methods are considered very promising to boost yields there. In the here presented modeling study we investigate, at global scale, to what degree different on-farm options to better manage green and blue water might contribute to a global crop yield increase under conditions of current climate and projected future climate change. We consider methods aiming for a maximization of crops' water use efficiency and an optimal use of available on-farm water (precipitation): reducing unproductive soil evaporation (vapor shift, VS), collecting surface runoff after rain events to mitigate subsequent dry-spells (rain-water harvesting, RWH), increasing irrigation efficiency, and expanding irrigated area into rain-fed cropland (based on water savings from higher efficiencies). Global yield simulations based on hypothetical scenarios of these management opportunities are performed with the LPJmL ecohydrological modeling framework driven by reanalysis data and GCM ensemble simulations. We consider a range of about 20 climate change projections to cover respective uncertainties, and we analyze the effects of increasing CO2 concentration on the crops and their water demand. Crops are represented in a process-based and dynamic way by 12 crop functional types, each for rain-fed and irrigated areas, with

1975 Oregon timber harvest.

Treesearch

J.D. Jr. Lloyd

1976-01-01

The 1975 Oregon timber harvest declined to its lowest level since 1961 with a harvest of 7.37 billion board feet, 991 million board feet (11.9 percent) below the 1974 harvest. The harvest was down in both western Oregon (823 million board feet, 13.2 percent) and eastern Oregon (168 million board feet, 7.7 percent). For the first time since 1961, the harvest on private...

Construction and Evaluation of Rainwater Harvesting System for Domestic Use in a Remote and Rural Area of Khulna, Bangladesh.

PubMed

Biswas, Biplob Kumar; Mandal, Bablu Hira

2014-01-01

Scarcity of pure drinking water during the dry season (November-March) is a major problem in Bangladesh, which needs to be addressed. This crisis has been further aggravated due to surging populations. Rainwater can provide some of the cleanest naturally occurring water and can hold a great potential in dealing with the current challenge of acute arsenic poisoning as well as physical water scarcity in many parts of Bangladesh. In this connection, rainwater harvesting (RWH) system has been constructed in a very remote and rural village in Khulna, Bangladesh, for a 4-membered household. It consists of a concrete catchment of 40 m(2) area, a supporting and collection system made of PVC pipes, and two locally available plastic storage tanks having capacity of 2000 L each. The study also investigates the quality aspects of the stored rainwater, which include measurement of pH, alkalinity, hardness, total dissolved solids (TDS), iron, chloride, nitrate, and turbidity, using standard methods. The results showed that not only the quality of harvested rainwater is good but also the amount of water is enough for a 4-membered household to meet its domestic use throughout the year.

Post-harvest physiology

USDA-ARS?s Scientific Manuscript database

Weather and management constraints, as well as the intended use of the harvested forage, all influence the forage harvest system selected by the producer. Generally, maximum retention of dry matter from harvested forage crops is achieved at moistures intermediate between the standing fresh crop and ...

Effect of climate change on sowing and harvest dates of spring barley and maize in Poland

NASA Astrophysics Data System (ADS)

Marcinkowski, Paweł; Piniewski, Mikołaj

2018-04-01

Climate change and projected temperature increase is recognised to have significant impact on agricultural production and crop phenology. This study evaluated the climate change impact on sowing and harvest dates of spring barley and maize in the boundaries of two largest catchments in Poland - the Vistula and the Odra. For this purpose, an agro-hydrological Soil and Water Assessment Tool has been used, driven by climate forcing data provided within the Coordinated Downscaling Experiment - European Domain experiment projected to the year 2100 under two representative concentration pathways: 4.5 and 8.5. The projected warmer climate significantly affected the potential scheduling of agricultural practices, accelerating the occurrence of sowing and harvest dates. The rate of acceleration was dependent on the time horizon and representative concentration pathways scenario. In general, the rate of sowing/harvest advance was accelerating in time and, also from representative concentration pathways 4.5 to 8.5, reaching 23 days for spring barley and 30 days for maize (ensemble mean for the far future under representative concentration pathways 8.5).

Novel composite piezoelectric material for energy harvesting applications

NASA Astrophysics Data System (ADS)

Janusas, Giedrius; Guobiene, Asta; Palevicius, Arvydas; Prosycevas, Igoris; Ponelyte, Sigita; Baltrusaitis, Valentinas; Sakalys, Rokas

2015-04-01

Past few decades were concentrated on researches related to effective energy harvesting applied in modern technologies, MEMS or MOEMS systems. There are many methods for harvesting energy as, for example, usage of electromagnetic devices, but most dramatic changes were noticed in the usage of piezoelectric materials in small scale devices. Major limitation faced was too small generated power by piezoelectric materials or high resonant frequencies of such smallscale harvesters. In this research, novel composite piezoelectric material was created by mixing PZT powder with 20% solution of polyvinyl butyral in benzyl alcohol. Obtained paste was screen printed on copper foil using 325 mesh stainless steel screen and dried for 30 min at 100 °C. Polyvinyl butyral ensures good adhesion and flexibility of a new material at the conditions that requires strong binding. Five types of a composite piezoelectric material with different concentrations of PZT (40%, 50%, 60%, 70% and 80 %) were produced. As the results showed, these harvesters were able to transform mechanical strain energy into electric potential and, v.v. In experimental setup, electromagnetic shaker was used to excite energy harvester that is fixed in the custom-built clamp, while generated electric potential were registered with USB oscilloscope PICO 3424. The designed devices generate up to 80 μV at 50 Hz excitation. This property can be applied to power microsystem devices or to use them in portable electronics and wireless sensors. However, the main advantage of the created composite piezoelectric material is possibility to apply it on any uniform or nonuniform vibrating surface and to transform low frequency vibrations into electricity.

Life cycle and hydrologic modeling of rainwater harvesting in urban neighborhoods: Implications of urban form and water demand patterns in the US and Spain.

PubMed

Petit-Boix, Anna; Devkota, Jay; Phillips, Robert; Vargas-Parra, María Violeta; Josa, Alejandro; Gabarrell, Xavier; Rieradevall, Joan; Apul, Defne

2018-04-15

Water management plays a major role in any city, but applying alternative strategies might be more or less feasible depending on the urban form and water demand. This paper aims to compare the environmental performance of implementing rainwater harvesting (RWH) systems in American and European cities. To do so, two neighborhoods with a water-stressed Mediterranean climate were selected in contrasting cities, i.e., Calafell (Catalonia, Spain) and Ukiah (California, US). Calafell is a high-density, tourist city, whereas Ukiah is a typical sprawled area. We studied the life cycle impacts of RWH in urban contexts by using runoff modeling before (i.e. business as usual) and after the implementation of this system. In general, cisterns were able to supply >75% of the rainwater demand for laundry and toilet flushing. The exception were multi-story buildings with roofs smaller than 200m 2 , where the catchment area was insufficient to meet demand. The implementation of RWH was environmentally beneficial with respect to the business-as-usual scenario, especially because of reduced runoff treatment needs. Along with soil features, roof area and water demand were major parameters that affected this reduction. RWH systems are more attractive in Calafell, which had 60% lower impacts than in Ukiah. Therefore, high-density areas can potentially benefit more from RWH than sprawled cities. Copyright © 2017 Elsevier B.V. All rights reserved.

Potential of combined Water Sensitive Urban Design systems for salinity treatment in urban environments.

PubMed

Kazemi, Fatemeh; Golzarian, Mahmood Reza; Myers, Baden

2018-03-01

Water sensitive urban design and similar concepts often recommend a 'treatment train' is employed to improve stormwater quality. In this study, the capability of a combined permeable pavement and bioretention basin was examined with a view to developing a permeable pavement reservoir that can supplement the irrigation needs of a bioretention system in semi-arid climates. Salinity was a key study parameter due to published data on salinity in permeable pavement storage, and the potential to harvest water contaminated with de-icing salts. To conduct experiments, roofwater was collected from a roof in Adelaide, South Australia. Water was amended with NaCl to produce a control runoff (no added salt), a medium (500 mg/l) and a high (1500 mg/l) salinity runoff. Water was then run through the pavement into the storage reservoir and used to irrigate the bioretention system. Samples were collected from the roof, the pavement reservoir and the bioretention system outflow to determine whether significant water quality impacts occurred. Results show that while salinity levels increased significantly as water passed through the pavement and through the bioretention system, the increase was beneficial for irrigation purposes as it was from Ca and Mg ions thus reducing the sodium absorption ratio to levels considered 'good' for irrigation in accordance with several guidelines. Permeable paving increased pH of water and this effect was prominent when the initial salt concentration increased. The study shows that permeable pavements with underlying storage can be used to provide supplementary irrigation for bioretention systems, but high initial salt concentrations may present constraints on beneficial use of stormwater. Copyright © 2017. Published by Elsevier Ltd.

Energy harvesting influences electrochemical performance of microbial fuel cells

NASA Astrophysics Data System (ADS)

Lobo, Fernanda Leite; Wang, Xin; Ren, Zhiyong Jason

2017-07-01

Microbial fuel cells (MFCs) can be effective power sources for remote sensing, wastewater treatment and environmental remediation, but their performance needs significant improvement. This study systematically analyzes how active harvesting using electrical circuits increased MFC system outputs as compared to passive resistors not only in the traditional maximal power point (MPP) but also in other desired operating points such as the maximum current point (MCP) and the maximum voltage point (MVP). Results show that active harvesting in MPP increased power output by 81-375% and active harvesting in MCP increased Coulombic efficiency by 207-805% compared with resisters operated at the same points. The cyclic voltammograms revealed redox potential shifts and supported the performance data. The findings demonstrate that active harvesting is a very effective approach to improve MFC performance across different operating points.

Hybrid nanogenerator for concurrently harvesting biomechanical and biochemical energy.

PubMed

Hansen, Benjamin J; Liu, Ying; Yang, Rusen; Wang, Zhong Lin

2010-07-27

Harvesting energy from multiple sources available in our personal and daily environments is highly desirable, not only for powering personal electronics, but also for future implantable sensor-transmitter devices for biomedical and healthcare applications. Here we present a hybrid energy scavenging device for potential in vivo applications. The hybrid device consists of a piezoelectric poly(vinylidene fluoride) nanofiber nanogenerator for harvesting mechanical energy, such as from breathing or from the beat of a heart, and a flexible enzymatic biofuel cell for harvesting the biochemical (glucose/O2) energy in biofluid, which are two types of energy available in vivo. The two energy harvesting approaches can work simultaneously or individually, thereby boosting output and lifetime. Using the hybrid device, we demonstrate a "self-powered" nanosystem by powering a ZnO nanowire UV light sensor.

Momentum harvesting techniques for solar system travel

NASA Technical Reports Server (NTRS)

Willoughby, Alan J.

1991-01-01

Astronomers are lately estimating there are 400,000 earth visiting asteroids larger than 100 meters in diameter. These asteroids are uniquely accessible sources of building materials, propellants, oxygen, water, and minerals. They also constitute a huge momentum reserve, potentially usable for travel throughout the solar system. To use this momentum, these stealthy objects must be tracked and the ability to extract the desired momentum obtained. Momentum harvesting by momentum transfer from asteroid to spacecraft, and by using the momentum of the extraterrestrial material to help deliver itself to its destination is discussed. The purpose is neither to quantify nor justify the momentum exchange processes, but to stimulate collective imaginations with some intriguing possibilities which emerge when momentum as well as material is considered. A net and tether concept is the suggested means of asteroid capture, the basic momentum exchange process. The energy damping characteristics of the tether determines the velocity mismatch that can be tolerated, and hence the amount of momentum that can be harvested per capture. As the tether plays out of its reel, drag on the tether steadily accelerates the spacecraft and dilutes, in time, the would-be collision. A variety of concepts for riding and using asteroids after capture are introduced. The hitchhiker uses momentum transfer only. The beachcomber, the caveman, the swinger, the prospector, and the rock wrecker also take advantage of raw asteroid materials. The chemist and the hijacker go further, they process the asteroid into propellants. Or, an asteroid railway system could be constructed with each hijacked asteroid becoming a scheduled train. Travelers could board this space railway system assured that water, oxygen propellants, and shielding await them. Austere space travel could give way to comforts, with a speed and economy impossible without nature's gift of earth visiting asteroids.

Harvesting electrostatic energy using super-hydrophobic surfaces

NASA Astrophysics Data System (ADS)

Pociecha, Dominik; Zylka, Pawel

2016-11-01

Almost all environments are now being extensively populated by miniaturized, nano-powered electronic sensor devices communicated together through wireless sensor networks building Internet of Things (IoT). Various energy harvesting techniques are being more and more frequently proposed for battery-less powering of such remote, unattended, implantable or wearable sensors or other low-power electronic gadgets. Energy harvesting relays on extracting energy from the ambient sources readily accessible at the sensor location and converting it into electrical power. The paper exploits possibility of generating electric energy safely accessible for nano-power electronics using tribo-electric and electrostatic induction phenomena displayed at super-hydrophobic surfaces impinged by water droplets. Mechanism of such interaction is discussed and illustrated by experimental results.

Effects of Proof Mass Geometry on Piezoelectric Vibration Energy Harvesters.

PubMed

Alameh, Abdul Hafiz; Gratuze, Mathieu; Elsayed, Mohannad Y; Nabki, Frederic

2018-05-16

Piezoelectric energy harvesters have proven to have the potential to be a power source in a wide range of applications. As the harvester dimensions scale down, the resonance frequencies of these devices increase drastically. Proof masses are essential in micro-scale devices in order to decrease the resonance frequency and increase the strain along the beam to increase the output power. In this work, the effects of proof mass geometry on piezoelectric energy harvesters are studied. Different geometrical dimension ratios have significant impact on the resonance frequency, e.g., beam to mass lengths, and beam to mass widths. A piezoelectric energy harvester has been fabricated and tested operating at a frequency of about 4 kHz within the audible range. The responses of various prototypes were studied, and an optimized T-shaped piezoelectric vibration energy harvester design is presented for improved performance.

Metamaterials-based enhanced energy harvesting: A review

NASA Astrophysics Data System (ADS)

Chen, Zhongsheng; Guo, Bin; Yang, Yongmin; Cheng, Congcong

2014-04-01

Advances in low power design open the possibility to harvest ambient energies to power directly the electronics or recharge a secondary battery. The key parameter of an energy harvesting (EH) device is its efficiency, which strongly depends on the conversion medium. To address this issue, metamaterials, artificial materials and structures with exotic properties, have been introduced for EH in recent years. They possess unique properties not easily achieved using naturally occurring materials, such as negative stiffness, mass, Poisson's ratio, and refractive index. The goal of this paper is to review the fundamentals, recent progresses and future directions in the field of metamaterials-based enhanced energy harvesting. An introduction on EH followed by the classification of potential metamaterials for EH is presented. A number of theoretical and experimental studies on metamaterials-based EH are outlined, including phononic crystals, acoustic metamaterials, and electromagnetic metamaterials. Finally, we give an outlook on future directions of metamaterials-based energy harvesting research including but not limited to active metamaterials-based EH, metamaterials-based thermal EH, and metamaterials-based multifunctional EH capabilities.

Forest soil carbon is threatened by intensive biomass harvesting.

PubMed

Achat, David L; Fortin, Mathieu; Landmann, Guy; Ringeval, Bruno; Augusto, Laurent

2015-11-04

Forests play a key role in the carbon cycle as they store huge quantities of organic carbon, most of which is stored in soils, with a smaller part being held in vegetation. While the carbon storage capacity of forests is influenced by forestry, the long-term impacts of forest managers' decisions on soil organic carbon (SOC) remain unclear. Using a meta-analysis approach, we showed that conventional biomass harvests preserved the SOC of forests, unlike intensive harvests where logging residues were harvested to produce fuelwood. Conventional harvests caused a decrease in carbon storage in the forest floor, but when the whole soil profile was taken into account, we found that this loss in the forest floor was compensated by an accumulation of SOC in deeper soil layers. Conversely, we found that intensive harvests led to SOC losses in all layers of forest soils. We assessed the potential impact of intensive harvests on the carbon budget, focusing on managed European forests. Estimated carbon losses from forest soils suggested that intensive biomass harvests could constitute an important source of carbon transfer from forests to the atmosphere (142-497 Tg-C), partly neutralizing the role of a carbon sink played by forest soils.

Broadband pendulum energy harvester

NASA Astrophysics Data System (ADS)

Liang, Changwei; Wu, You; Zuo, Lei

2016-09-01

A novel electromagnetic pendulum energy harvester with mechanical motion rectifier (MMR) is proposed and investigated in this paper. MMR is a mechanism which rectifies the bidirectional swing motion of the pendulum into unidirectional rotation of the generator by using two one-way clutches in the gear system. In this paper, two prototypes of pendulum energy harvester with MMR and without MMR are designed and fabricated. The dynamic model of the proposed MMR pendulum energy harvester is established by considering the engagement and disengagement of the one way clutches. The simulation results show that the proposed MMR pendulum energy harvester has a larger output power at high frequencies comparing with non-MMR pendulum energy harvester which benefits from the disengagement of one-way clutch during pendulum vibration. Moreover, the proposed MMR pendulum energy harvester is broadband compare with non-MMR pendulum energy harvester, especially when the equivalent inertia is large. An experiment is also conducted to compare the energy harvesting performance of these two prototypes. A flywheel is attached at the end of the generator to make the disengagement more significant. The experiment results also verify that MMR pendulum energy harvester is broadband and has a larger output power at high frequency over the non-MMR pendulum energy harvester.

Primary events regulating stem growth at low water potentials.

PubMed

Nonami, H; Boyer, J S

1990-08-01

Cell enlargement is inhibited by inadequate water. As a first step toward understanding the mechanism, all the physical parameters affecting enlargement were monitored to identify those that changed first, particularly in coincidence with the inhibition. The osmotic potential, turgor, yield threshold turgor, growth-induced water potential, wall extensibility, and conductance to water were measured in the elongating region, and the water potential was measured in the xylem of stems of dark-grown soybean (Glycine max [L.] Merr.) seedlings. A stepdown in water potential was achieved around the roots by transplanting the seedlings to vermiculite of low water content, and each of the parameters was measured simultaneously in the same plants while intact or within a few minutes of being intact using a newly developed guillotine psychrometer. The gradient of decreasing water potential from the xylem to the enlarging cells (growth-induced water potential) was the first of the parameters to decrease to a growth-limiting level. The kinetics were the same as for the inhibition of growth. The decreased gradient was caused mostly by a decreased water potential of the xylem. This was followed after 5 to 10 hours by a similar decrease in cell wall extensibility and tissue conductance for water. Later, the growth-induced water potential recovered as a result of osmotic adjustment and a rise in the water potential of the xylem. Still later, moderate growth resumed at a rate apparently determined by the low wall extensibility and tissue conductance for water. The turgor did not change significantly during the experiment. These results indicate that the primary event during the growth inhibition was the change in the growth-induced water potential. Because the growth limitation subsequently shifted to the low wall extensibility and tissue conductance for water, the initial change in potential may have set in motion subsequent metabolic changes that altered the characteristics of the

Leaf Water Potentials Measured with a Pressure Chamber

PubMed Central

Boyer, J. S.

1967-01-01

Leaf water potentials were estimated from the sum of the balancing pressure measured with a pressure chamber and the osmotic potential of the xylem sap in leafy shoots or leaves. When leaf water potentials in yew, rhododendron, and sunflower were compared with those measured with a thermocouple psychrometer known to indicate accurate values of leaf water potential, determinations were within ± 2 bars of the psychrometer measurements with sunflower and yew. In rhododendron. water potentials measured with the pressure chamber plus xylem sap were 2.5 bars less negative to 4 bars more negative than psychrometer measurements. The discrepancies in the rhododendron measurements could be attributed, at least in part, to the filling of tissues other than xylem with xylem sap during measurements with the pressure chamber. It was concluded that, although stem characteristics may affect the measurements, pressure chamber determinations were sufficiently close to psychrometer measurements that the pressure chamber may be used for relative measurements of leaf water potentials, especially in sunflower and yew. For accurate determinations of leaf water potential, however, pressure chamber measurements must be calibrated with a thermocouple psychrometer. PMID:16656476

A Five-Year Assessment of Corn Stover Harvest in Central Iowa, USA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Douglas L. Karlen; Stuart J. Birell; J. Richard Hess

differences, presumably because soil-test P was again in the low range. A soil quality analysis using the Soil Management Assessment Framework (SMAF) with six indicators showed that soils at the continuous corn and rotated sites were functioning at an average of 93 and 83% of their inherent potential, respectively. With good crop management practices, including routine soil-testing, adequate fertilization, maintenance of soil organic matter, sustained soil structure, and prevention of wind, water or tillage erosion, a portion of the corn stover being produced in central Iowa, USA can be harvested in a sustainable manner.« less

77 FR 17353 - Migratory Bird Subsistence Harvest in Alaska; Harvest Regulations for Migratory Birds in Alaska...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-26

... reduce the potential for shooting mortality or injury of closed species. These conservation measures..., meetings, radio shows, signs, school visits, and one-on-one contacts. We also recognize that no listed..., and in-season verification of the harvest. Our primary strategy to reduce the threat of shooting...

Does tree harvesting in riparian areas increase stream sedimentation and turbidity - world-wide experience relative to Australia.

NASA Astrophysics Data System (ADS)

Neary, D.; Smethurst, P.; Petrone, K.

2009-04-01

A typical improved-pasture property in the high-rainfall zone of Australia contains 0.5-2.0 km of waterways per 100 ha. Nationwide, some 25-30 million ha of improved pasture contains about 100,000 km of streams, of which about 75% are currently un-buffered and contributing to soil and water degradation. Farmers and natural resource managers are considering ways to enhance environmental outcomes at farm and catchment scales using stream-side buffers of trees and other perennial vegetation. Benefits of buffers include improved water quality, biodiversity, carbon sequestration and aesthetics. Lack of sound information and funding for establishing and managing buffer zones is hindering wide-scale adoption of this practice. Stream-side areas of farms are generally highly productive (wet and nutrient-rich) and contain a high biodiversity, but they are also high-risk zones for soil and water values and stock safety. Development of options based on a balance between environmental and economic outcomes would potentially promote wider adoption. Australian codes of forest practice currently discourage or prevent harvesting of trees in streamside buffers. These codes were developed exclusively for large-scale native forests and industrial-scale plantations, and were applicable to farm forestry as now required. In countries including USA and Germany trees in stream-side buffers are harvested using Best Management Practices. Trees may grow at a faster rate in riparian zones and provide a commercial return, but the impacts of tree establishment and harvesting on water yield and quality must be evaluated. However, there have been few designed experiments investigating this problem. Australia has recently initiated studies to explore the use of high-value timber species and associated vegetation in riparian zones to improve water quality, particularly suspended sediment. Preliminary information from the Yan Yan Gurt Catchment in Victoria indicate that forested riparian strips can

Development of Techniques to Investigate Sonoluminescence as a Source of Energy Harvesting

NASA Technical Reports Server (NTRS)

Wrbanek, John D.; Fralick, Gustave C.; Wrbanek, Susan Y.

2007-01-01

Instrumentation techniques are being developed at NASA Glenn Research Center to measure optical, radiation, and thermal properties of the phenomena of sonoluminescence, the light generated using acoustic cavitation. Initial efforts have been directed to the generation of the effect and the imaging of the glow in water and solvents. Several images have been produced of the effect showing the location within containers, without the additions of light enhancers to the liquid. Evidence of high energy generation in the modification of thin films from sonoluminescence in heavy water was seen that was not seen in light water. Bright, localized sonoluminescence was generated using glycerin for possible applications to energy harvesting. Issues to be resolved for an energy harvesting concept will be addressed.

Harvested rainwater quality before and after treatment in six full-scale residential systems

EPA Science Inventory

Rainwater harvesting (RWH) is an alternative method of providing water for indoor domestic use, but the water quality after treatment and distribution at individual residences is not well documented. In this study, water quality parameters were measured at the cistern and indoor ...

Effect of mating stage on water balance, cuticular hydrocarbons and metabolism in the desert harvester ant, Pogonomyrmex barbatus.

PubMed

Johnson, Robert A; Gibbs, Allen G

2004-10-01

Water-loss rates increase after mating in queens of the harvester ant Pogonomyrmex barbatus (Formicidae: Myrmicinae), then increase again after the mated queens excavate an incipient nest. We determined the mechanistic basis for these increased water-loss rates by examining cuticular permeability, respiratory water loss, metabolic rates, and cuticular hydrocarbons for queens at three stages in the mating sequence: unmated alate queens, newly mated dealate queens, and mated queens excavated from their incipient nest. Both total water loss and cuticular transpiration increased significantly following mating, with cuticular transpiration accounting for 97% of the increased water loss. In contrast, metabolic rate and respiratory water loss were unaffected by mating stage. The total quantity of cuticular hydrocarbons did not vary by mating stage. However, relative amounts of four of the most abundant cuticular hydrocarbons did vary by mating stage, as did quantities of n-alkanes and methylalkanes. The general pattern was that percent composition of n-alkanes decreased through the mating sequence, while percent composition of methylalkanes increased over the same sequence. We discuss three mechanisms that might cause these post-mating increases in cuticular permeability. Our data support the hypothesis that part of this increase results from soil particles abrading the cuticle during the process of nest excavation.

Fabrication and characterization of non-resonant magneto-mechanical low-frequency vibration energy harvester

NASA Astrophysics Data System (ADS)

Nammari, Abdullah; Caskey, Logan; Negrete, Johnny; Bardaweel, Hamzeh

2018-03-01

This article presents a non-resonant magneto-mechanical vibration energy harvester. When externally excited, the energy harvester converts vibrations into electric charge using a guided levitated magnet oscillating inside a multi-turn coil that is fixed around the exterior of the energy harvester. The levitated magnet is guided using four oblique mechanical springs. A prototype of the energy harvester is fabricated using additive manufacturing. Both experiment and model are used to characterize the static and dynamic behavior of the energy harvester. Measured restoring forces show that the fabricated energy harvester retains a mono-stable potential energy well with desired stiffness nonlinearities. Results show that magnetic spring results in hardening effect which increases the resonant frequency of the energy harvester. Additionally, oblique mechanical springs introduce geometric, negative, nonlinear stiffness which improves the harvester's response towards lower frequency spectrum. The unique design can produce a tunable energy harvester with multi-well potential energy characteristics. A finite element model is developed to estimate the average radial flux density experienced by the multi-turn coil. Also, a lumped parameter model of the energy harvester is developed and validated against measured data. Both upward and downward frequency sweeps are performed to determine the frequency response of the harvester. Results show that at higher excitation levels hardening effects become more apparent, and the system dynamic response turns into non-resonant. Frequency response curves exhibit frequency jump phenomena as a result of coexistence of multiple energy states at the frequency branch. The fabricated energy harvester is hand-held and measures approximately 100.5 [cm3] total volume. For a base excitation of 1.0 g [m/s2], the prototype generates a peak voltage and normalized power density of approximately 3.5 [V] and 0.133 [mW/cm3 g2], respectively, at 15.5 [Hz].

Probabilistic Impact Assessment of Domestic Rainwater Harvesting in Urban Slums: West Africa Case Study

NASA Astrophysics Data System (ADS)

Cowden, J. R.; Watkins, D. W.; Mihelcic, J. R.; Fry, L. M.

2007-12-01

Urban populations now exceed rural populations worldwide, creating unique challenges in providing basic services, especially in developing countries where informal or illegal settlements grow in peri-urban areas. West Africa is an acute example of the problems created by rapid urban growth, with high levels of urban poverty and low water and sanitation access rates. Although considerable effort has been made in providing improved water access and urban services to slum communities, research indicates that clean water access rates are not keeping up with urbanization rates in several areas of the world and that rapidly growing slum communities are beginning to overwhelm many prior water improvements projects. In the face of these challenges, domestic rainwater harvesting is proposed as a technologically appropriate and economically viable option for enhancing water supplies to urban slum households. However, assessing the reliability, potential health impacts, and overall cost-effectiveness of these systems on a regional level is difficult for several reasons. First, long daily rainfall records are not readily available in much of the developing world, including many regions of sub-Saharan Africa. Second, significant uncertainties exist in the relevant cost, water use, and health data. Third, to estimate the potential future impacts at the regional scale, various global change scenarios should be investigated. Finally, in addition to these technical challenges, there is also a need to develop relatively simple and transparent assessment methods for informing policy makers. A procedure is presented for assessment of domestic rainwater harvesting systems using a combination of scenario, sensitivity, and trade-off analyses. Using data from West Africa, simple stochastic weather models are developed to generate rainfall sequences for the region, which are then used to estimate the reliability of providing a range of per capita water supplies. Next, a procedure is

Insights from Placing Photosynthetic Light Harvesting into Context.

PubMed

Demmig-Adams, Barbara; Stewart, Jared J; Burch, Tyson A; Adams, William W

2014-08-21

Solar-energy conversion through natural photosynthesis forms the base of virtually all food chains on Earth and provides fiber, materials, and fuels, as well as inspiration for the design of biomimetic energy-conversion systems. We summarize well-known as well as recently discovered feedback loops between natural light-harvesting systems and whole-organism function in natural settings. We propose that the low effective quantum yield of natural light-harvesting systems in high light is caused by downstream limitations rather than unavoidable intrinsic vulnerabilities. We evaluate potential avenues, and their costs and benefits, for increasing the maximal rate and photon yield of photosynthesis in high light in plants and photosynthetic microbes. By summarizing mechanisms observable only in complex systems (whole plants, algae, or, in some cases, intact leaves), we aim to stimulate future research efforts on reciprocal feedback loops between light harvesting and downstream processes in whole organisms and to provide additional arguments for the significance of research on photosynthetic light harvesting.

Design optimization of PVDF-based piezoelectric energy harvesters.

PubMed

Song, Jundong; Zhao, Guanxing; Li, Bo; Wang, Jin

2017-09-01

Energy harvesting is a promising technology that powers the electronic devices via scavenging the ambient energy. Piezoelectric energy harvesters have attracted considerable interest for their high conversion efficiency and easy fabrication in minimized sensors and transducers. To improve the output capability of energy harvesters, properties of piezoelectric materials is an influential factor, but the potential of the material is less likely to be fully exploited without an optimized configuration. In this paper, an optimization strategy for PVDF-based cantilever-type energy harvesters is proposed to achieve the highest output power density with the given frequency and acceleration of the vibration source. It is shown that the maximum power output density only depends on the maximum allowable stress of the beam and the working frequency of the device, and these two factors can be obtained by adjusting the geometry of piezoelectric layers. The strategy is validated by coupled finite-element-circuit simulation and a practical device. The fabricated device within a volume of 13.1 mm 3 shows an output power of 112.8 μW which is comparable to that of the best-performing piezoceramic-based energy harvesters within the similar volume reported so far.

The summer flow and water yield response to timber harvest

Treesearch

Elizabeth T. Keppeler

1998-01-01

Continuous measurement of streamflow at the Caspar Creek watersheds has led to several analyses of the effects of two harvest methods (selection and clearcut) on summer flows and annual yield. Although all Caspar Creek analyses have indicated an increase in runoff after timber removal, the magnitude and duration of the response depend on the nature and extent of the...

Effects of Proof Mass Geometry on Piezoelectric Vibration Energy Harvesters

PubMed Central

Gratuze, Mathieu; Elsayed, Mohannad Y.

2018-01-01

Piezoelectric energy harvesters have proven to have the potential to be a power source in a wide range of applications. As the harvester dimensions scale down, the resonance frequencies of these devices increase drastically. Proof masses are essential in micro-scale devices in order to decrease the resonance frequency and increase the strain along the beam to increase the output power. In this work, the effects of proof mass geometry on piezoelectric energy harvesters are studied. Different geometrical dimension ratios have significant impact on the resonance frequency, e.g., beam to mass lengths, and beam to mass widths. A piezoelectric energy harvester has been fabricated and tested operating at a frequency of about 4 kHz within the audible range. The responses of various prototypes were studied, and an optimized T-shaped piezoelectric vibration energy harvester design is presented for improved performance. PMID:29772706

Timber-harvest clearcutting and nutrients in the Northeastern United States

Treesearch

K. G. Reinhart

1973-01-01

The effect of ecosystem disturbance on nutrients in the system has been receiving widespread attention. An appraisal of research results in the Northeast indicates that timber-harvest clearcutting has not increased nutrient levels sufficiently to reduce water quality below drinking water standards. Losses of nutrients from clearcuttings in New Hampshire over a 2-year...

Direct Demonstration of a Growth-Induced Water Potential Gradient.

PubMed

Nonami, H.; Boyer, J. S.

1993-05-01

When transpiration is negligible, water potentials in growing tissues are less than those in mature tissues and have been predicted to form gradients that move water into the enlarging cells. To determine directly whether the gradients exist, we measured water potentials along the radius of stems of intact soybean (Glycine max [L.] Merr.) seedlings growing in vermiculite in a water-saturated atmosphere. The measurements were made in individual cells by first determining the turgor with a miniature pressure probe, then determining the osmotic potential of solution from the same cell, and finally summing the two potentials. The osmotic potentials were corrected for sample mixing in the probe. The measurements were checked with a thermocouple psychrometer that gave average tissue water potentials. In the elongating region, the water potential was highest near the xylem and lowest near the epidermis and in the center of the pith. In the basal, more mature region of the same stems, water potentials were near zero next to the xylem and throughout the tissue. These basal potentials reflected mostly the potential of the xylem, which extended into the elongating tissues. Thus, the high basal potential confirmed the high potential near the xylem in the elongating tissues. The psychrometer measurements for each tissue gave average potentials that agreed with the average of the cell potentials from the pressure probe. We conclude that a radial gradient was present in the elongating region that formed a water potential field in three dimensions around the xylem and that confirmed the predictions of Molz and Boyer (F.J. Molz and J.S. Boyer [1978] Plant Physiol 62: 423-429).

Direct Demonstration of a Growth-Induced Water Potential Gradient.

PubMed Central

Nonami, H.; Boyer, J. S.

1993-01-01

When transpiration is negligible, water potentials in growing tissues are less than those in mature tissues and have been predicted to form gradients that move water into the enlarging cells. To determine directly whether the gradients exist, we measured water potentials along the radius of stems of intact soybean (Glycine max [L.] Merr.) seedlings growing in vermiculite in a water-saturated atmosphere. The measurements were made in individual cells by first determining the turgor with a miniature pressure probe, then determining the osmotic potential of solution from the same cell, and finally summing the two potentials. The osmotic potentials were corrected for sample mixing in the probe. The measurements were checked with a thermocouple psychrometer that gave average tissue water potentials. In the elongating region, the water potential was highest near the xylem and lowest near the epidermis and in the center of the pith. In the basal, more mature region of the same stems, water potentials were near zero next to the xylem and throughout the tissue. These basal potentials reflected mostly the potential of the xylem, which extended into the elongating tissues. Thus, the high basal potential confirmed the high potential near the xylem in the elongating tissues. The psychrometer measurements for each tissue gave average potentials that agreed with the average of the cell potentials from the pressure probe. We conclude that a radial gradient was present in the elongating region that formed a water potential field in three dimensions around the xylem and that confirmed the predictions of Molz and Boyer (F.J. Molz and J.S. Boyer [1978] Plant Physiol 62: 423-429). PMID:12231794

Rainwater harvesting to enhance water productivity of rainfed agriculture in the semi-arid Zimbabwe

NASA Astrophysics Data System (ADS)

Kahinda, Jean-marc Mwenge; Rockström, Johan; Taigbenu, Akpofure E.; Dimes, John

Zimbabwe’s poor are predominantly located in the semi-arid regions and rely on rainfed agriculture for their subsistence. Decline in productivity, scarcity of arable land, irrigation expansion limitations, erratic rainfall and frequent dry spells, among others cause food scarcity. The challenge faced by small-scale farmers is to enhance water productivity of rainfed agriculture by mitigating intra-seasonal dry spells (ISDS) through the adoption of new technologies such as rainwater harvesting (RWH). The paper analyses the agro-hydrological functions of RWH and assesses its impacts (at field scale) on the crop yield gap as well as the Transpirational Water Productivity ( WPT). The survey in six districts of the semi-arid Zimbabwe suggests that three parameters (water source, primary use and storage capacity) can help differentiate storage-type-RWH systems from “conventional dams”. The Agricultural Production Simulator Model (APSIM) was used to simulate seven different treatments (Control, RWH, Manure, Manure + RWH, Inorganic Nitrogen and Inorganic Nitrogen + RWH) for 30 years on alfisol deep sand, assuming no fertiliser carry over effect from season to season. The combined use of inorganic fertiliser and RWH is the only treatment that closes the yield gap. Supplemental irrigation alone not only reduces the risks of complete crop failure (from 20% down to 7% on average) for all the treatments but also enhances WPT (from 1.75 kg m -3 up to 2.3 kg m -3 on average) by mitigating ISDS.

Energy Harvesting & Recapture from Human Subjects: Dual-Stage MEMS Cantilever Energy Harvester

DTIC Science & Technology

2015-03-01

15 Figure 5. (a) In-plane overlap-varying capacitive harvester, (b) In-plane gap-closing capacitive harvester, (c) Out -of-plane gap-closing...capacitive harvester, (c) Out -of-plane gap-closing capacitive harvester [1] The two-way arrows in each subpart of Figure 5 indicate the shuttle’s direction...are compatible with other wafer -based technologies. Bismuth Telluride (Bi2Te3), a common Seebeck thermoelectric material, is able to be processed

Potential Impact of Submarine Power Cables on Crab Harvest

NASA Astrophysics Data System (ADS)

Bull, A. S.; Nishimoto, M.

2016-02-01

Offshore renewable energy installations convert wave or wind energy to electricity and transfer the power to shore through transmission cables laid on or buried beneath the seafloor. West coast commercial fishermen, who harvest the highly prized Dungeness crab (Metacarcinus magister) and the rock crab (Cancer spp.), are concerned that the interface of crabs and electromagnetic fields (EMF) from these cables will present an electrified fence on the seafloor that their target resource will not cross. Combined with the assistance of professional fishermen, submarine transmission cables that electrify island communities and offshore oil platforms in the eastern Pacific provide an opportunity to test the harvest of crab species across power transmission cables. In situ field techniques give commercial crab species a choice to decide if they will cross fully energized, EMF emitting, power transmission cables, in response to baited traps. Each independent trial is either one of two possible responses: the crab crosses the cable to enter a trap (1) or the crab does not cross the cable to enter a trap (0). Conditions vary among sample units by the following categorical, fixed factors (i.e., covariates) of cable structure (buried or unburied); direction of cable from crab position (west or east, north or south); time and season. A generalized linear model is fit to the data to determine whether any of these factors affect the probability of crabs crossing an energized cable to enter baited traps. Additionally, the experimental design, aside from the number of runs (set of sample trials) and the dates of the runs, is the same in the Santa Barbara Channel for rock crab and Puget Sound for Dungeness crab, and allows us to compare the capture rates of the two species in the two areas. We present preliminary results from field testing in 2015.

77 FR 58731 - Migratory Bird Subsistence Harvest in Alaska; Harvest Regulations for Migratory Birds in Alaska...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-21

... partners, developed measures in 2009 to further reduce the potential for shooting mortality or injury of... conservation via the bird fair, meetings, radio shows, signs, school visits, and one-on-one contacts. We also... of the harvest. Our primary strategy to reduce the threat of shooting mortality of threatened eiders...

1976 Oregon timber harvest.

Treesearch

J.D. Jr. Lloyd

1978-01-01

The 1976 Oregon timber harvest of 8.15 billion board feet ended a 3-year decline. The cut was 783 million board feet (10.6 percent) above the 1975 harvest. The western Oregon harvest rose 812 million board feet (15 percent) while eastern Oregon declined 29 million board feet (15 percent). The proportion of total harvest which comes from eastern Oregon has gradually...

Influences of harvesting on functions of floodplain forests associated with low-order, blackwater streams

Treesearch

B.G. Lockaby; R.H. Jones; R.G. Clawson; J.S. Meadows; John A. Stanturf; F.C. Thornton

1997-01-01

The influence of both aerial and ground-based harvesting on functions of forested floodplains of low-order streams was studied during a two-year period. The study sites were associated with low-order, blackwater streams with infertile and primarily organic soils. Responses to harvesting were assessed in relation to water quality, denitrification, hydrology,...

Endocardial Energy Harvesting by Electromagnetic Induction.

PubMed

Zurbuchen, Adrian; Haeberlin, Andreas; Bereuter, Lukas; Pfenniger, Alois; Bosshard, Simon; Kernen, Micha; Philipp Heinisch, Paul; Fuhrer, Juerg; Vogel, Rolf

2018-02-01

cardiac pacemakers require regular medical follow-ups to ensure proper functioning. However, device replacements due to battery depletion are common and account for ∼25% of all implantation procedures. Furthermore, conventional pacemakers require pacemaker leads which are prone to fractures, dislocations or isolation defects. The ensuing surgical interventions increase risks for the patients and costs that need to be avoided. in this study, we present a method to harvest energy from endocardial heart motions. We developed a novel generator, which converts the heart's mechanical into electrical energy by electromagnetic induction. A mathematical model has been introduced to identify design parameters strongly related to the energy conversion efficiency of heart motions and fit the geometrical constraints for a miniaturized transcatheter deployable device. The implemented final design was tested on the bench and in vivo. the mathematical model proved an accurate method to estimate the harvested energy. For three previously recorded heart motions, the model predicted a mean output power of 14.5, 41.9, and 16.9 μW. During an animal experiment, the implanted device harvested a mean output power of 0.78 and 1.7 μW at a heart rate of 84 and 160 bpm, respectively. harvesting kinetic energy from endocardial motions seems feasible. Implanted at an energetically favorable location, such systems might become a welcome alternative to extend the lifetime of cardiac implantable electronic device. the presented endocardial energy harvesting concept has the potential to turn pacemakers into battery- and leadless systems and thereby eliminate two major drawbacks of contemporary systems.

Principles of thermoacoustic energy harvesting

NASA Astrophysics Data System (ADS)

Avent, A. W.; Bowen, C. R.

2015-11-01

Thermoacoustics exploit a temperature gradient to produce powerful acoustic pressure waves. The technology has a key role to play in energy harvesting systems. A time-line in the development of thermoacoustics is presented from its earliest recorded example in glass blowing through to the development of the Sondhauss and Rijke tubes to Stirling engines and pulse-tube cryo-cooling. The review sets the current literature in context, identifies key publications and promising areas of research. The fundamental principles of thermoacoustic phenomena are explained; design challenges and factors influencing efficiency are explored. Thermoacoustic processes involve complex multi-physical coupling and transient, highly non-linear relationships which are computationally expensive to model; appropriate numerical modelling techniques and options for analyses are presented. Potential methods of harvesting the energy in the acoustic waves are also examined.

Clean Water State Revolving Fund (CWSRF): Water Conservation

EPA Pesticide Factsheets

The CWSRF can provide financial assistance for water conservation projects that reduce the demand for POTW capacity through reduced water consumption (i.e., water efficiency), as well as water reuse and precipitation harvesting.

Designing domestic rainwater harvesting systems under different climatic regimes in Italy.

PubMed

Campisano, A; Gnecco, I; Modica, C; Palla, A

2013-01-01

Nowadays domestic rainwater harvesting practices are recognized as effective tools to improve the sustainability of drainage systems within the urban environment, by contributing to limiting the demand for potable water and, at the same time, by mitigating the generation of storm water runoff at the source. The final objective of this paper is to define regression curves to size domestic rainwater harvesting (DRWH) systems in the main Italian climatic regions. For this purpose, the Köppen-Geiger climatic classification is used and, furthermore, suitable precipitation sites are selected for each climatic region. A behavioural model is implemented to assess inflow, outflow and change in storage volume of a rainwater harvesting system according to daily mass balance simulations based on historical rainfall observations. The performance of the DRWH system under various climate and operational conditions is examined as a function of two non-dimensional parameters, namely the demand fraction (d) and the modified storage fraction (sm). This last parameter allowed the evaluation of the effects of the rainfall intra-annual variability on the system performance.

A New Technique for Conchal Cartilage Harvest.

PubMed

Kim, Joon Young; Yang, Ho Jik; Jeong, Ji Won

2017-03-01

The goal of auricular cartilage harvest is to obtain a sufficient amount for reconstruction and to minimize the change in ear shape. The cartilage can be harvested by a posterior or anterior approach, and each method has advantages and disadvantages. The posterior approach presents the advantage of scar concealment, but there are limits to the amount of cymba cartilage that may be harvested. In contrast, the anterior approach may cause a noticeable scar. However, as cartilage is collected, the anterior approach provides a view that facilitates the preservation ear structure. In addition, it is possible to obtain a greater amount of cartilage. From January 2014 to December 2015, we harvested auricular cartilage graft material in 17 patients. To prevent the development of trapdoor scars or linear scar contracture, short incisions were made on the superior border of the cymba and cavum. Two small and narrow incisions were made, resulting in suboptimal exposure of the surgical site, which heightens the potential for damaging the cartilage when using existing tools. To minimize this, the authors used a newly invented ball-type elevator. All patients recovered without complications after surgery and reported satisfaction with the shape of the ear.

A New Technique for Conchal Cartilage Harvest

PubMed Central

Kim, Joon Young; Jeong, Ji Won

2017-01-01

The goal of auricular cartilage harvest is to obtain a sufficient amount for reconstruction and to minimize the change in ear shape. The cartilage can be harvested by a posterior or anterior approach, and each method has advantages and disadvantages. The posterior approach presents the advantage of scar concealment, but there are limits to the amount of cymba cartilage that may be harvested. In contrast, the anterior approach may cause a noticeable scar. However, as cartilage is collected, the anterior approach provides a view that facilitates the preservation ear structure. In addition, it is possible to obtain a greater amount of cartilage. From January 2014 to December 2015, we harvested auricular cartilage graft material in 17 patients. To prevent the development of trapdoor scars or linear scar contracture, short incisions were made on the superior border of the cymba and cavum. Two small and narrow incisions were made, resulting in suboptimal exposure of the surgical site, which heightens the potential for damaging the cartilage when using existing tools. To minimize this, the authors used a newly invented ball-type elevator. All patients recovered without complications after surgery and reported satisfaction with the shape of the ear. PMID:28352607

1974 Oregon timber harvest.

Treesearch

J.D. Jr. Lloyd

1976-01-01

The 1974 Oregon timber harvest of 8.36 billion board feet was 9.2 percent, or 0.84 billion board feet, below the 1973 harvest. (The data for 1973 were adjusted to reflect the change in reporting of harvest on Bureau of Land Management lands; see footnote 3 of table.) While the harvest in western Oregon decreased 14.7 percent, eastern Oregon cut increased 11.5 percent...

Optimal design of permeable fiber network structures for fog harvesting.

PubMed

Park, Kyoo-Chul; Chhatre, Shreerang S; Srinivasan, Siddarth; Cohen, Robert E; McKinley, Gareth H

2013-10-29

Fog represents a large untapped source of potable water, especially in arid climates. Numerous plants and animals use textural and chemical features on their surfaces to harvest this precious resource. In this work, we investigate the influence of the surface wettability characteristics, length scale, and weave density on the fog-harvesting capability of woven meshes. We develop a combined hydrodynamic and surface wettability model to predict the overall fog-collection efficiency of the meshes and cast the findings in the form of a design chart. Two limiting surface wettability constraints govern the re-entrainment of collected droplets and clogging of mesh openings. Appropriate tuning of the wetting characteristics of the surfaces, reducing the wire radii, and optimizing the wire spacing all lead to more efficient fog collection. We use a family of coated meshes with a directed stream of fog droplets to simulate a natural foggy environment and demonstrate a five-fold enhancement in the fog-collecting efficiency of a conventional polyolefin mesh. The design rules developed in this work can be applied to select a mesh surface with optimal topography and wetting characteristics to harvest enhanced water fluxes over a wide range of natural convected fog environments.

Analog self-powered harvester achieving switching pause control to increase harvested energy

NASA Astrophysics Data System (ADS)

Makihara, Kanjuro; Asahina, Kei

2017-05-01

In this paper, we propose a self-powered analog controller circuit to increase the efficiency of electrical energy harvesting from vibrational energy using piezoelectric materials. Although the existing synchronized switch harvesting on inductor (SSHI) method is designed to produce efficient harvesting, its switching operation generates a vibration-suppression effect that reduces the harvested levels of electrical energy. To solve this problem, the authors proposed—in a previous paper—a switching method that takes this vibration-suppression effect into account. This method temporarily pauses the switching operation, allowing the recovery of the mechanical displacement and, therefore, of the piezoelectric voltage. In this paper, we propose a self-powered analog circuit to implement this switching control method. Self-powered vibration harvesting is achieved in this study by attaching a newly designed circuit to an existing analog controller for SSHI. This circuit aims to effectively implement the aforementioned new switching control strategy, where switching is paused in some vibration peaks, in order to allow motion recovery and a consequent increase in the harvested energy. Harvesting experiments performed using the proposed circuit reveal that the proposed method can increase the energy stored in the storage capacitor by a factor of 8.5 relative to the conventional SSHI circuit. This proposed technique is useful to increase the harvested energy especially for piezoelectric systems having large coupling factor.

Metrics Proposed To Prevent the Harvest of Leafy Green Crops Exposed to Floodwater Contaminated with Escherichia coli.

PubMed

Callahan, Mary Theresa; Micallef, Shirley A; Sharma, Manan; Millner, Patricia D; Buchanan, Robert L

2016-07-01

The California Leafy Green Products Handler Marketing Agreement (LGMA) requires leafy green crops within 9 m of the edge of a flooded field not be harvested due to potential contamination (California Leafy Green Products Handler Marketing Board, Commodity Specific Flood Safety Guidelines for the Production and Harvest of Lettuce and Leafy Greens, 2012). Further, previously flooded soils should not be replanted for 60 days. In this study, the suitability of the LGMA metrics for farms in the Mid-Atlantic region of the United States was evaluated. The upper end of a spinach bed (in Beltsville, MD) established on a -5% grade was flooded with water containing 6 log CFU/ml Escherichia coli to model a worst-case scenario of bacterial movement through soil. Escherichia coli prevalence in soil and on foliar tissue was determined by most probable number (MPN) analysis at distances up to 9 m from the edge of the flood for 63 days. While E. coli was quickly detected at the 9-m distance within 1 day in the spring trial and within 3 days in the fall trial, no E. coli was detected on plants outside the flood zone after 14 days. On day 63 for the two trials, E. coli populations in the flood zone soil were higher in the fall than in the spring. Regression analysis predicted that the time required for a 3-log MPN/g (dry weight) decrease in E. coli populations inside the flood zone was within the 60-day LGMA guideline in the spring but would require 90 days in the fall. Overall, data suggest that the current guidelines should be revised to include considerations of field and weather conditions that may promote bacterial movement and survival. This study tracked the movement of Escherichia coli from floodwater across a horizontal plane of soil and the potential for the contamination of distant leafy green produce. The purpose of this study was to address the validity of the California Leafy Green Products Handler Marketing Agreement recommendations for the harvest of leafy green crops

Metrics Proposed To Prevent the Harvest of Leafy Green Crops Exposed to Floodwater Contaminated with Escherichia coli

PubMed Central

Callahan, Mary Theresa; Micallef, Shirley A.; Sharma, Manan; Millner, Patricia D.

2016-01-01

ABSTRACT The California Leafy Green Products Handler Marketing Agreement (LGMA) requires leafy green crops within 9 m of the edge of a flooded field not be harvested due to potential contamination (California Leafy Green Products Handler Marketing Board, Commodity Specific Flood Safety Guidelines for the Production and Harvest of Lettuce and Leafy Greens, 2012). Further, previously flooded soils should not be replanted for 60 days. In this study, the suitability of the LGMA metrics for farms in the Mid-Atlantic region of the United States was evaluated. The upper end of a spinach bed (in Beltsville, MD) established on a −5% grade was flooded with water containing 6 log CFU/ml Escherichia coli to model a worst-case scenario of bacterial movement through soil. Escherichia coli prevalence in soil and on foliar tissue was determined by most probable number (MPN) analysis at distances up to 9 m from the edge of the flood for 63 days. While E. coli was quickly detected at the 9-m distance within 1 day in the spring trial and within 3 days in the fall trial, no E. coli was detected on plants outside the flood zone after 14 days. On day 63 for the two trials, E. coli populations in the flood zone soil were higher in the fall than in the spring. Regression analysis predicted that the time required for a 3-log MPN/g (dry weight) decrease in E. coli populations inside the flood zone was within the 60-day LGMA guideline in the spring but would require 90 days in the fall. Overall, data suggest that the current guidelines should be revised to include considerations of field and weather conditions that may promote bacterial movement and survival. IMPORTANCE This study tracked the movement of Escherichia coli from floodwater across a horizontal plane of soil and the potential for the contamination of distant leafy green produce. The purpose of this study was to address the validity of the California Leafy Green Products Handler Marketing Agreement recommendations for the

Long-term implications of forest harvesting on nutrient cycling in central hardwood forests

Treesearch

J.A. Lynch; E.S. Corbett

1991-01-01

Fourteen years of streamflow and water quality data from the Leading Ridge Experimental Watersheds in central Pennsylvania were analyzed to determine the long-term impacts of a commercial forest harvest on stream water chemistry and nutrient loss.

Simulating the environmental performance of post-harvest management measures to comply with the EU Nitrates Directive.

PubMed

De Waele, J; D'Haene, K; Salomez, J; Hofman, G; De Neve, S

2017-02-01

Nitrate (NO 3 - ) leaching from farmland remains the predominant source of nitrogen (N) loads to European ground- and surface water. As soil mineral N content at harvest is often high and may increase by mineralisation from crop residues and soil organic matter, it is critical to understand which post-harvest management measures can be taken to restrict the average NO 3 - concentration in ground- and surface waters below the norm of 50 mg l -1 . Nitrate leaching was simulated with the EU-rotate_N model on a silty and a sandy soil following the five main arable crops cultivated in Flanders: cut grassland, silage maize, potatoes, sugar beets and winter wheat, in scenarios of optimum fertilisation with and without post-harvest measures. We compared the average NO 3 - concentration in the leaching water at a depth of 90 cm in these scenarios after dividing it by a factor of 2.1 to include natural attenuation processes occurring during transport towards ground- and surface water. For cut grassland, the average attenuated NO 3 - concentration remained below the norm on both soils. In order to comply with the Nitrates Directive, post-harvest measures seemed to be necessary on sandy soils for the four other crops and on silty soils for silage maize and for potatoes. Successful measures appeared to be the early sowing of winter crops after harvesting winter wheat, the undersowing of grass in silage maize and the removal of sugar beet leaves. Potatoes remained a problematic crop as N uptake by winter crops was insufficient to prevent excessive NO 3 - leaching. For each crop, maximum levels of soil mineral N content at harvest were proposed, both with and without additional measures, which could be used in future nutrient legislation. The approach taken here could be upscaled from the field level to the subcatchment level to see how different crops could be arranged within a subcatchment to permit the cultivation of problem crops without adversely affecting the water

Toward a semi-mechanical harvesting platform system for harvesting blueberries with fresh-market quality

USDA-ARS?s Scientific Manuscript database

Major concerns related to harvesting blueberries for fresh market with over-the-row (OTR) harvesters are that the quality of the fruit harvested with OTR machines is generally low and ground loss is excessive. Machine-harvested blueberries have more internal bruise and usually soften rapidly in col...

Financial feasibility of end-user designed rainwater harvesting and greywater reuse systems for high water use households.

PubMed

Oviedo-Ocaña, Edgar Ricardo; Dominguez, Isabel; Ward, Sarah; Rivera-Sanchez, Miryam Lizeth; Zaraza-Peña, Julian Mauricio

2017-03-30

Water availability pressures, competing end-uses and sewers at capacity are all drivers for change in urban water management. Rainwater harvesting (RWH) and greywater reuse (GWR) systems constitute alternatives to reduce drinking water usage and in the case of RWH, reduce roof runoff entering sewers. Despite the increasing popularity of installations in commercial buildings, RWH and GWR technologies at a household scale have proved less popular, across a range of global contexts. For systems designed from the top-down, this is often due to the lack of a favourable cost-benefit (where subsidies are unavailable), though few studies have focused on performing full capital and operational financial assessments, particularly in high water consumption households. Using a bottom-up design approach, based on a questionnaire survey with 35 households in a residential complex in Bucaramanga, Colombia, this article considers the initial financial feasibility of three RWH and GWR system configurations proposed for high water using households (equivalent to >203 L per capita per day). A full capital and operational financial assessment was performed at a more detailed level for the most viable design using historic rainfall data. For the selected configuration ('Alt 2'), the estimated potable water saving was 44% (equivalent to 131 m 3 /year) with a rate of return on investment of 6.5% and an estimated payback period of 23 years. As an initial end-user-driven design exercise, these results are promising and constitute a starting point for facilitating such approaches to urban water management at the household scale.

Response of Leaf Water Potential, Stomatal Resistance, and Leaf Rolling to Water Stress

PubMed Central

O'Toole, John C.; Cruz, Rolando T.

1980-01-01

Numerous studies have associated increased stomatal resistance with response to water deficit in cereals. However, consideration of change in leaf form seems to have been neglected. The response of adaxial and abaxial stomatal resistance and leaf rolling in rice to decreasing leaf water potential was investigated. Two rice cultivars were subjected to control and water stress treatments in a deep (1-meter) aerobic soil. Concurrent measurements of leaf water potential, stomatal resistance, and degree of leaf rolling were made through a 29-day period after cessation of irrigation. Kinandang Patong, an upland adapted cultivar, maintained higher dawn and midday leaf water potential than IR28, a hybrid selected in irrigated conditions. This was not explained by differences in leaf diffusive resistance or leaf rolling, and is assumed to result from a difference in root system extent. Stomatal resistance increased more on the abaxial than the adaxial leaf surface in both cultivars. This was associated with a change in leaf form or rolling inward of the upper leaf surface. Both responses, increased stomatal resistance and leaf rolling, were initiated in a similar leaf water potential range (−8 to −12 bars). Leaves of IR28 became fully rolled at leaf water potential of about −22 bars; however, total leaf diffusive resistance was only about 4 to 5 seconds per centimeter (conductance 0.25 to 0.2 centimeter per second) at that stage. Leaf diffusive resistance and degree of leaf rolling were linearly related to leaf water potential. Thus, leaf rolling in rice may be used as an estimate of the other two less obvious effects of water deficit. PMID:16661206

Stump Harvesting

Treesearch

Dana Mitchell

2009-01-01

Increased use of forest fuel requires larger and larger procurement areas. Inclusion of stump material within the shorter distances could make this unusual source of biomass more economical to harvest. Land clearing activities are also helping to raise interest in stump harvesting. Processing stump material for biomass is an alternative...

Long-term effects of timber harvesting on forest soil communities and their catabolic capacity

NASA Astrophysics Data System (ADS)

Mohn, W. W.

2016-12-01

We examined the effect of forest harvesting on metagenomes of soil communities in ecozones across North America. The overall effect of harvesting on community composition was very small relative to major differences between soil horizons and among geographically distinct ecozones. However, in some ecozones, harvesting substantially altered bacterial and fungal community composition and diminished the genetic potential for biomass decomposition while increasing the potential for nitrogen cycling. Stable isotope probing identified populations involved in hemicellulose and cellulose decomposition. Known cellulolytic organisms were found in the organic soil layer, while novel cellulolytic organisms were identified in the mineral soil layer. Lignolytic populations identified were mainly bacterial, and metagenomics analysis identified lignin degradation enzymes in the genomes of some of these populations. In some ecozones, cellulolytic and hemicellulolytic populations were substantially impacted by harvesting. Soil carbon, nitrogen and pH were related to the relative susceptibility of forest soil communities in the different ecozones to harvesting impacts.

Human-induced evolution caused by unnatural selection through harvest of wild animals

PubMed Central

Allendorf, Fred W.; Hard, Jeffrey J.

2009-01-01

Human harvest of phenotypically desirable animals from wild populations imposes selection that can reduce the frequencies of those desirable phenotypes. Hunting and fishing contrast with agricultural and aquacultural practices in which the most desirable animals are typically bred with the specific goal of increasing the frequency of desirable phenotypes. We consider the potential effects of harvest on the genetics and sustainability of wild populations. We also consider how harvesting could affect the mating system and thereby modify sexual selection in a way that might affect recruitment. Determining whether phenotypic changes in harvested populations are due to evolution, rather than phenotypic plasticity or environmental variation, has been problematic. Nevertheless, it is likely that some undesirable changes observed over time in exploited populations (e.g., reduced body size, earlier sexual maturity, reduced antler size, etc.) are due to selection against desirable phenotypes—a process we call “unnatural” selection. Evolution brought about by human harvest might greatly increase the time required for over-harvested populations to recover once harvest is curtailed because harvesting often creates strong selection differentials, whereas curtailing harvest will often result in less intense selection in the opposing direction. We strongly encourage those responsible for managing harvested wild populations to take into account possible selective effects of harvest management and to implement monitoring programs to detect exploitation-induced selection before it seriously impacts viability. PMID:19528656

Identification of Suitable Water Harvesting Zones Based on Geomorphic Resources for Drought Areas: A Case Study of Una District, Himachal Pradesh, India.

NASA Astrophysics Data System (ADS)

Prakasam, D. C., Jr.; Zaman, B.

2014-12-01

Water is one of the most vital natural resource and its availability and quality determine ecosystem productivity, both for agricultural and natural systems. Una district is one of the major potential agricultural districts in Himachal Pradesh, India. More than 70% of the population of this district is engaged in agriculture and allied sectors and major crops grown are maize, wheat, rice, sugarcane, pulses and vegetables. The region faces drought every year and about 90 per cent of the area is water stressed. This has resulted in crop loss and shortage of food and fodder. The sources of drinking water, small ponds and bowlies dry-up during summer season resulting in scarcity of drinking water. Una district receives rainfall during monsoons from June to September and also during non-monsoon period (winter). The annual average rainfall in the area is about 1040 mm with 55 average rainy days. But due to heavy surface run-off the farmers not able to cultivate the crops more than once in a year. Past research indicate that the geomorphology of the Una district might be responsible for such droughts as it controls the surface as well as ground water resources. The research proposes to develop a water stress model for Una district using the geomorphic parameters, water resource and land use land cover data of the study area. Using Survey of India topographical maps (1:50000), the geomorphic parameters are extracted. The spatial layers of these parameters i.e. drainage density, slope, relative relief, ruggedness index, surface water body's frequency are created in GIS. A time series of normalized remotely sensed data of the study area is used for land use land cover classification and analyses. Based on the results from the water stress model, the drought/water stress areas and water harvesting zones are identified and documented. The results of this research will help the general population in resolving the drinking water problem to a certain extent and also the

Solubility of methane in water: the significance of the methane-water interaction potential.

PubMed

Konrad, Oliver; Lankau, Timm

2005-12-15

The influence of the methane-water interaction potential on the value of the Henry constant obtained from molecular dynamics simulations was investigated. The SPC, SPC/E, MSPC/E, and TIP3P potentials were used to describe water and the OPLS-UA and TraPPE potentials for methane. Nonbonding interactions between unlike atoms were calculated both with one of four mixing rules and with our new methane-water interaction potential. The Henry constants obtained from simulations using any of the mixing rules differed significantly from the experimental ones. Good agreement between simulation and experiment was achieved with the new potential over the whole temperature range.

Harvest impacts in uneven-aged and even-aged Missouri Ozark forests

Treesearch

John P. Dwyer; Daniel C. Dey; William D. Walter; Randy G. Jensen

2004-01-01

Forest managers are concerned about the potential damage to residual trees and site from cyclic harvest re-entries into the same forest stand. This study summarizes logging and felling damage resulting from the harvesting of silvicultural treatments on a large landscape experiment in southern Missouri that is designed to compare impacts of even-aged, uneven-aged and no...

Snag density varies with intensity of timber harvest and human access

Treesearch

Michael J. Wisdom; Lisa J. Bate

2008-01-01

Many species of vertebrates depend on snags (standing dead trees) for persistence, and limited research suggests that snag density is lower in areas of intensive timber harvest and increased human access. While intensive timber harvest is one source of potential snag loss, ease of human access to forest stands may also facilitate loss via firewood cutting of snags....

Thermoresponsive electrospun fibers for water harvesting applications

NASA Astrophysics Data System (ADS)

Thakur, Neha; Baji, Avinash; Ranganath, Anupama Sargur

2018-03-01

Temperature triggered switchable cellulose acetate-poly(N-isopropylacrylamide) (CA-PNIPAM) core-shell and blend nanofibers are fabricated for controlled moisture harvesting applications. Core-shell fibers are fabricated using a co-axial electrospinning setup whereas the conventional electrospinning setup is employed for fabricating the blend fibers. Investigation of their wettability behaviour demonstrated that the blend fibers are superhydrophilic whereas the core-shell fibers are hydrophilic at ambient temperature. Furthermore, both the samples have an ability to switch between the two states viz. hydrophilic to hydrophobic state based on thermal stimulus. The core-shell fibers are shown to have higher moisture sorption ability compared to the blend fibers. This study investigates the mechanism behind the switchable wettability behaviour of the core-shell fibers and demonstrates the crucial role played by the functional groups present on the surface layer of fibers in governing their moisture collection efficiency.

Self-Powered Viscosity and Pressure Sensing in Microfluidic Systems Based on the Piezoelectric Energy Harvesting of Flowing Droplets.

PubMed

Wang, Zhao; Tan, Lun; Pan, Xumin; Liu, Gao; He, Yahua; Jin, Wenchao; Li, Meng; Hu, Yongming; Gu, Haoshuang

2017-08-30

The rapid development of microscaled piezoelectric energy harvesters has provided a simple and highly efficient way for building self-powered sensor systems through harvesting the mechanical energy from the ambient environment. In this work, a self-powered microfluidic sensor that can harvest the mechanical energy of the fluid and simultaneously monitor their characteristics was fabricated by integrating the flexible piezoelectric poly(vinylidene fluoride) (PVDF) nanofibers with the well-designed microfluidic chips. Those devices could generate open-circuit high output voltage up to 1.8 V when a droplet of water is flowing past the suspended PVDF nanofibers and result in their periodical deformations. The impulsive output voltage signal allowed them to be utilized for droplets or bubbles counting in the microfluidic systems. Furthermore, the devices also exhibited self-powered sensing behavior due to the decreased voltage amplitude with increasing input pressure and liquid viscosity. The drop of output voltage could be attributed to the variation of flow condition and velocity of the droplets, leading to the reduced deformation of the piezoelectric PVDF layer and the decrease of the generated piezoelectric potential.

Triboelectric nanogenerator built on suspended 3D spiral structure as vibration and positioning sensor and wave energy harvester.

PubMed

Hu, Youfan; Yang, Jin; Jing, Qingshen; Niu, Simiao; Wu, Wenzhuo; Wang, Zhong Lin

2013-11-26

An unstable mechanical structure that can self-balance when perturbed is a superior choice for vibration energy harvesting and vibration detection. In this work, a suspended 3D spiral structure is integrated with a triboelectric nanogenerator (TENG) for energy harvesting and sensor applications. The newly designed vertical contact-separation mode TENG has a wide working bandwidth of 30 Hz in low-frequency range with a maximum output power density of 2.76 W/m(2) on a load of 6 MΩ. The position of an in-plane vibration source was identified by placing TENGs at multiple positions as multichannel, self-powered active sensors, and the location of the vibration source was determined with an error less than 6%. The magnitude of the vibration is also measured by the output voltage and current signal of the TENG. By integrating the TENG inside a buoy ball, wave energy harvesting at water surface has been demonstrated and used for lighting illumination light, which shows great potential applications in marine science and environmental/infrastructure monitoring.

Cities as Water Supply Catchments to deliver microclimate benefits

NASA Astrophysics Data System (ADS)

Beringer, J.; Tapper, N. J.; Coutts, A.; Loughnan, M.

2010-12-01

Urban development extensively modifies the natural hydrology, biodiversity, carbon balance, air quality and climate of the local and regional environment mainly due to increased impervious surface area (roads, pavements, roofs, etc.). Impervious surface are a legacy of urban infrastructure planning based on a ‘drained city’ to minimise flood risk. The result is a modification of the microclimate around buildings and on a city scale results in the Urban Heat Island (UHI) effect where the urban areas are much hotter than the surrounding rural areas. Such heating comes on top of 20th century human induced climate change, namely decreased rainfall and higher temperatures. Drought conditions have triggered water restrictions in many Australian cities that have dramatically reduced ‘irrigation’ in urban areas. Ironically the drying influence from climate change has now been compounded by the drying influence of water restrictions and the efficient removal of stormwater resulting in desert like climates during summer. This will be further exacerbated by the projected increases in hot days, extreme hot days, heat waves, etc. In turn this excessive heating will compromise the health and liveability of urban dwellers. Stormwater is a potential critical resource that could be used to keep water in the landscape to irrigate urban areas to improve urban micro-climates, sustain vegetation and provide other multiple benefits to create more liveable and resilient urban environments. In Australia's major cities, stormwater harvesting has the potential to provide a low cost, low energy, fit-for-purpose source of water to help secure city supplies. Stormwater reuse not only provides a potential mitigation tool for the UHI and global climate change but has multiple benefits to provide resilience such as 1) Improved human thermal comfort to reduce heat related stress and mortality, 2) Healthy and productive vegetation and increased carbon sequestration, 3) Decreased stormwater

Portable Wind Energy Harvesters for Low-Power Applications: A Survey.

PubMed

Nabavi, Seyedfakhreddin; Zhang, Lihong

2016-07-16

Energy harvesting has become an increasingly important topic thanks to the advantages in renewability and environmental friendliness. In this paper, a comprehensive study on contemporary portable wind energy harvesters has been conducted. The electrical power generation methods of portable wind energy harvesters are surveyed in three major groups, piezoelectric-, electromagnetic-, and electrostatic-based generators. The paper also takes another view of this area by gauging the required mechanisms for trapping wind flow from ambient environment. In this regard, rotational and aeroelastic mechanisms are analyzed for the portable wind energy harvesting devices. The comparison between both mechanisms shows that the aeroelastic mechanism has promising potential in producing an energy harvester in smaller scale although how to maintain the resonator perpendicular to wind flow for collecting the maximum vibration is still a major challenge to overcome for this mechanism. Furthermore, this paper categorizes the previously published portable wind energy harvesters to macro and micro scales in terms of their physical dimensions. The power management systems are also surveyed to explore the possibility of improving energy conversion efficiency. Finally some insights and research trends are pointed out based on an overall analysis of the previously published works along the historical timeline.

Primary Events Regulating Stem Growth at Low Water Potentials 1

PubMed Central

Nonami, Hiroshi; Boyer, John S.

1990-01-01

Cell enlargement is inhibited by inadequate water. As a first step toward understanding the mechanism, all the physical parameters affecting enlargement were monitored to identify those that changed first, particularly in coincidence with the inhibition. The osmotic potential, turgor, yield threshold turgor, growth-induced water potential, wall extensibility, and conductance to water were measured in the elongating region, and the water potential was measured in the xylem of stems of dark-grown soybean (Glycine max [L.] Merr.) seedlings. A stepdown in water potential was achieved around the roots by transplanting the seedlings to vermiculite of low water content, and each of the parameters was measured simultaneously in the same plants while intact or within a few minutes of being intact using a newly developed guillotine psychrometer. The gradient of decreasing water potential from the xylem to the enlarging cells (growth-induced water potential) was the first of the parameters to decrease to a growth-limiting level. The kinetics were the same as for the inhibition of growth. The decreased gradient was caused mostly by a decreased water potential of the xylem. This was followed after 5 to 10 hours by a similar decrease in cell wall extensibility and tissue conductance for water. Later, the growth-induced water potential recovered as a result of osmotic adjustment and a rise in the water potential of the xylem. Still later, moderate growth resumed at a rate apparently determined by the low wall extensibility and tissue conductance for water. The turgor did not change significantly during the experiment. These results indicate that the primary event during the growth inhibition was the change in the growth-induced water potential. Because the growth limitation subsequently shifted to the low wall extensibility and tissue conductance for water, the initial change in potential may have set in motion subsequent metabolic changes that altered the characteristics of the

Increased water yields following harvesting operations on a drained coastal watershed

Treesearch

Johnny M. Grace; R.W. Skaggs; H.R. Malcom; G.M. Chescheir; D.K. Cassel

2003-01-01

Forest harvesting operations have been reported to affect annual and seasonal outflow characteristics from drained forest watersheds. Increases in forest outflow, nutrient concentrations, and suspended sediments are commonly seen as a result of these forest management activities. Thus, it is important to assess the impact of forest management activities on hydrology,...

Flexible piezoelectric energy harvesting from jaw movements

NASA Astrophysics Data System (ADS)

Delnavaz, Aidin; Voix, Jérémie

2014-10-01

Piezoelectric fiber composites (PFC) represent an interesting subset of smart materials that can function as sensor, actuator and energy converter. Despite their excellent potential for energy harvesting, very few PFC mechanisms have been developed to capture the human body power and convert it into an electric current to power wearable electronic devices. This paper provides a proof of concept for a head-mounted device with a PFC chin strap capable of harvesting energy from jaw movements. An electromechanical model based on the bond graph method is developed to predict the power output of the energy harvesting system. The optimum resistance value of the load and the best stretch ratio in the strap are also determined. A prototype was developed and tested and its performances were compared to the analytical model predictions. The proposed piezoelectric strap mechanism can be added to all types of head-mounted devices to power small-scale electronic devices such as hearing aids, electronic hearing protectors and communication earpieces.

Effects of feeder design and changing source of water to a location separate from the wet-dry feeder at 4 or 8 weeks before harvest on growth, feeding behavior, and carcass characteristics of finishing pigs.

PubMed

Bergstrom, J R; Nelssen, J L; Edwards, L N; Tokach, M D; Dritz, S S; Goodband, R D; DeRouchey, J M

2012-12-01

Our objectives were to compare a conventional dry (5-space, 152.4-cm-wide) and a wet-dry (double-sided, each side = 38.1-cm-wide single space) feeder and to determine if changing the source of water to a location separate from a wet-dry feeder would result in improved G:F and carcass characteristics. Water supply to the wet-dry feeder was shut off and the cup waterer was turned on in 8 pens at 8 (d 69) or 4 (d 97) wk prior to harvest. For the remaining 8 wet-dry feeder pens, the feeder provided the sole water source for the entire experiment. A total of 1,296 pigs (PIC, 337 × 1050; initially 19.4 kg BW) were used, with 27 pigs/pen (14 barrows and 13 gilts) and 24 pens/feeder design. From d 0 to 69, pigs fed with the wet-dry feeder had increased (P < 0.05) ADG, ADFI, G:F, and d 69 BW compared with those using the conventional dry feeder. Overall (d 0 to 124), pigs using fed with the water source in the wet-dry feeder the entire time had greater (P < 0.05) ADG, ADFI, final BW, and HCW the other treatments. The overall G:F was not different (P > 0.05) among pigs fed with the different feeder treatments. Pigs fed with the wet-dry feeder where water source was changed at 4 wk before harvest had greater (P < 0.05) ADG than pigs that used a conventional dry feeder. Pigs where the water source was changed at 4 wk had greater (P < 0.05) ADFI than those were the water source was changed 8 wk prior to harvest, and for pigs fed with the conventional dry feeder ADFI was intermediate. Back fat depth of pigs where the water source was changed at 8 wk before harvest was reduced (P < 0.05) compared with all other treatments and LM depth was greater (P < 0.05) than that of pigs using a conventional dry feeder and where the water source was changed at 4 week before harvest. Pigs fed using the wet-dry feeder visited the feeder less frequently (P < 0.05) and spent less total time at the feeder (P < 0.05) than those fed with the conventional dry feeder. The differences in feeding

Enhancement of Chlorella vulgaris harvesting via the electro-coagulation-flotation (ECF) method.

PubMed

Wong, Y K; Ho, Y H; Leung, H M; Ho, K C; Yau, Y H; Yung, K K L

2017-04-01

This article explores the potential of using an electro-coagulation-flotation (ECF) harvester to allow flotation of microalgae cells for surface harvesting. A response surface methodology (RSM) model was used to optimize ECF harvesting by adjusting electrode plate material, electrode plate number, charge of the electrodes, electrolyte concentration, and pH value of the culture solution. The result revealed that three aluminum electrode plates (one anode and two cathodes), brine solution (8 g/L), and acidity (pH = 4) of culture solution (optimized ECF harvester) The highest flocculant concentration was measured at 2966 mg/L after 60 min and showed a 79.8 % increase of flocculation concentration. Such results can provide a basis for designing a large-scale microalgae harvester for commercial use in the future.

A Skin-attachable Flexible Piezoelectric Pulse Wave Energy Harvester

NASA Astrophysics Data System (ADS)

Yoon, Sunghyun; Cho, Young-Ho

2014-11-01

We present a flexible piezoelectric generator, capable to harvest energy from human arterial pulse wave on the human wrist. Special features and advantages of the flexible piezoelectric generator include the multi-layer device design with contact windows and the simple fabrication process for the higher flexibility with the better energy harvesting efficiency. We have demonstrated the design effectiveness and the process simplicity of our skin- attachable flexible piezoelectric pulse wave energy harvester, composed of the sensitive P(VDF-TrFE) piezoelectric layer on the flexible polyimide support layer with windows. We experimentally characterize and demonstrate the energy harvesting capability of 0.2~1.0μW in the Human heart rate range on the skin contact area of 3.71cm2. Additional physiological and/or vital signal monitoring devices can be fabricated and integrated on the skin attachable flexible generator, covered by an insulation layer; thus demonstrating the potentials and advantages of the present device for such applications to the flexible multi-functional selfpowered artificial skins, capable to detect physiological and/or vital signals on Human skin using the energy harvested from arterial pulse waves.

Rainwater harvesting systems for low demanding applications.

PubMed

Sanches Fernandes, Luís F; Terêncio, Daniela P S; Pacheco, Fernando A L

2015-10-01

A rainwater harvesting system (RHS) was designed for a waste treatment facility located near the town of Mirandela (northern Portugal), to be used in the washing of vehicles and other equipment, the cleaning of outside concrete or asphalt floors, and the watering of green areas. Water tank volumes representing 100% efficiency (Vr) were calculated by the Ripple method with different results depending on two consumption scenarios adopted for irrigation. The RHS design was based on a precipitation record spanning a rather long period (3 decades). The calculated storage capacities fulfilled the water demand even when prolonged droughts occurred during that timeframe. However, because the drought events have been rather scarce the Vr values were considered oversized and replaced by optimal volumes. Notwithstanding the new volumes were solely half of the original Vr values, the projected RHS efficiency remained very high (around 90%) while the probability of system failure (efficiency<100%) stayed very low (in the order of 5%). In both scenarios, the economic savings related to the optimization of Vr were noteworthy, while the investment's return periods decreased substantially from the original to the optimized solutions. A high efficiency with a low storage capacity is typical of low demanding applications of rainwater harvesting, where water availability (Vw) largely exceeds water demand (Cw), that is to say where demand fractions (Cw/Vw) are very low. Based on the results of a literature review covering an ample geographic distribution and describing a very large number of demand fraction scenarios, a Cw/Vw=0.8 was defined as the threshold to generally distinguish the low from the high demanding RHS applications. Copyright © 2015 Elsevier B.V. All rights reserved.

A piezoelectric energy harvester for broadband rotational excitation using buckled beam

NASA Astrophysics Data System (ADS)

Xie, Zhengqiu; Kitio Kwuimy, C. A.; Wang, Zhiguo; Huang, Wenbin

2018-01-01

This paper proposes a rotational energy harvester using a piezoelectric bistable buckled beam to harvest low-speed rotational energy. The proposed harvester consists of a piezoelectric buckled beam with a center magnet, and a rotary magnet pair with opposite magnetic poles mounted on a revolving host. The magnetic plucking is used to harvest the angular kinetic energy of the host. The nonlinear snap-through mechanism is utilized to improve the vibration displacement and output voltage of the piezoelectric layer over a wide rotation frequency range. Theoretical simulation and experimental results show that the proposed energy harvester can yield a stable average output power ranging between 6.91-48.01 μW over a rotation frequency range of 1-14 Hz across a resistance load of 110 kΩ. Furthermore, dual attraction magnets were employed to overcome the suppression phenomenon at higher frequencies, which yields a broadband and flat frequency response over 6-14 Hz with the output power reaching 42.19-65.44 μW, demonstrating the great potential of the bistable buckled beam for wideband rotation motion energy harvesting.

INFINITY harvest

NASA Image and Video Library

2012-05-07

Lauren Lombard from Benjamin E. Mays Preparatory School in New Orleans enjoys lettuce she helped to harvest at the INFINITY at NASA Stennis Space Center facility May 7, 2012. The Louisiana students assisted in the first harvest of lettuce from the Controlled Environment Agriculture unit, which uses an aeroponic process that involves no soil and advance LED lighting techniques

Efficiency of a closed-coupled solar pasteurization system in treating roof harvested rainwater.

PubMed

Dobrowsky, P H; Carstens, M; De Villiers, J; Cloete, T E; Khan, W

2015-12-01

Many studies have concluded that roof harvested rainwater is susceptible to chemical and microbial contamination. The aim of the study was thus to conduct a preliminary investigation into the efficiency of a closed-coupled solar pasteurization system in reducing the microbiological load in harvested rainwater and to determine the change in chemical components after pasteurization. The temperature of the pasteurized tank water samples collected ranged from 55 to 57°C, 64 to 66°C, 72 to 74°C, 78 to 81°C and 90 to 91°C. Cations analyzed were within drinking water guidelines, with the exception of iron [195.59 μg/L (55°C)-170.1 μg/L (91°C)], aluminum [130.98 μg/L (78°C)], lead [12.81 μg/L (55°C)-13.2 μg/L (91°C)] and nickel [46.43 μg/L (55°C)-32.82 μg/L (78°C)], which were detected at levels above the respective guidelines in the pasteurized tank water samples. Indicator bacteria including, heterotrophic bacteria, Escherichia coli and total coliforms were reduced to below the detection limit at pasteurization temperatures of 72°C and above. However, with the use of molecular techniques Yersinia spp., Legionella spp. and Pseudomonas spp. were detected in tank water samples pasteurized at temperatures greater than 72°C. The viability of the bacteria detected in this study at the higher temperature ranges should thus be assessed before pasteurized harvested rainwater is used as a potable water source. In addition, it is recommended that the storage tank of the pasteurization system be constructed from an alternative material, other than stainless steel, in order for a closed-coupled pasteurization system to be implemented and produce large quantities of potable water from roof harvested rainwater. Copyright © 2015 Elsevier B.V. All rights reserved.

Issues in vibration energy harvesting

NASA Astrophysics Data System (ADS)

Zhang, Hui; Corr, Lawrence R.; Ma, Tianwei

2018-05-01

In this study, fundamental issues related to bandwidth and nonlinear resonance in vibrational energy harvesting devices are investigated. The results show that using bandwidth as a criterion to measure device performance can be misleading. For a linear device, an enlarged bandwidth is achieved at the cost of sacrificing device performance near resonance, and thus widening the bandwidth may offer benefits only when the natural frequency of the linear device cannot match the dominant excitation frequency. For a nonlinear device, since the principle of superposition does not apply, the ''broadband" performance improvements achieved for single-frequency excitations may not be achievable for multi-frequency excitations. It is also shown that a large-amplitude response based on the traditional ''nonlinear resonance" does not always result in the optimal performance for a nonlinear device because of the negative work done by the excitation, which indicates energy is returned back to the excitation. Such undesired negative work is eliminated at global resonance, a generalized resonant condition for both linear and nonlinear systems. While the linear resonance is a special case of global resonance for a single-frequency excitation, the maximum potential of nonlinear energy harvesting can be reached for multi-frequency excitations by using global resonance to simultaneously harvest energy distributed over multiple frequencies.

25 CFR 163.26 - Forest product harvesting permits.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 25 Indians 1 2011-04-01 2011-04-01 false Forest product harvesting permits. 163.26 Section 163.26 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS... be used by the Secretary in his or her discretion for planting or other work to offset damage to the...

Economic Impact of Harvesting Corn Stover under Time Constraint: The Case of North Dakota

DOE PAGES

Maung, Thein A.; Gustafson, Cole R.

2013-01-01

This study examines the impact of stochastic harvest field time on profit maximizing potential of corn cob/stover collection in North Dakota. Three harvest options are analyzed using mathematical programming models. Our findings show that under the first corn grain only harvest option, farmers are able to complete harvesting corn grain and achieve maximum net income in a fairly short amount of time with existing combine technology. However, under the second simultaneous corn grain and cob (one-pass) harvest option, farmers generate lower net income compared to the net income of the first option. This is due to the slowdown in combinemore » harvest capacity as a consequence of harvesting corn cobs. Under the third option of separate corn grain and stover (two-pass) harvest option, time allocation is the main challenge and our evidence shows that with limited harvest field time available, farmers find it optimal to allocate most of their time harvesting grain and then proceed to harvest and bale stover if time permits at the end of harvest season. The overall findings suggest is that it would be more economically efficient to allow a firm that is specialized in collecting biomass feedstock to participate in cob/stover harvest business.« less

Economic Impact of Harvesting Corn Stover under Time Constraint: The Case of North Dakota

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maung, Thein A.; Gustafson, Cole R.

This study examines the impact of stochastic harvest field time on profit maximizing potential of corn cob/stover collection in North Dakota. Three harvest options are analyzed using mathematical programming models. Our findings show that under the first corn grain only harvest option, farmers are able to complete harvesting corn grain and achieve maximum net income in a fairly short amount of time with existing combine technology. However, under the second simultaneous corn grain and cob (one-pass) harvest option, farmers generate lower net income compared to the net income of the first option. This is due to the slowdown in combinemore » harvest capacity as a consequence of harvesting corn cobs. Under the third option of separate corn grain and stover (two-pass) harvest option, time allocation is the main challenge and our evidence shows that with limited harvest field time available, farmers find it optimal to allocate most of their time harvesting grain and then proceed to harvest and bale stover if time permits at the end of harvest season. The overall findings suggest is that it would be more economically efficient to allow a firm that is specialized in collecting biomass feedstock to participate in cob/stover harvest business.« less

Magnetophoretic harvesting of oleaginous Chlorella sp. by using biocompatible chitosan/magnetic nanoparticle composites.

PubMed

Lee, Kyubock; Lee, So Yeun; Na, Jeong-Geol; Jeon, Sang Goo; Praveenkumar, Ramasamy; Kim, Dong-Myung; Chang, Won-Seok; Oh, You-Kwan

2013-12-01

The consumption of energy and resources such as water in the cultivation and harvesting steps should be minimized to reduce the overall cost of biodiesel production from microalgae. Here we present a biocompatible and rapid magnetophoretic harvesting process of oleaginous microalgae by using chitosan-Fe3O4 nanoparticle composites. Over 99% of microalgae was harvested by using the composites and the external magnetic field without changing the pH of culture medium so that it may be reused for microalgal culture without adverse effect on the cell growth. Depending on the working volume (20-500 mL) and the strength of surface magnetic-field (3400-9200 G), the process of harvesting microalgae took only 2-5 min. The method presented here not only utilizes permanent magnets without additional energy for fast harvesting but also recycles the medium effectively for further cultivation of microalgae, looking ahead to a large scale economic microalgae-based biorefinement. Copyright © 2013 Elsevier Ltd. All rights reserved.

Hydrologic and climatic changes in three small watersheds after timber harvest.

Treesearch

W.B. Fowler; J.D. Helvey; E.N. Felix

1987-01-01

No significant increases in annual water yield were shown for three small watersheds in northeastern Oregon after shelterwood cutting (30-percent canopy removal, 50-percent basal area removal) and clearcutting. Average maximum air temperature increased after harvest and average minimum air temperature decreased by up to 2.6 °C. Both maximum and minimum water...

Effects of harvest on the sustainability and leaf productivity of populations of two palm species in Maya homegardens.

PubMed

Martínez-Ballesté, Andrea; Martorell, Carlos

2015-01-01

Traditional management practices are usually thought to be sustainable. The Maya manage Sabal (Arecaceae) palms in homegardens, using their leaves for thatching. The sustainability of such production systems depends on the long-term persistence of palm populations, whereas resource availability also depends on the number of leaves on individual palms. We examined how leaf harvest affects Sabal yapa and S. mexicana population growth rates (λ) and leaf production, comparing traditional and alternative harvest regimes in terms of sustainability and productivity. Demographic, harvest and leaf production data were recorded for three years in two homegardens. We used general integral projection models linked to leaf-production models to describe population dynamics and productivity. Harvest had no effect on S. yapa's vital rates or on λ, but it changed the growth rate of individuals of S. mexicana, with a negligible impact on λ. Homegardens affected λ values, reflecting the species' ecological affinities. S. mexicana, introduced from mesic forests, required watering and shade; therefore, its population declined rapidly in the homegarden that lacked both water and shade. The λ of the xerophilic S. yapa was slightly larger without watering than with watering. Palms usually compensated for leaf extraction, causing the number of leaves harvested per individual to increase with harvest intensity. Nevertheless, traditional management is relatively mild, allowing standing leaves to accumulate but reducing the homegarden's yield. Apparently, the Maya do not seek to maximize annual production but to ensure the availability of large numbers of leaves in homegardens. These leaves may then be used when the entire roof of a hut needs to be replaced every few years.

Effects of Harvest on the Sustainability and Leaf Productivity of Populations of Two Palm Species in Maya Homegardens

PubMed Central

Martínez-Ballesté, Andrea; Martorell, Carlos

2015-01-01

Traditional management practices are usually thought to be sustainable. The Maya manage Sabal (Arecaceae) palms in homegardens, using their leaves for thatching. The sustainability of such production systems depends on the long-term persistence of palm populations, whereas resource availability also depends on the number of leaves on individual palms. We examined how leaf harvest affects Sabal yapa and S. mexicana population growth rates (λ) and leaf production, comparing traditional and alternative harvest regimes in terms of sustainability and productivity. Demographic, harvest and leaf production data were recorded for three years in two homegardens. We used general integral projection models linked to leaf-production models to describe population dynamics and productivity. Harvest had no effect on S. yapa’s vital rates or on λ, but it changed the growth rate of individuals of S. mexicana, with a negligible impact on λ. Homegardens affected λ values, reflecting the species’ ecological affinities. S. mexicana, introduced from mesic forests, required watering and shade; therefore, its population declined rapidly in the homegarden that lacked both water and shade. The λ of the xerophilic S. yapa was slightly larger without watering than with watering. Palms usually compensated for leaf extraction, causing the number of leaves harvested per individual to increase with harvest intensity. Nevertheless, traditional management is relatively mild, allowing standing leaves to accumulate but reducing the homegarden’s yield. Apparently, the Maya do not seek to maximize annual production but to ensure the availability of large numbers of leaves in homegardens. These leaves may then be used when the entire roof of a hut needs to be replaced every few years. PMID:25803029

1973 Oregon timber harvest.

Treesearch

J.D. Jr. Lloyd

1974-01-01

The 1973 Oregon timber harvest of 9.36 billion board feet was 265 million board feet (2.8 percent) below the 1972 harvest. The greater portion of the decrease occurred in eastern Oregon where timber harvest dropped 9.4 percent compared with 0.9 percent in western Oregon.

Characterizing the Effective Bandwidth of Nonlinear Vibratory Energy Harvesters Possessing Multiple Stable Equilibria

NASA Astrophysics Data System (ADS)

Panyam Mohan Ram, Meghashyam

In the last few years, advances in micro-fabrication technologies have lead to the development of low-power electronic devices spanning critical fields related to sensing, data transmission, and medical implants. Unfortunately, effective utilization of these devices is currently hindered by their reliance on batteries. In many of these applications, batteries may not be a viable choice as they have a fixed storage capacity and need to be constantly replaced or recharged. In light of such challenges, several novel concepts for micro-power generation have been recently introduced to harness, otherwise, wasted ambient energy from the environment and maintain these low-power devices. Vibratory energy harvesting is one such concept which has received significant attention in recent years. While linear vibratory energy harvesters have been well studied in the literature and their performance metrics have been established, recent research has focused on deliberate introduction of stiffness nonlinearities into the design of these devices. It has been shown that, nonlinear energy harvesters have a wider steady-state frequency bandwidth as compared to their linear counterparts, leading to the premise that they can used to improve performance, and decrease sensitivity to variations in the design and excitation parameters. This dissertation aims to investigate this premise by developing an analytical framework to study the influence of stiffness nonlinearities on the performance and effective bandwidth of nonlinear vibratory energy harvesters. To achieve this goal, the dissertation is divided into three parts. The first part investigates the performance of bi-stable energy harvesters possessing a symmetric quartic potential energy function under harmonic excitations and carries out a detailed analysis to define their effective frequency bandwidth. The second part investigates the relative performance of mono- and bi-stable energy harvesters under optimal electric loading

Three-dimensional hierarchical structures for fog harvesting.

PubMed

Andrews, H G; Eccles, E A; Schofield, W C E; Badyal, J P S

2011-04-05

Conventional fog-harvesting mechanisms are effectively pseudo-2D surface phenomena in terms of water droplet-plant interactions. In the case of the Cotula fallax plant, a unique hierarchical 3D arrangement formed by its leaves and the fine hairs covering them has been found to underpin the collection and retention of water droplets on the foliage for extended periods of time. The mechanisms of water capture and release as a function of the surface 3D structure and chemistry have been identified. Of particular note is that water is retained throughout the entirety of the plant and held within the foliage itself (rather than in localized regions). Individual plant hairs form matlike structures capable of supporting water droplets; these hairs wrap around water droplets in a 3D fashion to secure them via a fine nanoscale groove structure that prevents them from easily falling to the ground.

Changes in mineral-associated soil organic carbon pools across a harvested temperate forest chronosequence

NASA Astrophysics Data System (ADS)

MacIntyre, S.; Kellman, L. M.; Gabriel, C. E.; Diochon, A.

2016-12-01

Due to their substantial pool size, changes in mineral soil carbon (C) stores have the potential to generate significant changes in forest soil C budgets. Harvesting represents a significant land use disturbance that can alter soil organic carbon (SOC) stores, with a number of field studies documenting large losses of SOC following clearcut harvesting. However, little is known about how the distribution of SOC changes amongst mineral-associated pools of differing crystallinity following this disturbance. The objective of this study was to quantify changes in mineral-associated SOC pool sizes through depth and time for podzol soils (mineral soil depths of 0-5, 5-10, 10-15, 15-20, 20-35, and 35-50 cm) of a temperate red spruce harvest chronosequence (representing stand ages of 1yr, 15yr, 45yr, 80yr, and 125+yr) in Nova Scotia, Canada. Samples were subjected to a 4-step sequential chemical dissolution to selectively extract C from mineral pools of increasing crystallinity: soluble minerals (deionized water), organo-metal complexes (Na-pyrophosphate), poorly crystalline minerals (hydroxylamine), and crystalline minerals (Na-dithionite HCl). Carbon concentrations were calculated for the solutions acquired during each stage of the selective dissolution process, providing a time series of changes in mineral-associated C through depth and time following harvesting. A loss of SOC from the organo-metal complexed pool following harvesting was observed, particularly in the deeper mineral soil (20-50cm), with this pool dominating the results. In the soluble and poorly crystalline pools, losses of C were also observed from the deeper mineral soil. Of the 5 sites, the 125+yr age class had the highest concentration of SOC associated with crystalline minerals, with the 0-5cm depth stratum holding a large portion of this C. This study may be useful as a model system for understanding how harvesting disturbance alters mineral pool SOM dynamics in humid temperate forest ecosystems.

The impact of domestic rainwater harvesting systems in storm water runoff mitigation at the urban block scale.

PubMed

Palla, A; Gnecco, I; La Barbera, P

2017-04-15

In the framework of storm water management, Domestic Rainwater Harvesting (DRWH) systems are recently recognized as source control solutions according to LID principles. In order to assess the impact of these systems in storm water runoff control, a simple methodological approach is proposed. The hydrologic-hydraulic modelling is undertaken using EPA SWMM; the DRWH is implemented in the model by using a storage unit linked to the building water supply system and to the drainage network. The proposed methodology has been implemented for a residential urban block located in Genoa (Italy). Continuous simulations are performed by using the high-resolution rainfall data series for the ''do nothing'' and DRWH scenarios. The latter includes the installation of a DRWH system for each building of the urban block. Referring to the test site, the peak and volume reduction rate evaluated for the 2125 rainfall events are respectively equal to 33 and 26 percent, on average (with maximum values of 65 percent for peak and 51 percent for volume). In general, the adopted methodology indicates that the hydrologic performance of the storm water drainage network equipped with DRWH systems is noticeable even for the design storm event (T = 10 years) and the rainfall depth seems to affect the hydrologic performance at least when the total depth exceeds 20 mm. Copyright © 2017 Elsevier Ltd. All rights reserved.

Managing harvest and habitat as integrated components

USGS Publications Warehouse

Osnas, Erik; Runge, Michael C.; Mattsson, Brady J.; Austin, Jane E.; Boomer, G. S.; Clark, R. G.; Devers, P.; Eadie, J. M.; Lonsdorf, E. V.; Tavernia, Brian G.

2014-01-01

In 2007, several important initiatives in the North American waterfowl management community called for an integrated approach to habitat and harvest management. The essence of the call for integration is that harvest and habitat management affect the same resources, yet exist as separate endeavours with very different regulatory contexts. A common modelling framework could help these management streams to better understand their mutual effects. Particularly, how does successful habitat management increase harvest potential? Also, how do regional habitat programmes and large-scale harvest strategies affect continental population sizes (a metric used to express habitat goals)? In the ensuing five years, several projects took on different aspects of these challenges. While all of these projects are still on-going, and are not yet sufficiently developed to produce guidance for management decisions, they have been influential in expanding the dialogue and producing some important emerging lessons. The first lesson has been that one of the more difficult aspects of integration is not the integration across decision contexts, but the integration across spatial and temporal scales. Habitat management occurs at local and regional scales. Harvest management decisions are made at a continental scale. How do these actions, taken at different scales, combine to influence waterfowl population dynamics at all scales? The second lesson has been that consideration of the interface of habitat and harvest management can generate important insights into the objectives underlying the decision context. Often the objectives are very complex and trade-off against one another. The third lesson follows from the second – if an understanding of the fundamental objectives is paramount, there is no escaping the need for a better understanding of human dimensions, specifically the desires of hunters and nonhunters and the role they play in conservation. In the end, the compelling question is

Sediment and Runoff Losses following Harvesting/Site Prep Operations on a Piedmont Soil in Alabama

Treesearch

Johnny M. III Grace; Emily A. Carter

2001-01-01

Impacts of soil erosion on water quality from forest harvesting and site preparation have received increased concern in recent years. The study presented here was performed in Lee County, Alabama to investigate the impact of harvesting and site preparation on a 20-year-old loblolly pine (Pinus taeda L.) plantation on sediment and runoff yield....

Life-cycle analysis on biodiesel production from microalgae: water footprint and nutrients balance.

PubMed

Yang, Jia; Xu, Ming; Zhang, Xuezhi; Hu, Qiang; Sommerfeld, Milton; Chen, Yongsheng

2011-01-01

This research examines the life-cycle water and nutrients usage of microalgae-based biodiesel production. The influence of water types, operation with and without recycling, algal species, geographic distributions are analyzed. The results confirm the competitiveness of microalgae-based biofuels and highlight the necessity of recycling harvested water and using sea/wastewater as water source. To generate 1 kg biodiesel, 3726 kg water, 0.33 kg nitrogen, and 0.71 kg phosphate are required if freshwater used without recycling. Recycling harvest water reduces the water and nutrients usage by 84% and 55%. Using sea/wastewater decreases 90% water requirement and eliminates the need of all the nutrients except phosphate. The variation in microalgae species and geographic distribution are analyzed to reflect microalgae biofuel development in the US. The impacts of current federal and state renewable energy programs are also discussed to suggest suitable microalgae biofuel implementation pathways and identify potential bottlenecks. Copyright © 2010 Elsevier Ltd. All rights reserved.

Energy harvesting via thermo-piezoelectric transduction within a heated capillary

NASA Astrophysics Data System (ADS)

Monroe, J. G.; Bhandari, M.; Fairley, J.; Myers, O. J.; Shamsaei, N.; Thompson, S. M.

2017-07-01

Thermal-to-kinetic-to-electrical energy conversion is demonstrated through the use of a piezoelectric transducer (PZT) integrated within a section of an oscillating heat pipe (OHP) partially filled with water. The sealed PZT transducer was configured as a bow spring parallel to the dominant flow direction within the OHP. The bottom portion of the OHP was heated in increments of 50 W, while its top portion was actively cooled via water blocks. At ˜50 W, the internal fluid started to oscillate at ˜2-4 Hz due to the non-uniform vapor pressure generated in the OHP evaporator. Low-frequency fluid "pulses" were observed to occur across the flexed, in-line piezoelectric transducer, resulting in its deflection and measureable voltage spikes ranging between 24 and 63 mV. The OHP, while having its internal fluid enthalpy harvested, was found to still have an ultra-high thermal conductivity on-the-order of 10 kW/m K; however, its maximum operating heat load decreased due to the pressure drop introduced by the PZT material. The thermo-piezoelectric harvesting concept made possible via the thermally driven fluid oscillations within an OHP provides a passive method for combined energy harvesting and thermal management that is both scalable and portable.

INFINITY harvest

NASA Image and Video Library

2012-05-07

Shania Etheridge from Benjamin E. Mays Preparatory School in New Orleans shows off the head of lettuce she harvested at the INFINITY at NASA Stennis Space Center facility May 7, 2012. The Louisiana students assisted in the first harvest of lettuce from the Controlled Environment Agriculture unit, which uses an aeroponic process that involves no soil and advance LED lighting techniques.

Feasibility of Energy Harvesting Using a Piezoelectric Tire

NASA Astrophysics Data System (ADS)

Malotte, Christopher

While the piezoelectric effect has been around for some time, it has only recently caught interest as a potential sustainable energy harvesting device. Piezoelectric energy harvesting has been developed for shoes and panels, but has yet to be integrated into a marketable bicycle tire. For this thesis, the development and feasibility of a piezoelectric tire was done. This includes the development of a circuit that incorporates piezoceramic elements, energy harvesting circuitry, and an energy storage device. A single phase circuit was designed using an ac-dc diode rectifier. An electrolytic capacitor was used as the energy storage device. A financial feasibility was also done to determine targets for manufacturing cost and sales price. These models take into account market trends for high performance tires, economies of scale, and the possibility of government subsidies. This research will help understand the potential for the marketability of a piezoelectric energy harvesting tire that can create electricity for remote use. This study found that there are many obstacles that must be addressed before a piezoelectric tire can be marketed to the general public. The power output of this device is minuscule compared to an alkaline battery. In order for this device to approach the power output of an alkaline battery the weight of the device would also become an issue. Additionally this device is very costly compared to the average bicycle tire. Lastly, this device is extreme fragile and easily broken. In order for this device to become marketable the issues of power output, cost, weight, and durability must all be successfully overcome.

Nonlinear metamaterials for electromagnetic energy harvesting (Conference Presentation)

NASA Astrophysics Data System (ADS)

Oumbe Tekam, Gabin Thibaut; Ginis, Vincent; Seetharamdoo, Divitha; Danckaert, Jan

2016-09-01

Surrounded by electromagnetic radiation coming from wireless power transfer to consumer devices such as mobile phones, computers and television, our society is facing the scientific and technological challenge to recover energy that is otherwise lost to the environment. Energy harvesting is an emerging field of research focused on this largely unsolved problem, especially in the microwave regime. Metamaterials provide a very promising platform to meet this purpose. These artificial materials are made from subwavelength building blocks, and can be designed by resonate at particular frequencies, depending on their shape, geometry, size, and orientation. In this work, we show that an efficient electromagnetic energy harvester can be design by inserting a nonlinear element directly within the metamaterial unit cell, leading to the conversion of RF input power to DC charge accumulation. The electromagnetic energy harvester operating at microwave frequencies is built from a cut-wire metasurface, which operates as a quasistatic electric dipole resonator. Using the equivalent electrical circuit, we design the parameters to tune the resonance frequency of the harvester at the desired frequency, and we compare these results with numerical simulations. Finally, we discuss the efficiency of our metamaterial energy harvesters. This work potentially offers a variety of applications, for example in the telecommunications industry to charge phones, in robotics to power microrobots, and also in medicine to advance pacemakers or health monitoring sensors.

Estimation of sport fish harvest for risk and hazard assessment of environmental contaminants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poston, T.M.; Strenge, D.L.

1989-01-01

Consumption of contaminated fish flesh can be a significant route of human exposure to hazardous chemicals. Estimation of exposure resulting from the consumption of fish requires knowledge of fish consumption and contaminant levels in the edible portion of fish. Realistic figures of sport fish harvest are needed to estimate consumption. Estimates of freshwater sport fish harvest were developed from a review of 72 articles and reports. Descriptive statistics based on fishing pressure were derived from harvest data for four distinct groups of freshwater sport fish in three water types: streams, lakes, and reservoirs. Regression equations were developed to relate harvestmore » to surface area fished where data bases were sufficiently large. Other aspects of estimating human exposure to contaminants in fish flesh that are discussed include use of bioaccumulation factors for trace metals and organic compounds. Using the bioaccumulation factor and the concentration of contaminants in water as variables in the exposure equation may also lead to less precise estimates of tissue concentration. For instance, muscle levels of contaminants may not increase proportionately with increases in water concentrations, leading to overestimation of risk. In addition, estimates of water concentration may be variable or expressed in a manner that does not truly represent biological availability of the contaminant. These factors are discussed. 45 refs., 1 fig., 7 tabs.« less

Effective flocculation of Chlorella vulgaris using chitosan with zeta potential measurement

NASA Astrophysics Data System (ADS)

Low, Y. J.; Lau, S. W.

2017-06-01

Microalgae are considered as one promising source of third-generation biofuels due to their fast growth rates, potentially higher yield rates and wide ranges of growth conditions. However, the extremely low biomass concentration in microalgae cultures presents a great challenge to the harvesting of microalgae because a large volume of water needs to be removed to obtain dry microalgal cells for the subsequent oil extraction process. In this study, the fresh water microalgae Chlorella vulgaris (C. vulgaris) was effectively harvested using both low molecular weight (MW) and high MW chitosan flocculants. The flocculation efficiency was evaluated by physical appearance, supernatant absorbance, zeta potential and solids content after centrifugal dewatering. High flocculation efficiency of 98.0-99.0% was achieved at the optimal dosage of 30-40 mg/g with formation of large microalgae flocs. This study suggests that the polymer bridging mechanism was governing the flocculation behaviour of C. vulgaris using high MW chitosan. Besides, charge patch neutralisation mechanism prevailed at low MW chitosan where lower dosage was sufficient to reach near-zero zeta potential compared with the high MW chitosan. The amount of chitosan polymer present in the culture may also affect the mechanism of flocculation.

Application of Method of Variation to Analyze and Predict Human Induced Modifications of Water Resource Systems

NASA Astrophysics Data System (ADS)

Dessu, S. B.; Melesse, A. M.; Mahadev, B.; McClain, M.

2010-12-01

Water resource systems have often used gravitational surface and subsurface flows because of their practicality in hydrological modeling and prediction. Activities such as inter/intra-basin water transfer, the use of small pumps and the construction of micro-ponds challenge the tradition of natural rivers as water resource management unit. On the contrary, precipitation is barely affected by topography and plot harvesting in wet regions can be more manageable than diverting from rivers. Therefore, it is indicative to attend to systems where precipitation drives the dynamics while the internal mechanics constitutes spectrum of human activity and decision in a network of plots. The trade-in volume and path of harvested precipitation depends on water balance, energy balance and the kinematics of supply and demand. Method of variation can be used to understand and predict the implication of local excess precipitation harvest and exchange on the natural water system. A system model was developed using the variational form of Euler-Bernoulli’s equation for the Kenyan Mara River basin. Satellite derived digital elevation models, precipitation estimates, and surface properties such as fractional impervious surface area, are used to estimate the available water resource. Four management conditions are imposed in the model: gravitational flow, open water extraction and high water use investment at upstream and downstream respectively. According to the model, the first management maintains the basin status quo while the open source management could induce externality. The high water market at the upstream in the third management offers more than 50% of the basin-wide total revenue to the upper third section of the basin thus may promote more harvesting. The open source and upstream exploitation suggest potential drop of water availability to downstream. The model exposed the latent potential of economic gradient to reconfigure the flow network along the direction where the

Protoplast Volume:Water Potential Relationship and Bound Water Fraction in Spinach Leaves 1

PubMed Central

Santakumari, Mane; Berkowitz, Gerald A.

1989-01-01

Methods used to estimate the (nonosmotic) bound water fraction (BWF) (i.e. apoplast water) of spinach (Spinacia oleracea L.) leaves were evaluated. Studies using three different methods of pressure/volume (P/V) curve construction all resulted in a similar calculation of BWF; approximately 40%. The theoretically derived BWF, and the water potential (Ψw)/relative water content relationship established from P/V curves were used to establish the relationship between protoplast (i.e. symplast) volume and Ψw. Another method of establishing the protoplast volume/Ψw relationship in spinach leaves was compared with the results from P/V curve experiments. This second technique involved the vacuum infiltration of solutions at a range of osmotic potentials into discs cut from spinach leaves. These solutions contained radioactively labeled H2O and sorbitol. This dual label infiltration technique allowed for simultaneous measurement of the total and apoplast volumes in leaf tissue; the difference yielded the protoplast volume. The dual label infiltration experiments and the P/V curve constructions both showed that below −1 megapascals, protoplast volume decreases sharply with decreasing water potential; with 50% reduction in protoplast volume occurring at −1.8 megapascals leaf water potential. PMID:16666983

Identification and assessment of potential water quality impact factors for drinking-water reservoirs.

PubMed

Gu, Qing; Deng, Jinsong; Wang, Ke; Lin, Yi; Li, Jun; Gan, Muye; Ma, Ligang; Hong, Yang

2014-06-10

Various reservoirs have been serving as the most important drinking water sources in Zhejiang Province, China, due to the uneven distribution of precipitation and severe river pollution. Unfortunately, rapid urbanization and industrialization have been continuously challenging the water quality of the drinking-water reservoirs. The identification and assessment of potential impacts is indispensable in water resource management and protection. This study investigates the drinking water reservoirs in Zhejiang Province to better understand the potential impact on water quality. Altogether seventy-three typical drinking reservoirs in Zhejiang Province encompassing various water storage levels were selected and evaluated. Using fifty-two reservoirs as training samples, the classification and regression tree (CART) method and sixteen comprehensive variables, including six sub-sets (land use, population, socio-economy, geographical features, inherent characteristics, and climate), were adopted to establish a decision-making model for identifying and assessing their potential impacts on drinking-water quality. The water quality class of the remaining twenty-one reservoirs was then predicted and tested based on the decision-making model, resulting in a water quality class attribution accuracy of 81.0%. Based on the decision rules and quantitative importance of the independent variables, industrial emissions was identified as the most important factor influencing the water quality of reservoirs; land use and human habitation also had a substantial impact on water quality. The results of this study provide insights into the factors impacting the water quality of reservoirs as well as basic information for protecting reservoir water resources.

Portable Wind Energy Harvesters for Low-Power Applications: A Survey

PubMed Central

Nabavi, Seyedfakhreddin; Zhang, Lihong

2016-01-01

Energy harvesting has become an increasingly important topic thanks to the advantages in renewability and environmental friendliness. In this paper, a comprehensive study on contemporary portable wind energy harvesters has been conducted. The electrical power generation methods of portable wind energy harvesters are surveyed in three major groups, piezoelectric-, electromagnetic-, and electrostatic-based generators. The paper also takes another view of this area by gauging the required mechanisms for trapping wind flow from ambient environment. In this regard, rotational and aeroelastic mechanisms are analyzed for the portable wind energy harvesting devices. The comparison between both mechanisms shows that the aeroelastic mechanism has promising potential in producing an energy harvester in smaller scale although how to maintain the resonator perpendicular to wind flow for collecting the maximum vibration is still a major challenge to overcome for this mechanism. Furthermore, this paper categorizes the previously published portable wind energy harvesters to macro and micro scales in terms of their physical dimensions. The power management systems are also surveyed to explore the possibility of improving energy conversion efficiency. Finally some insights and research trends are pointed out based on an overall analysis of the previously published works along the historical timeline. PMID:27438834

Spectroscopic determination of the water pair potential

NASA Astrophysics Data System (ADS)

Fellers, Raymond Scott, II

This thesis details the first experimental determination of a water pair potential via nonlinear least squares fit of high precision microwave and far-IR vibration- rotation-tunneling (VRT) data. Provided is a review of the theory of intermolecular forces, methods of determining these forces by ab initio theory, and a survey of analytical forms that are parameterized to model such forces. Also reviewed are important features of water dimer VRT spectra, in particular the characteristic tunneling splittings due to hydrogen bond rearrangements, and how these features are related to the anisotropy of the water dimer potential energy surface (PES). Comparisons are made between high level ab initio calculations of the water dimer PES and a number of well known water pair potentials. The importance of the intramolecular degrees of freedom in the parameterization of a new PES is studied through a systematic series of ab initio calculations. These results suggest that a reasonably accurate pair potential can be constructed with the constraint of rigid monomers. ÅThe computation of the VRT states of the water dimer in a fully-coupled six-dimensional Hamiltonian by the split Wigner pseudospectral (SWPS) method is presented. Discussed in detail is the performance of the code and recent improvements of the algorithm which significantly decrease the execution time over an earlier implementation. The VRT states of several potentials are calculated and compared to experiment. It is shown that none of these potentials can reproduce the water dimer tunneling splittings with quantitative accuracy. The SWPS code is embedded in a non-linear least squares fitting routine and is used to fit a potential to 22 microwave and far-IR transitions. The resulting PES, VRT- 1(R,P), is derived from the ab initio/semiempirical ASPW (Anisotropic Site Potential for Water) potential which includes multipole expansions for the electrostatic, dispersion, exchange- repulsion, and induction terms

Environmental factors during seed development and their influence on pre-harvest sprouting in wheat

NASA Technical Reports Server (NTRS)

Ciha, A. J. (Principal Investigator)

1981-01-01