Assessing water footprint of wheat production in China using a crop-model-coupled-statistics approach

Abstract. The aim of this study is to estimate the green and blue water footprint of wheat, distinguishing the irrigated and rain-fed crop, from a production perspective. The assessment herein focuses on China and improves upon earlier research by taking a crop-model-coupled-statistics approach to estimate the water footprint of the crop in 30 provinces. We have calculated the water footprint at regional scale based on the actual data collected from 442 typical irrigation districts. Crop evapotranspiration and the water conveyance loss are both considered in calculating irrigated water footprint at the regional scale. We have also compared water footprint of per unit product between irrigated and rain-fed crops and analyzed the relationship between promoting yield and saving water resources. The national wheat production in the year 2010 takes about 142.5 billion cubic meters of water. The major portion of WF (80.9%) comes from the irrigated farmland and the remaining 19.1% falls into the rain-fed. Green water (50.3%) and blue water (49.7%) carry almost equal shares of water footprint (WF) in total cropland WF. Green water dominates the south of the Yangtze River, whereas low green water proportions relate themselves to the provinces located in the north China especially northwest China. Approximately 38.5% of the water footprint related to the production of wheat is not consumed in the form of crop evapotranspiration but of conveyance loss during irrigation process. Proportions of blue water for conveyance loss (BWCL) in the arid Xinjiang, Ningxia and Neimenggu (Inner Mongolia) exceed 40% due to low irrigation efficiency. The national average water footprint of wheat per unit of crop (WFP) is 1.237 m3 kg−1 in 2010. There exists a big difference in WFP among provinces. Compared to the rain-fed cultivation (with no irrigation), irrigation has promoted crop yield, both provincially and up by about 170% nationally. As a result, more water resources are demanded in irrigated farmland for per kg of wheat production. WFP for irrigated (WFPI) and rain-fed (WFPR) crops are 1.246 and 1.202 m3 kg−1 respectively. We have divided the 30 provinces into three categories according to the relation between WFPI and WFPR: (I) WFPI < WFPR, (II) WFPI is equivalent to WFPR, and (III) WFPI > WFPR. Category II, which contains major wheat producing areas in the North China Plain, contribute nearly 75% of wheat production to the country. Provinces belonging to Category III have to invest 0.478 cubic meters of water in order to harvest 1 kg wheat product. Double benefits of saving water and promoting production can be achieved substantially by irrigating wheat in Category I provinces. Nevertheless, provinces in this category, which should have contributed more, are summed to produce only 1.1% of the national wheat production.

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An improved method for calculating the regional crop water footprint based on a hydrological process analysis

Hydrology and Earth System Sciences ◽

10.5194/hess-22-5111-2018 ◽

2018 ◽

Vol 22 (10) ◽

pp. 5111-5123 ◽

Cited By ~ 3

Author(s):

Xiao-Bo Luan ◽

Ya-Li Yin ◽

Pu-Te Wu ◽

Shi-Kun Sun ◽

Yu-Bao Wang ◽

...

Keyword(s):

Water Resources ◽

Water Use ◽

Water Footprint ◽

Process Analysis ◽

Regional Scale ◽

Irrigation District ◽

Green Water ◽

Hydrological Process ◽

Total Water ◽

Crop Water

Abstract. Fresh water is consumed during agricultural production. With the shortage of water resources, assessing the water use efficiency is crucial to effectively manage agricultural water resources. The water footprint is an improved index for water use evaluation, and it can reflect the quantity and types of water usage during crop growth. This study aims to establish a method for calculating the regional-scale water footprint of crop production based on hydrological processes, and the water footprint is quantified in terms of blue and green water. This method analyses the water-use process during the growth of crops, which includes irrigation, precipitation, groundwater, evapotranspiration, and drainage, and it ensures a more credible evaluation of water use. As illustrated by the case of the Hetao irrigation district (HID), China, the water footprint of wheat, corn and sunflowers were calculated using this method. The results show that canal water loss and evapotranspiration were responsible for most of the water consumption and accounted for 47.9 % and 41.8 % of the total consumption, respectively. The total water footprint of wheat, corn and sunflowers were 1380–2888, 942–1774 and 2095–4855 m3 t−1, respectively, and the blue footprint accounts for more than 86 %. The spatial distribution pattern of the green, blue and total water footprints for the three crops demonstrated that higher values occurred in the eastern part of the HID, which had more precipitation and was further away from the irrigation gate. This study offers a vital reference for improving the method used to calculate the crop water footprint.

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Water footprint in family farming

Research Society and Development ◽

10.33448/rsd-v10i6.15777 ◽

2021 ◽

Vol 10 (6) ◽

pp. e26610615777

Author(s):

Ana Luiza Grateki Barbosa ◽

Daniel Brasil Ferreira Pinto ◽

Rafael Alvarenga Almeida

Keyword(s):

Water Resources ◽

Fresh Water ◽

Agricultural Production ◽

Water Footprint ◽

Green Water ◽

Blue Water ◽

Total Water ◽

Family Farming ◽

Gray Water ◽

The Family

Currently, the management of water resources has gained greater visibility and has become indispensable, with the need for different methodologies which consider all water used and incorporated in the processes and products. In this way, the water footprint concept has been introduced to calculate the appropriation of fresh water on the part of the humankind. Thus, the objective of this work was to determine the water footprint in some sectors of family farming in the municipality of Teófilo Otoni – MG, analyzing the agricultural production of crops cultivated exclusively by the sector in 2017 in Teófilo Otoni. The cultivation of pumpkin, banana, chayote, beans, cassava, Maize, peppers, okra, cabbage, and tangerine were studied. Thus, the total water footprint for the year 2017 was 13,996,735.05 m3.t-1, in which the green water footprint represents 86%, the blue water footprint represents 12.5% and the gray water footprint equals 1.5%. The family farming sector of Teófilo Otoni demands an average of 196.73 liters for a production of R$ 1.00.

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Regional assessment of green and blue water consumption for tomato cultivated in Southern Italy

The Journal of Agricultural Science ◽

10.1017/s0021859617000831 ◽

2017 ◽

Vol 156 (5) ◽

pp. 689-701 ◽

Cited By ~ 1

Author(s):

D. Ventrella ◽

L. Giglio ◽

P. Garofalo ◽

A. Dalla Marta

Keyword(s):

Water Policy ◽

Southern Italy ◽

Water Footprint ◽

Regional Scale ◽

Green Water ◽

Blue Water ◽

Future Scenarios ◽

Evaporative Demand ◽

Scarce Water ◽

Higher Temperature

AbstractIn the current regional-scale study, the model DSSAT CROPGRO was applied in order to simulate the cultivation of industrial tomato and to estimate the green water (GW), blue water (BW), blue water requirement (BWR) and water footprint (WFP) through a dual-step approach (with and without full irrigation). Simulation covered a period of 30 years for three climate scenarios including a reference period and two future scenarios based on forecast global average temperature increases of 2 and 5 °C. The spatial patterns of indicators relating to the whole territory of Puglia region (Southern Italy), characterized by the high evaporative demand of the atmosphere, are discussed and analysed. Considering the climatic pattern, the analysis was developed for three areas (Northern, Central and Southern). Future scenarios affected all indicators significantly, particularly the Northern area, characterized by higher temperature and rainfall anomalies. Under the A5 scenario, compared with the baseline, this area was forecast to have a large increase of BW (+30%) and reduction in yield (−20%). As a consequence, the BWR and WFP were predicted to increase dramatically, up to 40 and >65%, respectively. On the other hand, Central and Southern areas, with lower anomalies of temperature and rainfall, were forecast to be less vulnerable to climate change. The distributed analysis performed could be important for water policy, allowing most efficient allocation of scarce water resources and concentrating them where the WFP is lowest, or in other words, water use efficiency is highest.

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Changes in the water footprint of urban green spaces over time

10.5194/egusphere-egu21-100 ◽

2021 ◽

Author(s):

Hamideh Nouri ◽

Sattar Chavoshi Borujeni ◽

Pamela Nagler ◽

Armando Barreto Munoz ◽

Kamel Didan ◽

...

Keyword(s):

Water Resources ◽

Green Space ◽

Water Footprint ◽

Green Spaces ◽

Green Water ◽

Blue Water ◽

Urban Green ◽

Urban Green Spaces ◽

Urban Greenery ◽

Green And Blue Water

<p>The concept of a sustainable green city based on Sustainable Development Goals (SDGs)&#8211;Goal 11 - sustainable cities and communities &#8211; may not be narrowed down to solely intensifying urban green spaces. Sustainability could include urban water management to alleviate possible conflict among &#8220;water&#8208;saving&#8221; and &#8220;greening cities&#8221; strategies. Water consumption by urban greenery has a major role in urban water management, particularly in water-scarce regions where green covers are most affected by drought and aridity. More green and blue water resources are required to maintain and expand urban green spaces. Quantifying the water footprint of urban greenery helps to balance greening cities while water saving from both green and blue water resources. We employed remote sensing and artificial intelligence techniques to assess the water consumption and water footprint of a 780&#8208;ha public green space, the Adelaide Parklands in Australia. We estimated the green and blue water footprint of this green space (containing 29 parks) during 2010-2018 on a monthly basis. Our results showed that the mean total water footprint of the Adelaide Parklands was about 7.75 gigaliter per annum over 2010-2018; it varied from 7.19 gigaliter/year in 2018 to 8.45 gigaliter/year in 2012. The blue water footprint was consistently higher than the green water footprint even in wet time of the year. We suggest implementing sponge city and water sensitive urban design (WSUD) techniques to help greening cities while reducing the water footprint of urban green spaces. These approaches have the potential to lessen the pressure on blue water resources and optimise the consumption of green water resources.</p>

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Assessing blue and green water utilisation in wheat production of China from the perspectives of water footprint and total water use

Hydrology and Earth System Sciences ◽

10.5194/hess-18-3165-2014 ◽

2014 ◽

Vol 18 (8) ◽

pp. 3165-3178 ◽

Cited By ~ 35

Author(s):

X. C. Cao ◽

P. T. Wu ◽

Y. B. Wang ◽

X. N. Zhao

Keyword(s):

Water Use ◽

Yangtze River ◽

Water Footprint ◽

Wheat Yield ◽

Green Water ◽

Blue Water ◽

Total Water ◽

Wheat Production ◽

The Relationship ◽

Wheat Product

Abstract. The aim of this study is to estimate the green and blue water footprint (WF) and the total water use (TWU) of wheat crop in China in both irrigated and rainfed productions. Crop evapotranspiration and water evaporation loss are both considered when calculating the water footprint in irrigated fields. We compared the water use for per-unit product between irrigated and rainfed crops and analyzed the relationship between promoting the yield and conserving water resources. The national total and per-unit-product WF of wheat production in 2010 were approximately 111.5 Gm3 (64.2% green and 35.8% blue) and 0.968 m3 kg−1, respectively. There is a large difference in the water footprint of the per-kilogram wheat product (WFP) among different provinces: the WFP is low in the provinces in and around the Huang–Huai–Hai Plain, while it is relatively high in the provinces south of the Yangtze River and in northwestern China. The major portion of WF (80.9%) comes from irrigated farmland, and the remaining 19.1% is rainfed. Green water dominates the area south of the Yangtze River, whereas low green water proportions are found in the provinces located in northern China, especially northwestern China. The national TWU and total water use of the per-kilogram wheat product (TWUP) are 142.5 Gm3 and 1.237 m3 kg−1, respectively, containing approximately 21.7% blue water percolation (BWp). The values of WFP for irrigated (WFPI) and rainfed (WFPR) crops are 0.911 and 1.202 m3 kg−1, respectively. Irrigation plays an important role in food production, promoting the wheat yield by 170% and reducing the WFP by 24% compared to those of rainfed wheat production. Due to the low irrigation efficiency, more water is needed per kilogram in irrigated farmland in many arid regions, such as the Xinjiang, Ningxia and Gansu Provinces. We divided the 30 provinces of China into three categories according to the relationship between the TWUPI (TWU for per-unit product in irrigated farmland) and TWUPR (TWU for per-unit product in rainfed farmland): (I) TWUPI < TWUPR, (II) TWUPI = TWUPR, and (III) TWUPI > TWUPR. Category II, which contains the major wheat-producing areas in the North China Plain, produces nearly 75% of the wheat of China. The double benefits of conserving water and promoting production can be achieved by irrigating wheat in Category I provinces. Nevertheless, the provinces in this category produce only 1.1% of the national wheat yield.

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A site-specific agricultural water requirement and footprint estimator (SPARE:WATER 1.0) for irrigation agriculture

Geoscientific Model Development Discussions ◽

10.5194/gmdd-6-645-2013 ◽

2013 ◽

Vol 6 (1) ◽

pp. 645-684 ◽

Cited By ~ 2

Author(s):

S. Multsch ◽

Y. A. Al-Rumaikhani ◽

H.-G. Frede ◽

L. Breuer

Keyword(s):

Water Footprint ◽

Regional Scale ◽

Water Requirement ◽

Green Water ◽

Blue Water ◽

Agricultural Water ◽

Grey Water ◽

Continental Scale ◽

Irrigation Methods ◽

Irrigation Agriculture

Abstract. The water footprint accounting method addresses the quantification of water consumption in agriculture, whereby three types of water to grow crops are considered, namely green water (consumed rainfall), blue water (irrigation from surface or groundwater) and grey water (water needed to dilute pollutants). Most of current water footprint assessments focus on global to continental scale. We therefore developed the spatial decision support system SPARE:WATER that allows to quantify green, blue and grey water footprints on regional scale. SPARE:WATER is programmed in VB.NET, with geographic information system functionality implemented by the MapWinGIS library. Water requirement and water footprints are assessed on a grid-basis and can then be aggregated for spatial entities such as political boundaries, catchments or irrigation districts. We assume in-efficient irrigation methods rather than optimal conditions to account for irrigation methods with efficiencies other than 100%. Furthermore, grey water can be defined as the water to leach out salt from the rooting zone in order to maintain soil quality, an important management task in irrigation agriculture. Apart from a thorough representation of the modelling concept we provide a proof of concept where we assess the agricultural water footprint of Saudi Arabia. The entire water footprint is 17.0 km3 yr−1 for 2008 with a blue water dominance of 86%. Using SPARE:WATER we are able to delineate regional hot spots as well as crop types with large water footprints, e.g. sesame or dates. Results differ from previous studies of national-scale resolution, underlining the need for regional water footprint assessments.

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Water Footprint

Oxford Research Encyclopedia of Environmental Science ◽

10.1093/acrefore/9780199389414.013.382 ◽

2017 ◽

Author(s):

Maite M. Aldaya ◽

M. Ramón Llamas ◽

Arjen Y. Hoekstra

Keyword(s):

Water Management ◽

Supply Chain ◽

Life Cycle ◽

Water Resources ◽

Supply Chains ◽

Water Use ◽

Water Consumption ◽

Water Footprint ◽

Green Water ◽

Blue Water

This is an advance summary of a forthcoming article in the Oxford Research Encyclopedia of Environmental Science. Please check back later for the full article. The water footprint concept broadens the scope of traditional national and corporate water accounting as it has been previously known. It highlights the ways in which water consuming and polluting activities relate to the structure of the global economy, opening a window of opportunity to increase transparency and improve water management along whole-production and supply chains. This concept adds a new dimension to integrated water resources management in a globalized world. The water footprint is a relatively recent indicator. Created in 2002, it aims to quantify the effect of consumption and trade on the use of water resources. Specifically, the water footprint is an indicator of freshwater use that considers both direct and indirect water use of a consumer or producer. For instance, the water footprint of a product refers to the volume of freshwater used to produce the product, tracing the origin of raw material and ingredients along their respective supply chains. This novel indirect component of water use in supply chains is, in many cases, the greatest share of water use, for example, in the food and beverage sector and the apparel industry. Water footprint assessment shows the full water balance, with water consumption and pollution components specified geographically and temporally and with water consumption specified by type of source (e.g., rainwater, groundwater, or surface water). It introduces three components: 1. The blue water footprint refers to the consumption of blue water resources (i.e., surface and groundwater including natural freshwater lakes, manmade reservoirs, rivers, and aquifers) along the supply chain of a product, versus the traditional and restricted water withdrawal measure. 2. The green water footprint refers to consumption through transpiration or evaporation of green water resources (i.e., soilwater originating from rainwater). Green water maintains natural vegetation (e.g., forests, meadows, scrubland, tundra) and rain-fed agriculture, yet plays an important role in most irrigated agriculture as well. Importantly, this kind of water is not quantified in most traditional agricultural water use analyses. 3. The grey water footprint refers to pollution and is defined as the volume of freshwater that is required to assimilate the load of pollutants given natural concentrations for naturally occurring substances and existing ambient water-quality standards. The water footprint concept has been incorporated into public policies and international standards. In 2011, the Water Footprint Network adopted the Water Footprint Assessment Manual, which provides a standardized method and guidelines. In 2014, the International Organization for Standardization adopted a life cycle-based ISO 14046 standard for the water footprint; it offers guidelines to integrate water footprint analysis in life-cycle assessment for products. In practice, water footprint assessment generally results in increased awareness of critical elements in a supply chain, such as hotspots that deserve most attention, and what can be done to improve water management in those hotspots. Water footprint assessment, including the estimation of virtual water trade, applied in different countries and contexts, is producing new data and bringing larger perspectives that, in many cases, lead to a better understanding of the drivers behind water scarcity.

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A Site-sPecific Agricultural water Requirement and footprint Estimator (SPARE:WATER 1.0)

Geoscientific Model Development ◽

10.5194/gmd-6-1043-2013 ◽

2013 ◽

Vol 6 (4) ◽

pp. 1043-1059 ◽

Cited By ~ 12

Author(s):

S. Multsch ◽

Y. A. Al-Rumaikhani ◽

H.-G. Frede ◽

L. Breuer

Keyword(s):

Agricultural Sector ◽

Water Footprint ◽

Regional Scale ◽

Green Water ◽

Blue Water ◽

Agricultural Water ◽

Crop Water ◽

Grey Water ◽

Site Specific ◽

Irrigation Methods

Abstract. The agricultural water footprint addresses the quantification of water consumption in agriculture, whereby three types of water to grow crops are considered, namely green water (consumed rainfall), blue water (irrigation from surface or groundwater) and grey water (water needed to dilute pollutants). By considering site-specific properties when calculating the crop water footprint, this methodology can be used to support decision making in the agricultural sector on local to regional scale. We therefore developed the spatial decision support system SPARE:WATER that allows us to quantify green, blue and grey water footprints on regional scale. SPARE:WATER is programmed in VB.NET, with geographic information system functionality implemented by the MapWinGIS library. Water requirements and water footprints are assessed on a grid basis and can then be aggregated for spatial entities such as political boundaries, catchments or irrigation districts. We assume inefficient irrigation methods rather than optimal conditions to account for irrigation methods with efficiencies other than 100%. Furthermore, grey water is defined as the water needed to leach out salt from the rooting zone in order to maintain soil quality, an important management task in irrigation agriculture. Apart from a thorough representation of the modelling concept, we provide a proof of concept where we assess the agricultural water footprint of Saudi Arabia. The entire water footprint is 17.0 km3 yr−1 for 2008, with a blue water dominance of 86%. Using SPARE:WATER we are able to delineate regional hot spots as well as crop types with large water footprints, e.g. sesame or dates. Results differ from previous studies of national-scale resolution, underlining the need for regional estimation of crop water footprints.

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Spatial Characteristics and Implications of Grey Water Footprint of Major Food Crops in China

Water ◽

10.3390/w11020220 ◽

2019 ◽

Vol 11 (2) ◽

pp. 220 ◽

Cited By ~ 1

Author(s):

Lin Wang ◽

Yutong Zhang ◽

Ling Jia ◽

Guiyu Yang ◽

Yizhen Yao ◽

...

Keyword(s):

Water Resources ◽

Water Footprint ◽

Water Environment ◽

Sustainable Use ◽

Northwest China ◽

Application Rate ◽

Green Water ◽

Blue Water ◽

Grey Water ◽

Fertilizer Application Rate

The estimated, effective increase of agricultural fertilizer applied in China by 10.57 Mts from 2006 to 2016 is a crucial factor affecting the water environment. Based on analyzing the nitrate-leaching rate, the nitrogen-fertilizer application rate, and crop yield in wheat and maize key cultivation divisions in China, this paper applied the grey water footprint analytical method to estimate THE grey water footprint and its proportion to total water footprint and analyzed the spatial differences from 2012 to 2016. Results showed that the grey water footprint of wheat was higher in North and Northwest China with an increasing trend, while that of maize was higher in Southwest and Northwest China because of high nitrogen application rates and low yields in these regions. Except for the Southwestern division, wheat’s grey water footprint was about 1.3 times higher than the blue water footprint, while, for maize, it was two to three times higher. When analyzing and planning water demand for crop irrigation, the water required for nonpoint source pollution due to chemical fertilizers should be considered. Focusing blue water (irrigation) alone, while neglecting green water and ignoring grey water footprints, it might lead to overestimation of available agricultural water resources and failure to meet the goals of sustainable use of water resources.

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