ارزیابی اثر کاربری اراضی و برخی ویژگی‌های خاک بر هدایت هیدرولیکی اشباع

نوع مقاله : مقالات پژوهشی

نویسندگان

1 دانشگاه جیرفت

2 دانشگاه شهید باهنر کرمان

3 دانشگاه شهیدباهنر کرمان

چکیده

ﭘﺎراﻣﺘﺮﻫﺎی ﻫﻴﺪروﻟﻴﻜﻲ ﺑﺮای درک ﺟﺮﻳﺎن رﻃﻮﺑﺖ در ﺧﺎک ﻏﻴﺮاﺷﺒﺎع ﺑﺴﻴﺎر ﻣﻬﻢ ﻣﻲ‌ﺑﺎﺷﻨﺪ و در ﻣﺪل‌سازی ﺟرﻳﺎن رطﻮﺑﺖ، آﻻﻳﻨﺪه‌ها و عناصر غذایی در ﺧﺎک، اﺳﺘﻔﺎده میﮔﺮدﻧﺪ. مدیریت خاک و کاربری اراضی، با تأثیر بر ویژگی‌های خاک می‌توانند مستقیما خصوصیات هیدرولیکی خاک را تغییر دهند. هدف اصلی این پژوهش، ارزیابی اثر کاربری‌های مختلف اراضی بر هدایت هیدرولیکی اشباع خاک (ks) بود. این پژوهش در 100 هکتار از اراضی منطقه خضرآباد در 25 کیلومتری جنوب شهرستان جیرفت انجام گردید. به کمک نرم‌افزار Google earth و Arc GIS، منطقه به بلوک‌هایی با ابعاد 1000×1000 متر شبکه‌بندی شد. مختصات جغرافیایی مراکز هر بلوک به عنوان محل نمونه‌برداری انتخاب و (ks) توسط دستگاه نفوذسنج گلف تعیین گردید. برای انجام درون‌یابی و تهیه نقشه‌های مکانی، از روش کریجینگ استفاده شد. نتایج نشان داد که (ks) با هم‌بستگی مکانی قوی از تغییرپذیری مکانی بالایی برخوردار است که این تغییرات در کاربری باغ بیش‌ترین و در کاربری بایر کم‌ترین مقدار را در برگرفتند و دلیل این امر نوع کاربری و تکنیک مدیریتی بسته به نوع کاربری و نشان‌دهنده تأثیر کاربری اراضی بر (ks) بود. الگوی پراکنش ks با متغیر شن هم‌روند و با الگوی پراکنش رس در خلاف جهت دیده شد که همین امر، تأثیر ویژگی‌های فیزیکی خاک را بر (ks) نشان داد. با توجه به پارامترهای ارزیابی MBE (میانگین انحراف خطا)، MAE (میانگین قدر مطلق خطا) و CRM (ضریب جرم باقی‌مانده)، بهترین مدل برازش داده شده به ks، مدل گاوسی بود و ویژگی‌های خاک نظیر ks، دارای تغییرپذیری مکانی وابسته به مقیاس نمونه‌برداری بودند. به‌طور کلی مشخص گردید که کاربری‌های اراضی، بسته به نوع کاربری و تکنیک مدیریتی مورد استفاده، با تأثیر بر خصوصیات خاک، باعث تغییر در ks می‌شوند.

کلیدواژه‌ها


عنوان مقاله [English]

Evaluation the Effect of Different Land Use and Soil Characteristics on Saturated Hydraulic Conductivity

نویسندگان [English]

  • Elham Afzali Moghadam 1
  • naser boroumand 2
  • vahidreza jalali 3
  • saleh sanjari 1
1 university of jiroft
2 Shahid Bahonar University of Kerman
3 Shahid Bahonar University of Kerman
چکیده [English]

Introduction: The hydraulic parameters are very important for perception of water flow in unsaturated soil and using pollutants and nutrient flow modeling in the soil. The effect of soil management and land uses on soil parameters can directly alter soil hydraulic parameters. Because of interactive and tight relationship between soil and plant covering, studying the soil parameters and its changing during different land uses is vital. The main object of this study was evaluating the effects of different land uses on soil saturated hydraulic conductivity.
Materials and Methods: This study was performed in about 100 hectare fields of Khezrabad region in the 25 km south of the Jiroft county located in south eastern of Kerman province. The region gridded into 1000×1000 meter grids with use of Google earth and Arc GIS software, sampling places has been selected in the center of each grid. Measurement of soil saturated hydraulic conductivity done with the Guelph permeameter in the center of each grid. For the measurement of physical parameters such as bulk density, percent of sand, silt, clay in the laboratory, sampling done from 30cm depth so samples transferred to the laboratory. In this study in order to ensure the normal distribution of variables, the Kolmogorov-Smirnov test has been used with SPSS14 software. The Kriging method was used for interpolation and providing spatial maps.
Results and Discussion: Agriculture, garden and sterile lands were selected for the object of the present study. The study area includes garden, agriculture and sterile lands at the same time. The study area contains 3 classes of soil texture as: sandy, sandy-loamy and loamy-sand. The results showed that soil saturated hydraulic conductivity (ks) with strong spatial correlation had a high spatial variability. The fluctuation ranges of its values changes from 0.02 to 2325.71 cm per hour. The lowest value of ks was observed in garden land (by having the lowest value of soil bulk density) while the highest value was observed in sterile land (by having the highest value of soil bulk density). The results also showed that semi-variogram of garden, agriculture and sterile land were not the same, and it may gain from different types of agricultural operations, type of land use and various textures so that from garden land to sterile land, the soil texture becomes lighter and level of saturated hydraulic conductivity changes completely different. Several reasons maybe considered including soil different structures due to different type of agricultural operations and type of cultivation for every single land use. The change process of saturated hydraulic conductivity for garden and agricultural land was identical and for both the Gaussian model were fitted. According to the nugget effect ratio to the sill (C0/C0+C), variability of saturated hydraulic conductivity in agricultural land has a stronger spatial correlation (0.0006) and also has a higher radius of effect range (11740m) compared to garden land in which the ratio of the nugget effect ratio to sill is 0.28 and its radius of effect range is 8030 meters. the radius of effect range in sterile land had the lowest value among studied land uses, though having strong correlation, the effect range of this correlation is low and, compared to other lands, the changes process was more randomly obtained. To mention the reasons of this finding it is possible to refer to area of the sterile land, dispersion of the sampling points and long distance between pair points. The lowest spatial correlation belonged to garden land with middle spatial correlation class and the reason can be explained as due to increase of sand, decrease of clay and silt, bulk density of soil increases as well and leads to increase of coarse pores and consequently increasing saturated hydraulic conductivity of soil.
Results showed that soil saturated hydraulic conductivity (ks) with strong spatial correlation has high spatial variability and these variability consist lowest quantity in the garden lands and highest quantity in the sterile lands. The distribution pattern of Ks was seen similar to the sand and the soils bulk density, this pattern was opposite to the clay distribution pattern, this indicates the effect of soil physical parameters on saturated hydraulic conductivity.
Conclusion: According to the evaluation parameters CRM, MAE and MBA, Gaussian model is the best fitted model to soil saturated hydraulic conductivity data and soil parameters such as saturated hydraulic conductivity consist spatial variability related to sampling scale. The factors of land type and consequently type of land cultivation, lands management system, type of agricultural operations, soil particles size and bulk density of soil have the most impact on variability of Ks.

کلیدواژه‌ها [English]

  • Guelph permeameter
  • Jiroft
  • Kriging
  • Spatial variability
1- Abu-Hashim M.S.D. 2011. Impact of land-use and land-management on water infiltration capacity of soils on a catchment scale. PhD Thesis Fakultat Architektur, Bauingenieurwesen and Umweltwissenschaften der Technischen Universitat Carolo-Wilhelmina zu Braunschweig, Germany.
2- Angulo-Jaramillo R., Moreno F., Clothier B.E., Thony J.L., Vachaud G., Fernandez- Boy E., and Cayuela J.A. 1997. Seasonal variation of hydraulic properties of soils measured using a tension disk infiltrometer. Soil Science Society of America Journal. 61: 27–32.
3- Barzegar A. 2004. Advanced soil physics. Publications of Shahid Chamran University. Ahvaz.
4- Bormann H., and Klaassen K. 2008. Seasonal and land use dependent variability of soil hydraulic and soil hydrological properties of two northern German soils. Geoderma. 145: 295–302.
5- Bronson K.F., Zobeck T.M., Chua T.T., Acosta-Martinez V., Van Pelt R.S., and Booker J.D. 2004. Carbon and nitrogen pools of southern high plains cropland and grassland soils. Soil Science Society of America Journal. 68 (5): 1695–1704.
6- Cambardella C.A., Moorman T.B., Parkin T.B., Karlen D.L., Turco R.F., and Konopka A. E. 1994. Field scale variability of soil properties in Central Iowa soils. Soil Sci. Soc. Am. J. 58: 1501-1511.
7- Franzluebbers A.J., Stuedemann J.A., Schomberg H.H., and Wilkinson S.R. 2000. Soil organic C and N pools under long-term pasture management in the Southern Piedmont USA. Soil Biology and Biochemistry. 32 (4): 469–478.
8- Ghorbani Dashtaki Sh., Homaee M., and Madian M.H. 2009. Effect of land use change on spatial variability of infiltration parameters. Journal of Irrigation and drainage, 2(4):206-221.
9- Hallet P.D., Nunan N., Douglas J.T., and Young I.M. 2004. Millimeter-scale spatial variability in soil water sorptivity: scale, surface elevation and subcritical repellency effects. Soil Sci. Soc. Am. J., 68: 352- 358.
10- Kelishadi H., Mossaddeghi M.R., Hajabbasi M.A., and Ayoubi S. 2014. Near-saturated soil hydraulic properties as influenced by land use management systems in Koohrang region of central Zagros, Iran. Geoderma. 213, 426-434.
11- Klute A., and DirKsen C. 1986. Hydraulic conductivity and diffusitivity: laboratory methods. In: A. Klute (Ed.), Methods of Soil Analysis. Part 1. 2nd edition. Agron. Monogr. 9. ASA and SSSA, Madison, WI. Pp. 687-734.
12- Motaghian H.R., Karimi A., and Mohammadi J. 2007. Analysis of spatial variability of specific physical and hydraulic properties of soil on a catchment scale. Journal of water and soil(agricultural sciences and technology), 22(2):432-446.
13- Neves C.S.V.J., Feller C., Guimaraes M.F., Medina C.C., Tavares Filho J., and Fortier M. 2003. Soil bulk density of homogeneous morphological units identified by the cropping profile method in clayey oxisols in Brazil. Soil & Tillage Research. 71 (2): 109–119.
14- Nielsen, D.R., Biggar J.W., and Erh K.T. 1973. Spatial variability of field-measured soil- water properties. Hilgardia. 42 (7): 215–259.
15- Rekman J., Turski R., and paluszek J. 1998. Spatial and Temporal Variations in erodibility of loess. Soil and Tillage Res. 6(1, 2): 61-68.
16- Reynolds W.D., and Elrick D.E. 1987. Laboratory and numerical assessment of the Guelph permeameter method. Soil Sci. 144: 244-282.
17- Sepaskhah A.R., Ahmadi S.H., and Nikbakht Shahbazi A.R. 2005. Geostatistical analysis of sorptivity for a soil under tilled and no-tilled conditions. Soil and Tillage Res., 83: 237-245.
18- Wei H., Mingan Sh., Quanjiu W., and Dongli S. 2013. Effects of measurement method, scale, and landscape features on variability of saturated hydraulic conductivity. ASCE. 378-386.
19- Zeinalzadeh K., Kashkuli H.A., Naser A., Dadmehr R., and Eivazi A.R. 2009 Temporal chenges soil hydraulic parameters in agriculture different land uses. Journal of water research in agriculture(formerly soil and water sciences), 24(1):1-11.
20- Zhou X., Lin H.S., and White E.A. 2008. Surface soil hydraulic properties in four soil series under different land use and their temporal changes. Catena 73, 180–188.
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