• 제목/요약/키워드: Semi-arid Region

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Climate Change Impacts in Natural Resources and Livestock in Mongolia Climate

  • Batima, P.;Natsagdorj, L.;Bayarbaatar, L..;Bolortsetseg, B.;Natsagsuren, N.;Erdenetsetseg, B.
    • 한국제4기학회지
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    • 제18권2호통권23호
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    • pp.103-104
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    • 2004
  • This paper discuss some results of observed changes of meteorological elements as temperature, precipitation and some extreme indexes in Mongolia. Mongolia is one of the largest landlocked countries in the world. The climate is characterized by a long lasting cold winter, dry and hot summer, low precipitation, high temperature fluctuation and relatively high number of sunny days per year. During last 60 years the annual mean air temperature has risen $1.66^{\circ}C$. Intensive warming of > $2^{\circ}C$ was observed at higher altitudes of high mountains when warming of < $1^{\circ}C$ was observed the Domod steppe and the Gobi Desert. Heat Wave Duration have statistically significant risen trend with increaded number of days by 8-18 at significance level of 95-99.9% depending on geography and Cold Wave Duration have shortened by 13.3 days significance level of 95-99%. In general, by the amount of precipitation, Mongolia falls in semi-arid and arid region. It is 300-350 mm in the high mountain regions while it is only 50-150 mm in Gobi Desert regions. The changes of annual precipitation have very localized character i.e.decreasing at one site and increasing at a sit nearby. Annual precipitation decreased by 30-90 mm in the northern-central region and increased by 2-60 mm in the western and eastern region. The magnitude of alteration changes in precipitation regardless increasing or decreasing is 5-25%. A trends, significant at the level of 90%, found where changes are more than 40 mm or more than 15% of annual mean value. Moreover, the soil moisture resources was decreased in the last 40 years. Specially, moisture contents of the top soil have decreased 2 times(N. Natsagsuren, 2002). Months of June and July in Mongolia is the year that moisture is not inhibiting vegetation growth. Unfortunately, its also found that moisture in this time tends to decrease. Increased temperature, decreased precipitation and soil moisture are most likely resulted in occurences of more intense drought spells that have taken place during the recent years. Intimately, these changes have considerable impact on livestock in Mongolia.

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Effects of dexamethasone on progesterone and estrogen profiles and uterine progesterone receptor localization during pregnancy in Sahel goat in Semi-Arid region

  • Yahi, Dauda;Ojo, Nicholas Adetayo;Mshelia, Gideon Dauda
    • Journal of Animal Science and Technology
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    • 제59권5호
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    • pp.12.1-12.7
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    • 2017
  • Background: Despite the widespread use of dexamethasone in veterinary and human medicine, it is reported to cause some severe pregnancy related side effects like abortion in some animals. The mechanism of the response is not clear but seems to be related to interspecies and/or breed difference in response which may involve alterations in the concentrations of some reproductive hormones. Methods: Twenty Sahel goats comprising 18 does and 2 bucks were used for this study. Pregnancies were achieved by natural mating after synchronization. Repeated dexamethasone injections were given at 0.25 mg/kg body weight. Blood samples were collected biweekly for hormonal assay. Uterine biopsies were harvested at days 28 and day 78 of gestation through caesarean section for immunohistochemical analysis using 3 pregnant does randomly selected from each group at each instant. Data were expressed as Means ${\pm}$ Standard Deviations and analyzed using statistical soft ware package, GraphPad Instant, version 3.0 (2003) and progesterone receptor (PR) were scored semi-quantitatively. Results: Dexamethasone treatments had no significant (p > 0.05) effect on progesterone and estrogen concentrations in pregnant Sahel goats but up regulated PR from 2+ to 3+ in second trimester. Conclusion: As dexamethasone adverse effect on placenta is an established fact, the lack of effect on progesterone level in this study may be due to the fact that unlike other species whose progesterone production during pregnancy is placenta - dependent, in goats is corpus luteum - dependent. Consequently dexamethasone adverse effect on placenta reported in literatures did not influence progesterone levels during pregnancy in Sahel goat. The up regulation of progesterone receptor (PR) in Sahel goat gravid uterus is a beneficial effects and that dexamethasone can safely be used in corpus luteum - dependent progesterone secreting pregnant animal species like Sahel goat and camel. Therefore source of progesterone secretions during pregnancy should be considered in clinical application of dexamethasone in pregnancy.

A Bioactive Fraction from Streptomyces sp. Enhances Maize Tolerance against Drought Stress

  • Warrad, Mona;Hassan, Yasser M.;Mohamed, Mahmoud S.M.;Hagagy, Nashwa;Al-Maghrabi, Omar A.;Selim, Samy;Saleh, Ahmed M.;AbdElgawad, Hamada
    • Journal of Microbiology and Biotechnology
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    • 제30권8호
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    • pp.1156-1168
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    • 2020
  • Drought stress is threatening the growth and productivity of many economical crops. Therefore, it is necessary to establish innovative and efficient approaches for improving crop growth and productivity. Here we investigated the potentials of the cell-free extract of Actinobacteria (Ac) isolated from a semi-arid habitat (Al-Jouf region, Saudi Arabia) to recover the reduction in maize growth and improve the physiological stress tolerance induced by drought. Three Ac isolates were screened for production of secondary metabolites, antioxidant and antimicrobial activities. The isolate Ac3 revealed the highest levels of flavonoids, antioxidant and antimicrobial activities in addition to having abilities to produce siderophores and phytohormones. Based on seed germination experiment, the selected bioactive fraction of Ac3 cell-free extract (F2.7, containing mainly isoquercetin), increased the growth and photosynthesis rate under drought stress. Moreover, F2.7 application significantly alleviated drought stress-induced increases in H2O2, lipid peroxidation (MDA) and protein oxidation (protein carbonyls). It also increased total antioxidant power and molecular antioxidant levels (total ascorbate, glutathione and tocopherols). F2.7 improved the primary metabolism of stressed maize plants; for example, it increased in several individuals of soluble carbohydrates, organic acids, amino acids, and fatty acids. Interestingly, to reduce stress impact, F2.7 accumulated some compatible solutes including total soluble sugars, sucrose and proline. Hence, this comprehensive assessment recommends the potentials of actinobacterial cell-free extract as an alternative ecofriendly approach to improve crop growth and quality under water deficit conditions.

Transcriptome Profiling of Differentially Expressed Genes in Cowpea (Vigna unguiculata L.) Under Salt Stress

  • Byeong Hee Kang;Woon Ji Kim;Sreepama Chowdhury;Chang Yeok Moon;Sehee Kang;Bo-Keun Ha
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2022년도 추계학술대회
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    • pp.261-261
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    • 2022
  • Cowpea [Vigna unguiculata (L.) Walp] is one of the most important grain legumes that enhance soil fertility and is well-adapted to various abiotic stress. Also, it is cultivated worldwide as a tropical annual crop, and the semi-arid regions are known as the main cowpea-produced regions. However, accumulation of soil salinity induced by low rainfall in these regions is reducing crop yields and quality. In general, plants exposed to soil salinity cause an accumulation of high ion chloride, which leads to the degradation of root and leaf proteins. In this study, we identified candidate genes associated with salinity tolerance through an analysis of differentially expressed genes (DEGs) in four cowpea germplasms with contrasting salinity tolerance. A total of 553,776,035 short reads were obtained using the Illumina Novaseq 6000 platform for RNA-Seq, which were subsequently aligned to the reference genome of cowpea Vunguiculata v1.2. A total of9,806 DEGs were identified between NaCl treatment and control of four cowpea germplasms. Among these DEGs, functions related to salt stress such as calcium transporter and cytochrome-450 family were associated with salt stress. In GO analysis and KEGG analysis, these DEGs were enriched in terms such as the "phosphorylation", ''extracellular region", and "ion binding". These RNA-seq results will improve the understanding of the salt tolerance of cowpea and can be used as useful basic data for molecular breeding technology in the future.

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사막화방지(沙漠化防止) 및 방사기술개발(防沙技術開發)에 관한 연구(硏究)(I) - 중국(中國)의 사막화현황(沙漠化現況) 및 방지대책(防止對策) - (Studies on the Desertification Combating and Sand Industry Development(I) - Present Status and Countermeasures for the Combating Desertification in China -)

  • 우보명;이경준;전기성;김경훈;최형태;이승현;이병권;김소연;이상호;전정일
    • 한국환경복원기술학회지
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    • 제3권3호
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    • pp.45-76
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    • 2000
  • The purposes of this study were to investigate and understand the present status of various types of "deserts", such as sand desert, gravel desert, rock desert, earth desert, salt desert, desert, rocky desert, gobi desert, sandy desert, clay desert, etc., and the general countermeasures for the combating "desertification" "desertization", and to develop the technologies on the revegetation and restoration for the combating desertification in China. The methods of this study were mainly composed of field surveys on the several experimental sites and research institutes related to combating desertification in China, and examinations on the various technologies for the combating desertification at the Daxing Experimental Station of Beijing Forestry University. The conclusion from this study may be summarized as follows; 1. Status and tendency of desertification in China : China is one of the countries seriously threatened by desertification. Desertification affected areas in China are mainly distributed in arid, semi-arid and dry sub-humid areas in China, covering the most regions of the Northeast China (eastern region of Inner-Mongolia), the northern part of the North China (middle and western region of Inner-Mongolia, Shaanxi, Ningsha, Gansu) and the western part of the Northwest China (Xinzang, Qinghai, Xizang). The total area affected by desertification in China is approximately 2.622 million $km^2$. It covers 27.3% of the total territory of China. Until recently, it is estimated that the annual spreading ratio of desertification in China is 2,460 $km^2$. Therefore, desertification is mostly serious problems facing to the Chinese people. 2. The causes and environmental effect of desertification : The desertification in China is mainly caused by compound factors, including natural condition and human activities. In China, the desertification is started by the decrease of precipitation, continuous dry and drought, strong wind, wind and water erosion, land degradation and loss of natural vegetation caused by climate variation, and accelerated by the human activities, such as over-cultivating, over-grazing, over-cutting of woods, irrational use of water resources. Because desertification has affected the geographical features, soil nutrients contents, salinity, vegetation coverage and the functions of ecosystem, the environmental deteriorations in the desertification affected areas are very seriously. 3. The fundamental strategies of combating desertification in China are the increase of education and awareness of people through various mass media, the revision of laws to guarantee operation of Desertification Combating Law and to improve many relating laws and regulations, the application of advanced technologies and training of experts, the establishment of discriminative policies, and increasing arrangement of budget-investment, and so on. China, as a signed country in UNCCD, has made efforts for the combating desertification. Korea is also signed country in UNCCD, so we should play an important role in the desertification combating projects of China for the northest asia and global environmental conservation as well as environmental conservation of Korea.

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터키 샹르울파주 목화농업의 전개와 지역사회의 변화 (Development of Cotton Farming and Transformation of Rural Area in Sanliurfa Prefecture, Turkey)

  • 강숙경
    • 대한지리학회지
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    • 제48권1호
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    • pp.87-111
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    • 2013
  • 터키의 동부 지역과 서부 지역 간의 경제 문화적 지역격차는 국가균형개발을 위해 터키정부가 해결해야 할 주요 과제 중 하나이다. 남동 아나톨리아 개발계획은 티그리스강과 유프라테스강의 수자원을 이용하기 위한 수력개발에서 시작하여, 1980년대 지역균형개발과 사회통합을 목표로 하는 종합적인 지역개발계획으로 발전하였다. 본 연구는 반건조 기후 지역으로 관개용수의 공급 없이는 상품작물의 재배가 불가능한 터키의 남동부 지역이 개발계획에 의해 주요 목화생산지로 변화한 것에 주목하여, 이를 가능하게 한 남동 아나톨리아 개발계획의 배경, 과정, 내용과 그에 따른 목화 생산성의 변화 등을 살펴보았다. 또한, 남동 아나톨리아 개발계획의 중심축으로써, 정부의 집중적인 투자가 이루어지고 있는 샹르울파주를 대상으로, 목화농업의 성장배경과 전개과정을 살펴보았다. 샹르울파주는 터키 전체 목화생산량의 37.6%를 생산한다. 이는 하란평원을 중심으로 시행된 정부의 경지정리 사업, 관개용수로 사업, 도로와 농로 등 농업을 위한 기반시설 확충이 큰 역할을 담당하였다. 또한, 목화재배에 따른 보조금 지급도 목화재배가 활성화된 주요 요인 중 하나이다. 관개용수의 공급은 이 지역 인구이동에 커다란 변화를 가져왔다. 관개 이전, 계절적 노동을 위해 다른 지역으로 이주했던 심각한 인구유출 현상은 관개 이후, 관개 지역을 중심으로 한 지역 내 이동과 다른 지역으로부터의 인구 유입 형태로 그 내용이 변화하였다. 관개용수는 국가수자원 총국(DS$\dot{I}$)으로부터 관개용수 관리 운영권을 이양받은 관개용수 조합(Sulama Birli$\breve{g}$i)이 각 농가에 공급한다. 그러나 관개용수 조합은 부족집단(Aşiret)을 기본으로 하는 전통적 봉건사회 구조하에 있으며, 이로 인해 농민을 위한 효율적 경영이 이루어지지 않고 있다. 또한, 이는 농민 자치조직의 형성에도 걸림돌로 작용하고 있다.

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Effect of Flushing on Nutrient Utilization and Reproductive Performance of Ewes Grazing on Community Rangeland

  • Chaturvedi, O.H.;Bhatta, Raghavendra;Verma, D.L.;Singh, N.P.
    • Asian-Australasian Journal of Animal Sciences
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    • 제19권4호
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    • pp.521-525
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    • 2006
  • The present study was undertaken to evaluate the effect of flushing of ewes with concentrate pellets just before the mating season on their nutrient utilization and reproductive performance on farms. Forty-eight Malpura ewes, 1-5 years old were randomly divided into 2 groups of 24 each (G1and G2). Ewes in both the groups were grazed on natural rangeland from 07.00 to 18.00 hr followed by night shelter in animal shed. G1 ewes were maintained on sole grazing while G2 ewes, in addition to grazing, received concentrate pellets at the rate of 1.5% of their body weight. The mean biomass yield of the community rangeland was 0.46 ton DM/hectare. The intakes of DM (g/kg $W^{0.75}$), DCP (g/kg $W^{0.75}$) and ME (MJ/kg $W^{0.75}$) were higher (p<0.01) in G2 as compared to that of G1 being 86.5, 10.2 and 1.15 and 57.5, 4.7 and 0.75, respectively. The digestibility of DM, OM, CP, NDF and hemicellulose were also higher (p<0.01) in G2 as compared to that of G1 being 57.2, 76.7, 78.9, 51.9 and 81.6 and 50.8, 68.7, 68.4, 45.4 and 74.4, respectively. The conception rate was higher (79.2%) in flushed ewes as compared to that of non-flushed (66.7%). Five of the pregnant ewes died and another 5 aborted in G1 while in G2, 5 ewes aborted with no mortality. The lambing was higher (73.7%) in G2 than that in G1 (37.5%). The birth weight of lambs was higher (p<0.05) in G2 (3.47 kg) than that in G1 (2.95 kg). Further, the birth weight of male lambs was higher (3.28) than that of female lambs (3.14). It is concluded that the biomass yield of the community rangeland in semi-arid region of India is low and insufficient to meet the nutrient requirement of ewes prior to mating season. However, concentrate supplementation at the rate of 1.5% of body weight to ewes during this critical stage enhanced their plane of nutrition, reproductive performance, body condition and birth weights of lambs.

Effects of Mineral Supplementation on Milk Yield of Free-ranging Camels (Camelus dromedarius) in Northern Kenya

  • Onjoro, P.A.;Njoka-Njiru, E.N.;Ottaro, J.M.;Simon, A.;Schwartz, H.J.
    • Asian-Australasian Journal of Animal Sciences
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    • 제19권11호
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    • pp.1597-1602
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    • 2006
  • The effects of different mineral supplementations on the milk yield of free-ranging Somali camels were investigated in two phases in a semi-arid region of northern Kenya during the dry and wet seasons in 2002 and 2003. In phase 1, twelve (12) lactating camels were selected at random to form four (4) groups each consisting of three camels. The first group served as the control and as a result received no mineral supplementation. In addition to the control diet the other groups received oral doses of minerals as follows over a 60-day period: T1 (P), T2 (High Cu low Co) and T3 (Low Cu high Co). The daily milk yield and blood mineral profiles were measured during the wet and dry seasons. The mean daily milk yield increased from 3.4 L/d to $4.3{\pm}0.3L/d$ and 5.2 L/d in the dry and wet seasons, respectively. Fifteen (15) lactating camels were selected at random to form five groups each consisting of three replicates. The control group did not receive any mineral supplement. The other four groups in addition to the control diet, received the following treatments: T4 (Common Salt), T5 (High Co), T6 (High Co+P) and T7 (Low Co+P). Mineral supplement T6 produced significantly higher milk yield ($5.4{\pm}0.5$ and $6.5{\pm}0.7L/d$) during the dry and wet seasons. Both T6 and T7 had significantly higher milk yield than T4 and T5. During both phases, the blood Ca and P level significantly increased in camels receiving T1, 6 and 7. Animals that received only the trace mineral supplements had lower blood P compared to the ones receiving supplementary P and also the control. Supplementation of lactating camels with Co and P significantly (p<0.05) increased milk yield). Effect of common salt, commonly given by farmers, on milk yield was insignificant. It was concluded that mineral supplementation to lactating camels was beneficial, and that mineral supplements should include P and Co. Further research is required to establish P and Co requirements of lactating camels.

위성자료를 이용한 몽골의 일사량 분포 특성 (The Character of Distribution of Solar Radiation in Mongolia based on Meteorological Satellite Data)

  • 지준범;전상희;최영진;이승우;박영산;이규태
    • 한국지구과학회지
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    • 제33권2호
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    • pp.139-147
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    • 2012
  • 몽골의 태양-기상자원지도는 위성자료 및 재분석 자료를 이용하여 개발되었다. 태양복사량은 단층 태양복사모델을 이용하였으며 입력자료는 SRTM, MODIS, OMI, MTSAT-1R 등의 위성관측자료와 전구모델의 재분석자료를 이용하였다. 계산된 결과는 NCEP/NCAR 재분석 DSWRF 자료를 이용하여 계산된 일사량을 검증하였다. 몽골은 서부의 산악지역과 중남부의 사막 및 반사막지대로 이루어져 있으며 대륙 내부에 위치하여 강수량이 적고 맑은 날이 많아 동일 위도상의 다른 지역과 비교하여 높은 일사량이 나타난다. 서부 산악지역은 고도가 높아 태양에너지가 많이 도달되는 곳임에도 불구하고 일사량이 낮게 나타난다. 그 이유는 산악지역에 존재하는 연중 적설이 위성자료의 구름탐지 알고리즘에서 구름으로 오탐지 되기 때문이다. 따라서 청천지수뿐만 아니라 일사량 또한 낮게 계산된다. 남부지역은 상대적으로 높은 가강수량과 에어로솔 광학두께가 나타났으나 다른 지역에 비해 위도가 낮고 청천지수가 높아 일사량이 높게 나타나는 것으로 분석된다. 계산된 월 누적 일사량은 547.59 MJ로써 전 지점에서 약 2.89 MJ로 높게 계산되었으며 상관성은 0.99였고 평방근오차(Root Mean Square Error; RMSE)는 6.17 MJ 이었다. 월별 통계 값을 계산하였을 때 상관성이 가장 높은 월은 10월로 0.94였고 3월은 0.62로 가장 낮게 나타났다.

우리나라에 적합한 OECD 농업용수 사용지표의 설정 (Application of OECD Agricultural Water Use Indicator in Korea)

  • 허승오;정강호;하상건;송관철;엄기철
    • 한국토양비료학회지
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    • 제39권5호
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    • pp.321-327
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    • 2006
  • 농업환경지표가 OECD 회원국간의 농업환경 비교와 이를 통한 농업환경 개선과 농업정책 수립에 대한 권고의 수단으로만 작용을 하지만 이것이 향후 통상 무역과 연계될 것은 추측 가능한 사실이다. OECD 농업환경지표를 우리나라에 그대로 적용했을 때 얻어진 지표 값이 우리나라의 농업환경을 사실대로 반영하지 못한다면 우리가 받을 피해는 미래에도 작용할 것이므로 이에 대한 새로운 제안을 통해 우리나라에 적합한 지표를 설정해야 한다. OECD에 의해 제안된 농업용수 사용 강도 지표는 논이나 밭에서 이용되거나 배수 유출되는 물의 특성을 모두 반영한 방법이 아니므로 몬순 기후지대에 속하는 한국에 적당하지 않다. 특히, 여름철 집중호우시기에 년 강우량의 2/3가 내리는 강우 특성은 이를 담수해 저장하는 능력을 가진 농경지의 수자원 보유능과 기타의 농업적 특성을 고려한 계산방법으로 농업용수를 산정해야 한다. 논의 경우 강우가 내리거나 관개가 되었을 때 담수나 침투를 통해 물을 지하로 배수해 지하수를 형성하거나 지표의 배수로나 하천을 통해 강이나 저수지로 상당량의 물을 흘려보내 다시 이용할 수 있도록 해준다. 즉, 농업용수로 계산되어 있는 물의 상당량은 다른 농경지나 생활용수 또는 공업용수나 하천 유지용수로 다시 이용된다. 따라서, 물 사용강도에 이용되는 농업용수는 농경지에서 소모되지 않고 지하수로 흘러 들어가거나 하천으로 유입되는 배출수를 고려하여 계산하는 것이 합리적이다. 이렇게 계산하면 22.9%(2001년)로 OECD 계산방법으로 얻어진 47%보다 24.1%가 낮아진다. 합리적인 농업용수 스트레스 지표를 산출하기 위해서는 각 나라마다 다른 나라와 강을 공유하고 있는지의 여부와 농업을 위한 주 취수원이 무엇인지를 살펴보아 그 나라에 적합한 스트레스 지표를 산출하도록 유도하는 것이 바람직할 것이다. 그러나, 실제 물에 대한 스트레스는 강우량, 수계별 수자원 부존량, 사용가능량, 농업용수 총공급수량, 환경 유지용수를 위한 기준 갈수량 확보 가능성, 농업용수 관리현황 및 저수율 분석, 수계별 농업용수 사용 가능량 및 기상 등이 복잡하게 작용할 것이므로 이 모든 인자들을 포함한 지표를 만들기는 쉬운 일이 아니다. 따라서, 우리나라는 OECD의 스트레스 지표와는 달리 환경 위해성 판단이 필요 없고, 계산이 복잡하지 않으며 우리의 환경에 적합하도록 주 취수원인 농업용 저수지의 저수율로 농업용수 스트레스 지표를 산정 했다. 농업용수 사용 기술적 효율지표는 작물의 재배 생리특성 및 이용특성과 지역마다 차이가 나는 기후의 특성을 반영하지 않은 계산의 결과이다. 그러므로 이러한 특성들을 반영하는 기술적 물 이용효율 지표를 만들기 위해서는 각 지역 또는 나라마다 작물별로 기준이 되는 물 소요량을 산정한 후 그 소요량에 대한 공급된 양의 비율로 WUTE를 결정하는 것이 합리적이다. 지역별, 작물별 특성을 포함해야 하는 농업용수 사용 경제적 효율 지표는 소비된 물을 분모로 삼아 계산에 이용하는 대신에 농업용수 사용 기술적 효율에서 제안한 각 지역 또는 나라마다 작물별로 기준이 되는 물 소요량을 산정한 후 그 소요량에 대한 공급된 양의 비율을 계산식의 분모에 적용하고, 벼의 경우는 생산물의 가격 대신에 지하수가 되는 양과 하천수가 되는 양에 대한 경제적 평가에 더해 논에 많은 양의 물이 관개됨으로서 발생하는 수변 생태계에 의한 환경유지 기능과 온도와 습도가 높은 한국의 기후 특성에서 전체 에너지 밸런스를 유지하는데 기여하는 관개수의 가치에 대한 평가와 더불어 생산물의 가격을 포함하는 것이 합리적일 것이다.