Water harvesting and supplemental irrigation for improved water use efficiency in dry areas

Productivity / Water harvesting / Runoff / Water storage / Crop production / Water use efficiency / Arid lands / Water resources development / Rain-fed farming / Supplementary irrigation / Irrigation scheduling / Environmental effects / Research priorities / Case studies / West Asia / North Africa / India / Libya / Syria / Burkina Faso

The Temporal Efficiency of SO2 Emissions Trading

This paper provides an empirical evaluation of the temporal efficiency of the US Acid Rain Program, which implemented a nationwide market for trading and banking sulphur dioxide (SO2) emission allowances. We first develop a model of efficient banking and select appropriate parameter values. Then we use aggregate data from the first seven years of the Acid Rain Program to access the temporal efficiency of the observed banking behaviour. We find that banking has been surprisingly efficient and we discuss why this finding disagrees with the common perception of excessive banking in this program.emissions trading, banking, acid rain, tradable permits

Morphology of rain water channelization in systematically varied model sandy soils

We visualize the formation of fingered flow in dry model sandy soils under different raining conditions using a quasi-2d experimental set-up, and systematically determine the impact of soil grain diameter and surface wetting property on water channelization phenomenon. The model sandy soils we use are random closely-packed glass beads with varied diameters and surface treatments. For hydrophilic sandy soils, our experiments show that rain water infiltrates into a shallow top layer of soil and creates a horizontal water wetting front that grows downward homogeneously until instabilities occur to form fingered flows. For hydrophobic sandy soils, in contrast, we observe that rain water ponds on the top of soil surface until the hydraulic pressure is strong enough to overcome the capillary repellency of soil and create narrow water channels that penetrate the soil packing. Varying the raindrop impinging speed has little influence on water channel formation. However, varying the rain rate causes significant changes in water infiltration depth, water channel width, and water channel separation. At a fixed raining condition, we combine the effects of grain diameter and surface hydrophobicity into a single parameter and determine its influence on water infiltration depth, water channel width, and water channel separation. We also demonstrate the efficiency of several soil water improvement methods that relate to rain water channelization phenomenon, including pre-wetting sandy soils at different level before rainfall, modifying soil surface flatness, and applying superabsorbent hydrogel particles as soil modifiers

The Temporal Efficiency of SO2 Emissions Trading

This paper provides an empirical evaluation of the temporal efficiency of the U.S. Acid Rain Program, which implemented a nationwide market for trading and banking sulfur dioxide (SO2) emission allowances. We first develop a model of efficient banking and select appropriate parameter values. Then, we use aggregate data from the first seven years of the Acid Rain Program, to assess the temporal efficiency of the observed banking behavior. We find that banking has been surprisingly efficient and we discuss why this finding disagrees with the common perception of excessive banking in this program.

The temporal efficiency of SO₂ emissions trading

This paper provides an empirical evaluation of the temporal efficiency of the U.S. Acid Rain Program, which implemented a nationwide market for trading and banking sulfur dioxide (SO2) emission allowances. We first develop a model of efficient banking and select appropriate parameter values. Then, we use aggregate data from the first seven years of the Acid Rain Program, to assess the temporal efficiency of the observed banking behavior. We find that banking has been surprisingly efficient and we discuss why this finding disagrees with the common perception of excessive banking in this program

Net ecosystem carbon exchange in three contrasting Mediterranean ecosystems ? the effect of drought

International audienceDroughts reduce gross primary production (GPP) and ecosystem respiration (Reco), contributing to most of the inter-annual variability in terrestrial carbon sequestration. In seasonally dry climates (Mediterranean), droughts result from reductions in annual rainfall and changes in rain seasonality. We compared carbon fluxes measured by the eddy covariance technique in three contrasting ecosystems in southern Portugal: an evergreen oak woodland (savannah-like) with ca.~21% tree crown cover, a grassland dominated by herbaceous annuals and a coppiced short-rotation eucalyptus plantation. During the experimental period (2003?2006) the eucalyptus plantation was always the strongest sink for carbon: net ecosystem exchange rate (NEE) between ?861 and ?399 g C m?2 year?1. The oak woodland and the grassland were much weaker sinks for carbon: NEE varied in the oak woodland between ?140 and ?28 g C m?2 year?1 and in the grassland between ?190 and +49 g C m?2 year?1. The eucalyptus stand had higher GPP and a lower proportion of GPP spent in respiration than the other systems. The higher GPP resulted from high leaf area duration (LAD), as a surrogate for the photosynthetic photon flux density absorbed by the canopy. The eucalyptus had also higher rain use efficiency (GPP per unit of rain volume) and light use efficiency (the daily GPP per unit incident photosynthetic photon flux density) than the other two ecosystems. The effects of a severe drought could be evaluated during the hydrological-year (i.e., from October to September) of 2004?2005. Between October 2004 and June 2005 the precipitation was only 40% of the long-term average. In 2004?2005 all ecosystems had GPP lower than in wetter years and carbon sequestration was strongly restricted (less negative NEE). The grassland was a net source of carbon dioxide (+49 g C m?2 year?1). In the oak woodland a large proportion of GPP resulted from carbon assimilated by its annual vegetation component, which was strongly affected by the shortage of rain in winter. Overall, severe drought affected more GPP than Reco leading to the deterioration of NEE. Although the rain-use efficiency of the eucalyptus plantation increased in the dry year, this was not the case of evergreen oak woodland, which rain-use efficiency was not influenced by drought. Recovery after drought alleviation, i.e., beginning with heavy rain in October 2005, was fully accomplished in 2006 in the oak woodland and grassland, but slow in the eucalyptus plantation

Rain water transport and storage in a model sandy soil with hydrogel particle additives

We study rain water infiltration and drainage in a dry model sandy soil with superabsorbent hydrogel particle additives by measuring the mass of retained water for non-ponding rainfall using a self-built 3D laboratory set-up. In the pure model sandy soil, the retained water curve measurements indicate that instead of a stable horizontal wetting front that grows downward uniformly, a narrow fingered flow forms under the top layer of water-saturated soil. This rain water channelization phenomenon not only further reduces the available rain water in the plant root zone, but also affects the efficiency of soil additives, such as superabsorbent hydrogel particles. Our studies show that the shape of the retained water curve for a soil packing with hydrogel particle additives strongly depends on the location and the concentration of the hydrogel particles in the model sandy soil. By carefully choosing the particle size and distribution methods, we may use the swollen hydrogel particles to modify the soil pore structure, to clog or extend the water channels in sandy soils, or to build water reservoirs in the plant root zone

Water scarcity and managing seasonal water crisis: lessons from the Kirindi Oya Project in Sri Lanka

Irrigation management / Water management / Irrigation programs / Irrigated farming / Rain / Crop production / Crop yield / Rice / Case studies / River basins / Catchment areas / Irrigation scheduling / Water allocation / Water use efficiency / Water scarcity / Water shortage / Water demand / Reservoirs / Flow / Farmer participation / Farmer-agency interactions / Farmers' associations / Seasonal variation / Water distribution / Sri Lanka / Kirindi Oya / Ellegala / Lunugamwehera Reservoir

Pemakaian Bahan Bakar Gas Menjadi Alternatif Bagi Kendaraan Bermotor Berbahan Bakar Premium

Indartono, in paper use of alternative fuel gas for a motor vehicle fuel oil explain that in many ways energy efficiency can also be more than just preservation. Energy efficiency is an attempt to reduce the use of petroleum materials and the selection of alternative fuels. Improved energy efficiency is also an environmental demands, because it can reduce air pollution, acid rain control the incidence and protect the earth from global warming, which may occur due to buildup of carbon dioxide in the atmosphere. One of the alternative fuel is CNG. In motor vehicles, CNG USAge advantages include lower price, the exhaust gas is cleaner burning results and the potential source is still very large

From Sensing to Action: Quick and Reliable Access to Information in Cities Vulnerable to Heavy Rain

Cities need to constantly monitor weather to anticipate heavy storm events and reduce the impact of floods. Information describing precipitation and ground conditions at high spatio-temporal resolution is essential for taking timely action and preventing damages. Traditionally, rain gauges and weather radars are used to monitor rain events, but these sources provide low spatial resolutions and are subject to inaccuracy. Therefore, information needs to be complemented with data from other sources: from citizens' phone calls to the authorities, to relevant online media posts, which have the potential of providing timely and valuable information on weather conditions in the city. This information is often scattered through different, static, and not-publicly available databases. This makes it impossible to use it in an aggregate, standard way, and therefore hampers efficiency of emergency response. In this paper, we describe information sources relating to a heavy rain event in Rotterdam on October 12-14, 2013. Rotterdam weather monitoring infrastructure is composed of a number of rain gauges installed at different locations in the city, as well as a weather radar network. This sensing network is currently scarcely integrated and logged data are not easily accessible during an emergency. Therefore, we propose a reliable, efficient, and low-cost ICT infrastructure that takes information from all relevant sources, including sensors as well as social and user contributed information and integrates them into a unique, cloud-based interface. The proposed infrastructure will improve efficiency in emergency responses to extreme weather events and, ultimately, guarantee more safety to the urban population