عنوان مقاله
معیار آب مجازی و تحلیل های تغییر ساختار برای محصولات
فهرست مطالب
مقدمه
موقعیت توسعه منابع آبی و محصولات کشاورزی در جلگه سانجیانگ
معیار وابسته برای آب مجازی محصولات کشاورزی اصلی
نتایج و تحلیل ها
نتیجه گیری و بحث
بخشی از مقاله
در این رابطه
∆ شیب منحنی فشار بخار آب اشباع وابسته به دما[KPa/T (℃)] ، 〖𝐸𝑇〗_0 کمیت تبخیر و تعریق محصولات مرجع(mm/d)، 𝑅_𝑛 تابش خالص سطح محصولات (MJ/m2.d) ، G شار گرمایی خاک(MJ/m2.d) ، T میانگین دمای هوا [T (℃)] ، 𝑈_2 باد با 2 متر ارتفاع (m/s) ، 𝑒_𝑎 فشار بخار آب اشباع (KPa) ، 𝑒_𝑏 فشار آب اندازه گیری شده (KPa)، γ ثابت های رطوبت خشک KPa/T) ) میباشد.
محاسبه آب مجازی محصولات اصلی
با تعیین مقدار آب مجازی محصولات کشاورزی درست اندازه گیری شده در جلگه سانجیانگ، عناصر منابع آبی را می توان در حیطه انتخاب استراتژی تجاری غذا و برنامه ریزی کاشت منطقه ای لحاظ نمود. فرمول محاسبه مقدار آب مجازی محصولات کشاورزی به شکل زیر می باشد:
کلمات کلیدی:
Virtual water measure and analyses of structure change for regional agricultural products in Sanjiang plain Jing Zhao College of Water Conservancy & Architecture, Northeast Agricultural University Harbin, P.R. China, 150030 snow_spring_25@126.com Qiang Fu College of Water Conservancy & Architecture, Northeast Agricultural University Harbin, P.R. China, 150030 fuqiang@neau.edu.cn Baozhu Yu College of Water Conservancy & Architecture, Northeast Agricultural University Harbin, P.R. China, 150030 Yubaozhu_job@163.com Abstract—Virtual water is the new method of realizing sustainable development of water resources. It plays an important role in changing the uneven distribution of the spatial pattern of water resources in our country. Through confirming the virtual water content in units’ crops of Sanjiang Plain, this paper furthermore finds the virtual water content over the years of all types of crop, and undertakes an analysis to structural changes of crop on this foundation; comparing with the average virtual water content of crop, draws the total virtual water content of food crop in Sanjiang Plain displayed increasing tendency since 2003, and the rise range is bigger, indicating that the food crops of this region generally have water-saving planting advantage. Keywords- virtual water; agricultural products; Sanjiang plain I. INTRODUCTION Virtual water firstly put forward by British scholar Allan is new concept of water resources management, and is the water used to produce goods and service [1]. The research of virtual water trade can promote efficient use water resource. Food as the main water consumption, there are a lot of virtual water implicit within it. At present agricultural products are main water labor-intensive goods in our country [2]. Sanjiang plain as the base of the important commodity grain production in China, take important mission for grain production and output. Although the region are plenty of rainfall, but in recent years the status quo of water resources is not optimistic. A higher percentage of agricultural water accounts for more than 90% of total water consumption. So in this paper total amount and structure change of agricultural products virtual water are analyzed, to systematically understand local water resources utilization, and then help to further develop virtual water related research. To adjust and optimize the planting structure based on virtual water, improving the utilization ratio of water resources provides new train of thought for water resources management. II. THE DEVELOPMENT SITUATION OF WATER RESOURCES AND AGRICULTURAL PRODUCTS IN SANJIANG PLAIN Sanjiang plain has total area of 10.8 ten thousand km2 , cultivated land area of nearly 3.51 million hm2 . The soil quality is good, the terrain is flat and concentrated, which is suitable for the agricultural production of mechanization and intensification. It is rich in water resource, and can meet the farming and animal husbandry requirements, produce high quality agricultural and sideline products. So we can reduce water resources pressure in domestic arid areas, through the way of trade to implement virtual water strategy, and meanwhile develop virtual water economy of Sanjiang plain. The water resources mainly include abundant local precipitation and transit water in Sanjiang plain. Mean annual precipitation is 556 mm, about 60 billion m3 water resources; Transit water is about 278.5 billion m3 , mainly including Heilongjiang River 147.6 billion m3 , Songhua River 68.7 billion m3 , Wusuli River 62.2 billion m3 . Sanjiang plain is well irrigation area, almost no loss. In this region there is the great advantage and potential to implement virtual water strategy. III. RELATED MEASURED FOR VIRTUAL WATER OF MAIN AGRICULTURAL PRODUCTS A. The determination of crop water requirement Crop water requirement is calculated based on transpiration of water evaporation in the growth period, is evapotranspiration ETc accumulated in the whole process of crop growth [3]. In this region the reference crop evapotranspiration of main crops is calculated according to the method of reference crop evapotranspiration recommended by FAO. ET0 can be calculated by Penman formula recommended [4]. ǻ Ȗ(1 )0.34U )-( 273 900 ǻ(R408.0 - G) Ȗ 2 n 0 ++ + + = b
