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Jianguo Zhang - One of the best experts on this subject based on the ideXlab platform.
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is the taklimakan desert highway Shelterbelt sustainable to long term drip irrigation with high saline groundwater
PLOS ONE, 2016Co-Authors: Jianguo Zhang, Ying Zhao, Afeng Zhang, Tibin Zhang, Rui JiangAbstract:Freshwater resources are scarce in desert regions. Highly saline groundwater of different salinity is being used to drip irrigate the Taklimakan Desert Highway Shelterbelt with a double-branch-pipe system controlling the irrigation cycles. In this study, to evaluate the dynamics of soil moisture and salinity under the current irrigation system, soil samples were collected to a 2-m depth in the Shelterbelt planted for different years and irrigated with different groundwater salinities, and soil moisture and salinity were analyzed. The results showed that both depletion of soil moisture and increase of topsoil salinity occurred simultaneously during one irrigation cycle. Soil moisture decreased from 27.4% to 2.4% for a 15-day irrigation cycle and from 26.4% to 2.7% for a 10-day-cycle, respectively. Topsoil electrical conductivity (EC) increased from 0.64 to 3.32 dS/m and 0.70 to 3.99 dS/m for these two irrigation cycles. With increased Shelterbelt age, profiled average soil moisture (0–200 cm) reduced from 12.8% (1-year) to 7.1% (10-year); however, soil moisture in 0–20-cm increased, while topsoil salinity decreased. In addition, irrigation salinity mainly affected soil salinity in the 0–20-cm range. We conclude that water supply with the double-branch-pipe is a feasible irrigation method for the Taklimakan Desert Highway Shelterbelt, and our findings provide a model for Shelterbelt construction and sustainable management when using highly saline water for irrigation in analogous habitats.
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spatial temporal distribution of soil salt crusts under saline drip irrigation in an artificial desert highway Shelterbelt
Water, 2016Co-Authors: Jianguo Zhang, Ying Zhao, Yongdong Wang, Jiaqiang LeiAbstract:Understanding the formation and spatial-temporal distribution of soil salt crusts (SSCs) is important for the sustainable management of the artificial Shelterbelt and high-salinity groundwater utility in the Taklimakan Desert in Northwest China. The SSCs in this area were sampled, and their thickness and electrical conductivity (EC) were analyzed to examine the formation mechanism and the spatial-temporal patterns of the SSCs in the Shelterbelt, which is drip irrigated with high-salinity groundwater in the Taklimakan Desert. Results demonstrated the following: (1) Soil-moisture depletion and salt accumulation at the soil surface occurred simultaneously. The soil water and salt in the different areas around the drip irrigation emitter showed different temporal dynamics in an irrigation cycle; (2) SSCs EC increased at a logarithmic rate, and SSCs thickness increased linearly with irrigation water salinity; (3) SSCs showed evident spatial distribution around the drip irrigation emitter. The EC initially increased with increasing distance from the emitter but subsequently decreased in different directions around the emitter. The highest EC was recorded at 40 cm from the emitter; (4) Topography had a significant effect on the spatial distribution of SSCs. The EC at the upslope of the emitter was higher than that at the downslope; (5) SSCs thickness showed an initial rapid increase with Shelterbelt age, which was followed by a gradual increase. However, EC decreased with Shelterbelt age. Our findings can contribute to the Shelterbelt design, construction, utility, and sustainable management and the soil and water conservation in shifting desert regions.
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spatiotemporal distribution of soil moisture and salinity in the taklimakan desert highway Shelterbelt
Water, 2015Co-Authors: Yuan Huang, Yongdong Wang, Ying Zhao, Jianguo ZhangAbstract:Salinization and secondary salinization often appear after irrigation with saline water. The Taklimakan Desert Highway Shelterbelt has been irrigated with saline ground water for more than ten years; however, soil salinity in the Shelterbelt has not been evaluated. The objective of this study was to analyze the spatial and temporal distribution of soil moisture and salinity in the Shelterbelt system. Using a non-uniform grid method, soil samples were collected every two days during one ten-day irrigation cycle in July 2014 and one day in spring, summer, and autumn. The results indicated that soil moisture declined linearly with time during the irrigation cycle. Soil moisture was greatest in the southern and eastern sections of the study area. In contrast to soil moisture, soil electrical conductivity increased from 2 to 6 days after irrigation, and then gradually decreased from 6 to 8 days after irrigation. Soil moisture was the greatest in spring and the least in summer. In contrast, soil salinity increased from spring to autumn. Long time drip-irrigation with saline groundwater increased soil salinity slightly. The soil salt content was closely associated with soil texture. The current soil salt content did not affect plant growth, however, the soil in the Shelterbelt should be continuously monitored to prevent salinization in the future.
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research on chemical characteristics of soil salt crusts with saline groundwater drip irrigation in the tarim desert highway Shelterbelt
SpringerPlus, 2013Co-Authors: Jianguo Zhang, Jiaqiang LeiAbstract:Soil salt crusts are special layers at soil surface which are widely distributed in the Trim Desert Highway Shelterbelt under drip-irrigation with high salinity groundwater. In order to reveal annual variation of their chemical characteristics, soil salt crusts in Shelterbelt of different ages in hinterland of the Taklimakan Desert were sampled. SOM, total salt, inions and pH were analyzed. Following results were obtained. SOM of salt crusts increased with the Shelterbelt ages, but increasing trend became lower gradually. Total salt, ions, and pH of salt crusts reduced gradually with the Shelterbelt ages. Total salt of salt crusts in Shelterbelt of different ages was much higher than shifting sandy land. Ions were higher than shifting sandy land, Cl-, Na+, and SO42- increased more obvious, then Mg2+, K+, Ca2+ and HCO3-, CO32- was little and nearly had no change. pH was all alkaline, pH of salt crusts in Shelterbelt of 11 years was even lower than shifting sandy land. We can include that the quality of shallow soil (0~30 cm) in the Trim Desert Highway Shelterbelt becomes better gradually.
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optimization of the saline groundwater irrigation system along the tarim desert highway ecological Shelterbelt project in china
Ecological Engineering, 2012Co-Authors: W Han, L Cao, H Yimit, Jianguo ZhangAbstract:Abstract In order to determine the best combination of the most adaptable shrub, the irrigation frequency (IF) and irrigation amount (IA) in the Tarim Desert Highway Ecological Shelterbelt Project, we investigated the soil moisture (SM), soil electrical conductivity (EC) and Shelterbelt shrubs height (SH) where the plants were irrigated with the saline groundwater (5 g L−1) bumped from the local wells. And an orthogonal array experiment was set to test the effects of the species, IF and IA on the plants height. When the different irrigation ways were used to irrigate the Shelterbelt plants, significant differences in plant species heights, soil moisture, and salt accumulation on the surface were found. All of these findings suggested that the IF 20-day with IA 30 mm every time was the better choice in which the soil moisture was above 2%, little salt accumulated on the dune surface and the most plants’ height occurred. Our results indicated that species was the more important factor to concern than IF and IA when the IA was above 15 mm with the IF less 30-day. The shrub traits determined greatly the growth status. And Haloxylon ammodendron was the best species selected among the three main Shelterbelt shrubs, Tamarix taklamakanensis, H. ammodendron and Calligonum caput-medusae in the ecological Shelterbelt project. Multivariate orthogonal array designs provided an effective strategy to determine the optimum irrigation management of individual additive components to the Shelterbelt shrubs in the Tarim Desert Highway Ecological Shelterbelt Project.
Ken C J Van Rees - One of the best experts on this subject based on the ideXlab platform.
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Shelterbelt systems establishment in Saskatchewan, Canada: a multi-criteria fuzzy logic approach to land suitability mapping
New Forests, 2020Co-Authors: Beyhan Y Amichev, Colin P. Laroque, Kenneth W. Belcher, Murray J. Bentham, Ken C J Van ReesAbstract:There is lack of guidelines helping land managers to locate suitable areas for planting new Shelterbelt agroforestry systems on their landbases. The goal of this study was to create land suitability maps for deciduous, coniferous, and shrub Shelterbelt agroforestry systems establishment across a wide range of climatic and soil zones of Saskatchewan, Canada. Spatial Shelterbelt data and a suite of 50 predictor variables were analyzed using multivariate principal component analysis (PCA), principal component regression (PCR), fuzzy logic analysis, and GIS mapping techniques. Fifty spatial datasets were used as Shelterbelt establishment predictor variables (4 groups): 21 climate (1980–2010 normals), 13 land management, 14 soils, and 2 topographic criteria. A Shelterbelt carbon inventory spatial layer was used as the Shelterbelt establishment indicator dataset. Using PCA and PCR analyses, the overall importance (cumulative loading: positive or negative) of all predictor variables was determined and used to create Shelterbelt suitability maps by means of weighted-sum overlays in GIS. Statistically significant positive correlations between mapped Shelterbelt suitability levels and observed mean Shelterbelt carbon stocks were used to evaluate the resulting deciduous (4.86 million hectares (Mha) study area; p = 0.0033, R^2 = 0.79), coniferous (1.96 Mha; p = 0.0008, R^2 = 0.77), and shrub suitability maps (2.06 Mha; p = 0.0002, R^2 = 0.83). Additional 8.76, 7.90, and 9.77 Mha were identified as suitable for planting future deciduous, coniferous, and shrub Shelterbelt systems, respectively, mapped as above-average or high suitability land. Shelterbelt suitability mapping is a means to delineating and ranking the land across large landscapes. The approach employed in this study can benefit other afforestation and agroforestry adoption studies across Canada and the world.
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demonstration and testing of the improved Shelterbelt component in the holos model
Frontiers in Environmental Science, 2020Co-Authors: Roland Krobel, Colin P. Laroque, Beyhan Y Amichev, Ken C J Van Rees, Julius Moore, Aaron Mcpherson, Laura Poppy, Raju Y Soolanayakanahally, Tricia Ward, Fardausi AkhterAbstract:Using a participatory approach, the Shelterbelt component of Canada’s whole-farm model Holos was upgraded from an age-determined to a circumference-determined (at breast height) calculation using a multi-stem averaging approach. The model interface was developed around the idea that a Shelterbelt could have multiple rows, and a variable species composition within each row. With this, the model calculates the accumulated aboveground carbon in the standing biomass and a lookup table of modelled tree growth is used to add estimates of the belowground carbon. Going from an initial interface that asks for the current state, the model also incorporates an option of past and future Shelterbelt plantings. In order to test the model’s suitability, we measured diverse Shelterbelts (evergreen, deciduous, shrub type) in southern Saskatchewan, Canada representing commonly planted woody species. By making use of Caragana, Green Ash, Colorado Spruce, Siberian Elm, and a mixed Caragana/Green Ash tree rows, we tested how many tree circumference measurements would be required to yield a representative average. Later, these results were incorporated in the Holos model to calculate the accumulated above- and below-ground carbon in each Shelterbelt type.
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Shelterbelt removals in saskatchewan canada implications for long term carbon sequestration
Agroforestry Systems, 2020Co-Authors: Beyhan Y Amichev, Colin P. Laroque, Ken C J Van ReesAbstract:Shelterbelt agroforestry systems represent an actively managed historical agricultural resource for which farmers are the driving force, and their decisions have long-term consequences. For decades, detailed records were maintained of millions of trees and shrubs planted in Shelterbelts on agricultural fields and farmyards across the Canadian Prairies. However, no records were collected regarding Shelterbelt removals. This study quantified the length and carbon (C) stocks of all removed Shelterbelts in Saskatchewan for the 2008–2016 period, and identified Shelterbelt removal trends across five soil zones. Removals were detected using a recently developed integrated GIS and remote sensing approach, and were land-use features that were mapped as Shelterbelts in an inventory map in 2008 but were missing in the classified map in 2016. A total of 2491.2 km of Shelterbelts were removed, containing 190.7 GgC (1 Gg = 1000 Mg = 1000 tonnes). The majority of C stock removals were in shrub Shelterbelts (107.2 GgC; 1676.6 km), followed by deciduous (78.1 GgC; 719.1 km) and coniferous Shelterbelts (5.4 GgC; 95.5 km). Medium (2–3 rows) and wide (> 3 rows) Shelterbelts had higher likelihood of being completely removed, while narrow (1 row) Shelterbelts were only shortened. Removals in the < 50 m length designs were one- to three-orders of magnitude higher than any other Shelterbelt length design. Future Shelterbelt removal studies could serve to sustain the carbon sequestration effectiveness of the existing and extensive Shelterbelt network on the Canadian Prairies in the long term, and to protect an important agricultural resource that took a very long time to establish.
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above and below ground carbon sequestration in Shelterbelt trees in canada a review
Forests, 2019Co-Authors: Rafaella C Mayrinck, Colin P. Laroque, Beyhan Y Amichev, Ken C J Van ReesAbstract:Shelterbelts have been planted around the world for many reasons. Recently, due to increasing awareness of climate change risks, Shelterbelt agroforestry systems have received special attention because of the environmental services they provide, including their greenhouse gas (GHG) mitigation potential. This paper aims to discuss Shelterbelt history in Canada, and the environmental benefits they provide, focusing on carbon sequestration potential, above- and below-ground. Shelterbelt establishment in Canada dates back to more than a century ago, when their main use was protecting the soil, farm infrastructure and livestock from the elements. As minimal-and no-till systems have become more prevalent among agricultural producers, soil has been less exposed and less vulnerable to wind erosion, so the practice of planting and maintaining Shelterbelts has declined in recent decades. In addition, as farm equipment has grown in size to meet the demands of larger landowners, Shelterbelts are being removed to increase efficiency and machine maneuverability in the field. This trend of Shelterbelt removal prevents Shelterbelt’s climate change mitigation potential to be fully achieved. For example, in the last century, Shelterbelts have sequestered 4.85 Tg C in Saskatchewan. To increase our understanding of carbon sequestration by Shelterbelts, in 2013, the Government of Canada launched the Agricultural Greenhouse Gases Program (AGGP). In five years, 27 million dollars were spent supporting technologies and practices to mitigate GHG release on agricultural land, including understanding Shelterbelt carbon sequestration and to encourage planting on farms. All these topics are further explained in this paper as an attempt to inform and promote Shelterbelts as a climate change mitigation tool on agricultural lands.
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distribution of soil organic carbon in the light and heavy fractions for six Shelterbelt species and their adjacent agricultural fields in saskatchewan
Canadian Journal of Soil Science, 2017Co-Authors: Gurbir Singh Dhillon, Ken C J Van ReesAbstract:Agroforestry systems play an important role in the sequestration of carbon (C) to reduce atmospheric carbon dioxide (CO2) levels. However, the extent of long-term C sequestration will depend on physical stabilization of the sequestered C. This study determined the influence of six major Shelterbelt species on soil organic carbon (SOC) distribution in the light- and heavy-density fractions of bulk soil compared with adjacent agricultural fields. Soil samples were collected from the Shelterbelts and adjacent agricultural fields and were separated into light and heavy fractions using sodium iodide solution (NaI, density = 1.6 g cm−3) and analyzed for their organic C stocks. Both the light and heavy fractions to a 50 cm soil depth contained higher SOC stocks for the Shelterbelts (21 and 91 Mg C ha−1, respectively) compared with the adjacent agricultural fields (14 and 81 Mg C ha−1, respectively). Most SOC added at the 0–10 cm soil depth was in the form of labile light fraction (92%), whereas heavy fraction co...
Ying Zhao - One of the best experts on this subject based on the ideXlab platform.
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is the taklimakan desert highway Shelterbelt sustainable to long term drip irrigation with high saline groundwater
PLOS ONE, 2016Co-Authors: Jianguo Zhang, Ying Zhao, Afeng Zhang, Tibin Zhang, Rui JiangAbstract:Freshwater resources are scarce in desert regions. Highly saline groundwater of different salinity is being used to drip irrigate the Taklimakan Desert Highway Shelterbelt with a double-branch-pipe system controlling the irrigation cycles. In this study, to evaluate the dynamics of soil moisture and salinity under the current irrigation system, soil samples were collected to a 2-m depth in the Shelterbelt planted for different years and irrigated with different groundwater salinities, and soil moisture and salinity were analyzed. The results showed that both depletion of soil moisture and increase of topsoil salinity occurred simultaneously during one irrigation cycle. Soil moisture decreased from 27.4% to 2.4% for a 15-day irrigation cycle and from 26.4% to 2.7% for a 10-day-cycle, respectively. Topsoil electrical conductivity (EC) increased from 0.64 to 3.32 dS/m and 0.70 to 3.99 dS/m for these two irrigation cycles. With increased Shelterbelt age, profiled average soil moisture (0–200 cm) reduced from 12.8% (1-year) to 7.1% (10-year); however, soil moisture in 0–20-cm increased, while topsoil salinity decreased. In addition, irrigation salinity mainly affected soil salinity in the 0–20-cm range. We conclude that water supply with the double-branch-pipe is a feasible irrigation method for the Taklimakan Desert Highway Shelterbelt, and our findings provide a model for Shelterbelt construction and sustainable management when using highly saline water for irrigation in analogous habitats.
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spatial temporal distribution of soil salt crusts under saline drip irrigation in an artificial desert highway Shelterbelt
Water, 2016Co-Authors: Jianguo Zhang, Ying Zhao, Yongdong Wang, Jiaqiang LeiAbstract:Understanding the formation and spatial-temporal distribution of soil salt crusts (SSCs) is important for the sustainable management of the artificial Shelterbelt and high-salinity groundwater utility in the Taklimakan Desert in Northwest China. The SSCs in this area were sampled, and their thickness and electrical conductivity (EC) were analyzed to examine the formation mechanism and the spatial-temporal patterns of the SSCs in the Shelterbelt, which is drip irrigated with high-salinity groundwater in the Taklimakan Desert. Results demonstrated the following: (1) Soil-moisture depletion and salt accumulation at the soil surface occurred simultaneously. The soil water and salt in the different areas around the drip irrigation emitter showed different temporal dynamics in an irrigation cycle; (2) SSCs EC increased at a logarithmic rate, and SSCs thickness increased linearly with irrigation water salinity; (3) SSCs showed evident spatial distribution around the drip irrigation emitter. The EC initially increased with increasing distance from the emitter but subsequently decreased in different directions around the emitter. The highest EC was recorded at 40 cm from the emitter; (4) Topography had a significant effect on the spatial distribution of SSCs. The EC at the upslope of the emitter was higher than that at the downslope; (5) SSCs thickness showed an initial rapid increase with Shelterbelt age, which was followed by a gradual increase. However, EC decreased with Shelterbelt age. Our findings can contribute to the Shelterbelt design, construction, utility, and sustainable management and the soil and water conservation in shifting desert regions.
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spatiotemporal distribution of soil moisture and salinity in the taklimakan desert highway Shelterbelt
Water, 2015Co-Authors: Yuan Huang, Yongdong Wang, Ying Zhao, Jianguo ZhangAbstract:Salinization and secondary salinization often appear after irrigation with saline water. The Taklimakan Desert Highway Shelterbelt has been irrigated with saline ground water for more than ten years; however, soil salinity in the Shelterbelt has not been evaluated. The objective of this study was to analyze the spatial and temporal distribution of soil moisture and salinity in the Shelterbelt system. Using a non-uniform grid method, soil samples were collected every two days during one ten-day irrigation cycle in July 2014 and one day in spring, summer, and autumn. The results indicated that soil moisture declined linearly with time during the irrigation cycle. Soil moisture was greatest in the southern and eastern sections of the study area. In contrast to soil moisture, soil electrical conductivity increased from 2 to 6 days after irrigation, and then gradually decreased from 6 to 8 days after irrigation. Soil moisture was the greatest in spring and the least in summer. In contrast, soil salinity increased from spring to autumn. Long time drip-irrigation with saline groundwater increased soil salinity slightly. The soil salt content was closely associated with soil texture. The current soil salt content did not affect plant growth, however, the soil in the Shelterbelt should be continuously monitored to prevent salinization in the future.
Guoqing Jiang - One of the best experts on this subject based on the ideXlab platform.
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a study of Shelterbelt transpiration and cropland evapotranspiration in an irrigated area in the middle reaches of the heihe river in northwestern china
IEEE Geoscience and Remote Sensing Letters, 2015Co-Authors: Chen Qiao, Rui Sun, Lei Zhang, Liangyun Liu, Lvyuan Hao, Guoqing JiangAbstract:The transpiration from Shelterbelts and the evap- otranspiration (ET) from cropland (maize and vegetables) and orchards (apple) in an irrigated area in the middle reaches of the Heihe River, China, were estimated using a modified Penman-Monteith (P-M) formula and airborne remote sensing data. The results were compared to the shelter transpiration re- sults obtained from measurements of sup flow in tree trunks made with thermal dissipation probes and the latent heat fluxes observed by the eddy covariance technique at flux towers in croplands. The modified P-M formula was found to be an effective means to estimate not only the cropland and orchard ET but also the shelter transpiration. The seasonal variation of Shelterbelt transpiration was smaller than those of cropland and orchard ET. Estimates of ET made using the P-M formula along with the remote sensing data showed that 9.9%, 3.1%, and 87.0% of the total ET were allotted to Shelterbelts, apple orchards, and cropland, respectively. Index Terms—Evapotranspiration (ET), remote sensing, shel- terbelt, transpiration, vegetation.
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A Study of Shelterbelt Transpiration and Cropland Evapotranspiration in an Irrigated Area in the Middle Reaches of the Heihe River in Northwestern China
IEEE Geoscience and Remote Sensing Letters, 2015Co-Authors: Chen Qiao, Lei Zhang, Ziwei Xu, Guoqing JiangAbstract:The transpiration from Shelterbelts and the evapotranspiration (ET) from cropland (maize and vegetables) and orchards (apple) in an irrigated area in the middle reaches of the Heihe River, China, were estimated using a modified Penman-Monteith (P-M) formula and airborne remote sensing data. The results were compared to the shelter transpiration results obtained from measurements of sup flow in tree trunks made with thermal dissipation probes and the latent heat fluxes observed by the eddy covariance technique at flux towers in croplands. The modified P-M formula was found to be an effective means to estimate not only the cropland and orchard ET but also the shelter transpiration. The seasonal variation of Shelterbelt transpiration was smaller than those of cropland and orchard ET. Estimates of ET made using the P-M formula along with the remote sensing data showed that 9.9%, 3.1%, and 87.0% of the total ET were allotted to Shelterbelts, apple orchards, and cropland, respectively.
Shuai Fu - One of the best experts on this subject based on the ideXlab platform.
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combining sap flow measurements and modelling to assess water needs in an oasis farmland Shelterbelt of populus simonii carr in northwest china
Agricultural Water Management, 2016Co-Authors: Shuai FuAbstract:Farmland Shelterbelts provide an ecological protection screen for an oasis but exhibit high mortality in the face of water shortage. It is necessary to understand farmland Shelterbelt tree transpiration under different levels of water stress and stand ages for proper management. Sap flux measurement techniques and models are among the most useful method to detect water stress and to evaluate plant water consumption. The usefulness of both methods decreases, however, when applied to species, such as Populus simonii Carr, that have an outstanding tolerance to drought and a remarkable capacity to take up water from drying soils. Our hypothesis is that analysis using simultaneous measurements of sap flow and models in the same trees is useful for assessing the irrigation needs in farmland Shelterbelts. To test our hypothesis, we analysed the relationships between canopy transpiration, canopy conductance, relative extractable water and atmospheric factors in a farmland Shelterbelt and evaluated the effectiveness of the model. Measurements were made during one growing season. The time courses of sap flow measured and modelled on days of contrasting weather and soil water conditions were analysed to evaluate the usefulness of the method to assess the crop water needs. We calculated the daily tree water consumption from sap flow measurements and the parameterized modified Jarvis-Stewart model, and we evaluated the model’s usefulness to assess the final water needs under water stress and stand ages for farmland Shelterbelt irrigation. The transpiration decreased as the soil drought increased, and it increased as the atmospheric drought increased. The time course of the water needs showed that the occurrence of water stress in the farmland Shelterbelt trees had a large impact on their water consumption, which increased as the water stress decreased, following the equation y=1/[1+e−60.67×(REWx−0.402)]. The simultaneous use of modelling and tree structural data increased the reliability of assessing water needs from youth to maturity. A similar analysis with the water consumption values, from which stand age values were derived, showed that water needs increased with the tree age following the equation y=847−844/[1+(x/87.9)1.9]. We conclude that compared to the use of sap flow records alone, the simultaneous use of sap flow records and model values provides more detailed information to assess water needs in a farmland Shelterbelt, which has an important significance for farmland Shelterbelt protection.