نتایج جستجو برای: but also prevent soil and water pollutions

تعداد نتایج: 17064207  

2008
Haishen Lü Yonghua Zhu Todd H. Skaggs Zhongbo Yu

In the hilly regions of China, developing sustainable agriculture requires implementing conservation management practices that prevent soil erosion and conserve soil and water resources. In the semiarid northwest Loess Plateau, the primary conservation management practice is terracing. Numerical simulation of soil water dynamics in terraces is potentially an efficient means of investigating the...

مجید افیونی, , حسین خادمی, , منوچهر امینی, ,

Heavy metals including cadmium (Cd) and lead (Pb) are entering agricultural soils from different routes and mainly due to human activities. Accumulated Cd and Pb in the soil would eventually enter the human and animal food chains and pose threat to their health. Therefore, evaluating heavy metal accumulation is necessary to prevent soil and environmental pollutions and should be considered by r...

2010
Hideo Utsumi Yoshiteru Tsuchiya

Water is an essential material for all organisms on earth to sustain life, and a satisfactory water supply must be made available to consumers. It is required that drinking water not be contaminated by microbes or chemical substances harmful to human health. Pathogenic bacteria, viruses and protozoa in drinking water cause waterborne infectious diseases. The pollution source, pathogenicity, and...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه کاشان - دانشکده ادبیات و زبانهای خارجی 1392

abstract this study aimed at investigating the possible relationship between self-assessment in writing and self-regulation of iranian efl learners. the main purpose of the study was not only to report and inform about this relationship, but also to investigate and find practical outcomes of the incorporation of self-assessment in writing, such as improving writing skill. the research was carr...

Caspian Sea is the largest enclosed body of water on the earth. Since the collapse of Soviet Union in 1991 and discovering large oil and gas fields, some issues such as political, economic and environmental events, made the Caspian Sea important. The ecology of the Sea are being endangered due to several issues such as petroleum extraction, river and sea pollutions, water level rise, biological...

Introduction Oilseeds after Cereals make up the second world food supply. Sesame is one of the oldest cultivated plants and possibly the world's oldest oil plants. Nowadays, sesame is used as a source of edible oil.  Sesame home is warm and semi-warm areas, but its cultivation spread to temperate regions (Weise, 2000). To effectively and efficiently use the available water sources to me...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه صنعتی اصفهان - دانشکده ریاضی 1390

the main objective in sampling is to select a sample from a population in order to estimate some unknown population parameter, usually a total or a mean of some interesting variable. a simple way to take a sample of size n is to let all the possible samples have the same probability of being selected. this is called simple random sampling and then all units have the same probability of being ch...

Soil conservation is the only known way to protect the productive land. In country like Ethiopia, where droughts and floods cause food scarcity problem, soil and water conservation not only increases crop yield, but also prevents further deterioration of land. Soil and water conservation preserve soil moisture and drain water sustainably to avoid soil erosion and depletion of soil nutrients. So...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه شهید چمران اهواز - دانشکده ادبیات و علوم انسانی 1389

methodology non-native participants in this study were sixty ba students majoring in english literature and teaching english as a foreign language at khayyam university of mashhad. they were senior students, between 21 to 24 years old, who had studied english for at least three and a half years and had passed several courses including grammar, reading, conversation, and writing. this was assum...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه امام صادق علیه السلام - دانشکده الهیات و معارف اسلامی 1391

muhammad ibn muhammad ibn numan, known as "shaykh mufid," one of the great imamiye theologians and jurists in the fourth and early fifth century , had comprehensive mastery of both rational and traditional topics and exerted his influence upon both his contemporary and future scholors. he is considered to be one of the top imamiye scholars who spent his lifetime teaching, learning and authorin...

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