• 제목/요약/키워드: Semiarid

검색결과 31건 처리시간 0.028초

Nutrient Requirements for Growth of Lambs under Hot Semiarid Environment

  • Karim, S.A.;Santra, A.
    • Asian-Australasian Journal of Animal Sciences
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    • 제16권5호
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    • pp.665-671
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    • 2003
  • A factorial experiment was conducted to assess nutrient utilization by growing lambs maintained on three levels each of digestible energy (high: HE, medium: ME, low: LE) and protein (high: HP, medium: MP, low: LP) in nine combinations (HEHP, HEMP, HELP, MEHP, MEMP, MELP, LEHP, LEMP, LELP). The experiment was conducted during the hot season in a semiarid location. Daily dry matter intake (DMI) was similar in all the groups in terms of unit body weight or metabolic body size. Digestibility of DM and nitrogen free extract increased (p<0.01) from low to medium and high energy regimen while the CF digestibility followed a reverse trend. The digestibility of crude protein (CP) decreased from high to medium and low protein regimens while it was similar in terms of energy variation. Nitrogen intake was higher in high followed by medium and low protein regime while fecal and urinary nitrogen loss were similar in all the treatment groups. Lambs in all the three levels of protein were in positive N balance and percent N retention was higher (p<0.01) in high followed by medium and low protein levels whereas it was similar in terms of energy variation. Initial body weight was similar in all the groups while final weight, total gain in the experiment and average daily gain (ADG) were higher in high than medium and low energy regimens. It is concluded that crossbred lambs required 75.1 g DM, 9.6 g CP, 6.3 g DCP and 711 KJ DE/kg W $^{0.75}$or 11.0 g CP/MJ DE or 7.2 g DCP/MJ DE for 93 g average daily gain in a hot semiarid environment.

증발산량 산정에 있어서 기상학적 요인들의 민감도 해석 (Sensitivity Analyses of the Meteorological Factors in the Estimation of Evapotranspiration Rates)

  • 임창수
    • 한국환경과학회지
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    • 제5권5호
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    • pp.657-662
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    • 1996
  • 여름과 겨울철에 준건조 유역들 (Lucky Hills and Kendall)로부터 측정되어진 기상학적 그리고 flux data를 이용하여 증발산 산정을 위한 변수들의 민감도를 연구하였다. 상대적 민감도 분석을 이용하여 Pen농an의 잠재증발산 산정에 필요한 네 가지 기상학적 그리고 flux변수(순방사, 풍속, 공기온도 그리고 상대습도)들의 중요도가 검증되어졌다. 두 다른 유역으로부터의 연구 결과에 의하면, 여름철에 Pen-mim의 잠재증발산략의 변화는 공기 온도와 순방사에 의해서 지배되어지고, 겨울철에는 상대습도와 공기온도에 의해서 지배되어지는 것으로 나타났다.

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계절과 수문기상학적 조건에 따른 지역 증발산의 특성화 (Characterization of Local Evapotranspiration Based on the Seasonal and Hydrometeorological Conditions)

  • 임창수;이종태;윤세의
    • 물과 미래
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    • 제29권2호
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    • pp.235-247
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    • 1996
  • 여름우기와 겨울기간 동안에 준건조 기후 유역들(Lucky Hills 그리고 Kendall) 로부터 측정된 기상학적 그리고 토양 함수량 자료를 이용하여 증발산의 조절변수들 간에 상관관계와 매일의 실제 증발산량 산정을 위한 변수들의 영향을 연구하였다. 기상학적 요소와 토양 함수량의 중요도를 알아보기 위하여 단순, 다변량선형상관분석들이 적용되어졌으며, 얻어진 정보는 다변량선형상관모델을 개발하기 위하여 사용되어졌다. 유효 에너지와 대기 증기압 차는 두 다른 유역과 계절 기간 동안에 증발산을 지배하는 중요한 변수인 것으로 판명되어졌다. 그러므로 준건조 기후 지역에 있어서 증발산 과정의 중요한 변수로는 단순히 Penman에 의해서 제안된 잠재 증발산 모형의 에너지 항에 있어서 유효 에너지와 공기 동력 항에 있어서 대기증개압차인 것으로 나타났다.

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Comparison of Daily Soil Water Contents Obtained by Energy Balance-Water Budget Approach and TDR

  • Rim, Chang-Soo
    • Korean Journal of Hydrosciences
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    • 제8권
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    • pp.57-68
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    • 1997
  • The daily soil water contents were obtained from the time domain reflectometry(TDR) method and energy balance-water budget approach with eddy correlation at the two small semiarid watersheds of Lucky Hills and Kendall during the summer rainy period. There was a comaprison of daily soil water content measured and estimated from these two different approaches. The comparison is valuable to evaluate the accuracy of current soil water content measuring system using TDR and energy balance-water budget approach using eddy correlation method at a small watershed scale. The degree of simiarity between the regressions of these two methods of measuring soil water content was explained by determining the correlations between these methods. Simple linear regression analyses showed that soil water content measured from TDR method was responsible for 58% and 63% of the variations estimated from energy balance-water budget approach with edy correlation at Lucky Hills and Kendall, respectively. The scatter plots and the regression analyses revealed that two different approaches for soil water content measurement at a small watershed scale have no significant difference.

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An Estimate of the Mediation Effect of Risk Tolerance among Marital Status, Gender, and Investing Behavior

  • Heo, Wookjae;Grable, John E.;Nobre, Liana;Ruiz-Menjivar, Jorge
    • International Journal of Human Ecology
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    • 제17권1호
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    • pp.1-14
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    • 2016
  • This paper presents a series of path models that were developed to test whether financial risk tolerance mediates the association between the following four variables and investing behavior: (a) male and married, (b) female and married, (c) male and single, or (d) female and single. Data for this study were obtained from a proprietary consumer survey of risk-tolerance attitudes. Four path models were developed to test relationships among the variables in 2008, 2009, 2010, and 2011. These years were chosen to represent the depth and recovery periods in the Great Recession. The total number of respondents was 29,641. Findings showed that financial risk tolerance was positively associated with risky investing behavior (i.e., equity ownership) in each of the four periods. The associations among the gender-marital status variables and investing behavior were mixed; however, findings did indicate that risk tolerance mediates these relationships by sometimes amplifying and occasionally attenuating risky behavior. Based on the findings, implications and limitation are presented.

Land use classification using CBERS-1 data

  • Wang, Huarui;Liu, Aixia;Lu, Zhenhjun
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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    • pp.709-714
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    • 2002
  • This paper discussed and analyzed results of different classification algorithms for land use classification in arid and semiarid areas using CBERS-1 image, which in case of our study is Shihezi Municipality, Xinjiang Province. Three types of classifiers are included in our experiment, including the Maximum Likelihood classifier, BP neural network classifier and Fuzzy-ARTMAP neural network classifier. The classification results showed that the classification accuracy of Fuzzy-ARTMAP was the best among three classifiers, increased by 10.69% and 6.84% than Maximum likelihood and BP neural network, respectively. Meanwhile, the result also confirmed the practicability of CBERS-1 image in land use survey.

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북부 아르헨티나 붕산염 광상 조사: 살리나스그란데스 광상을 중심으로 (Survey of Borate deposit in Northern Argentina: Salinas Grandes Borate deposit)

  • 박상준;이한영
    • 한국지구과학회지
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    • 제30권7호
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    • pp.801-809
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    • 2009
  • 북부 아르헨티나 후후이주 동부에 위치하는 살리나스그란데스 붕산염(borate) 광상은 플라야 주변부에 배태되는 플라야(playa)형 증발광상이다. 이 광상에서 산출되는 붕산염광물은 주로 울렉사이트(ulexite, $NaCaB_5O_9{\cdot}H_2O$)로 붕소의 주공급원은 주변 화산암일 것으로 추정된다. 아르헨티나 후후이주 동부는 아건조 기후의 알티플라노-푸나 고평원에 위치한다. 중생대 및 신생대 화산암체는 붕소의 주요 공급원으로 생각되며, 플라야는 이들 붕소가 침전되는 주요분지 역할을 하여 이 지역은 붕소의 이동과 침전을 위한 좋은 지형적 지구조적 조건을 보인다. 따라서 향후 이 지역의 붕산염 광체에 대한 지속적인 탐사가 필요 할 것으로 생각된다.

NDVI time series analysis over central China and Mongolia

  • Park, Youn-Young;Lee, Ga-Lam;Yeom, Jong-Min;Lee, Chang-Suk;Han, Kyung-Soo
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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    • pp.224-227
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    • 2008
  • Land cover and its changes, affecting multiple aspects of the environmental system such as energy balance, biogeochemical cycles, hydrological cycles and the climate system, are regarded as critical elements in global change studies. Especially in arid and semiarid regions, the observation of ecosystem that is sensitive to climate change can improve an understanding of the relationships between climate and ecosystem dynamics. The purpose of this research is analyzing the ecosystem surrounding the Gobi desert in North Asia quantitatively as well as qualitatively more concretely. We used Normalized Difference Vegetation Index (NDVI) derived from SPOT-VEGETATION (VGT) sensor during 1999${\sim}$2007. Ecosystem monitoring of this area is necessary because it is a hot spot in global environment change. This study will allow predicting areas, which are prone to the rapid environmental change. Eight classes were classified and compare with MODerate resolution Imaging Spectrometer (MODIS) global land cover. The time-series analysis was carried out for these 8 classes. Class-1 and -2 have least amplitude variation with low NDVI as barren areas, while other vegetated classes increase in May and decrease in October (maximum value occurs in July and August). Although the several classes have the similar features of NDVI time-series, we detected a slight difference of inter-annual variation among these classes.

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