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1.
Integrated Indicators-based Gradation of Cultivated Land Quality in Mountainous Region of Southwestern China 总被引：1，自引：0，他引：1
SHAO Jing＇an WEI Chaofu XIE Deti ZHOU Yan 《山地科学学报》2006,3(3):259-270
1 Introduction The gradation of cultivated land is to assess the suitability of cultivated land for agricultural production in terms of natural and economic prop-erties of land (Feng et al. 2004). It can be used to evaluate sustainability of land use and … 相似文献
2.
YU Bohua LU Changhe 《中国地理科学(英文版)》2006,16(4):299-305
1 Introduction FAO defined food security not only in terms of access to and availability of food, but also in terms of resources distribution to produce food and the purchasing power on food where it is not produced (Shi et al., 1996; Ning, 2004). Obviously, to guarantee everyone adequate food is the primary aim and most important content of food security (Xie et al., 1999). Thus, to increase food supply is a precondition for food security by domestic food production and international food t… 相似文献
3.
WU Jinkui DING Yongjian WANG Genxu SHEN Yongping Yusuke YAMAZAKI Jumpei KUBOTA 《中国地理科学(英文版)》2006,16(3):243-248
1 Introduction Most of the solar radiation that ecosystem seizes is con- sumed on latent, sensible and soil heat flux. Among them, latent heat flux shares the biggest part (Gutierrez and Meizer, 1994; Ham et al., 1991; Rachidi et al., 1993). The radiation budget and the energy balance are crucial to water conversion and effective water utilization. Also, they are important parts of research of water-saving ag- riculture (Mo et al., 1997). At present, the researches on radiation budget and e… 相似文献
4.
张毅 《中国海洋湖沼学报》2011,29(5):1128-1130
Herein we would like to comment on the paper "Estimation of potential distribution of gas hydrate in the northern South China Sea" by Wang et al. 2010 in Chinese Journal of Oceanology and Limnology, 28(3): 693-699. The purpose of this comment is to point out that the given probabilities of gas hydrate occurrence in the northern Zhujiang Mouth Basin and the Yinggehai Basin in the figure of Wang et al. (2010) are improper. After introducing our work of estimation of gas hydrate stability distribution in the northern South China Sea, we suggest that Wang et al. (2010) dismissed the basic P-T rule for the existence of gas hydrate. They should consider more the variables of water depth, seabed temperature and geothermal gradient in their gas hydrate distribution model in future studies. 相似文献
5.
Carbon dioxide partial pressure and carbon fluxes of air-water interface in Taihu Lake, China 总被引：2，自引：0，他引：2
1 INTRODUCTION Carbon dioxide (CO2) is principal greenhouse gas. Its air-water exchange is important in terrestrial ecosystems for climate change (Frankignoulle et al., 1998; Schimel et al., 2001). The direction of CO2 gas movement depends on the CO2 concentration gradient between air and surface water. The amount of CO2 exchange is related to the gas exchange coefficient, k. All lakes, with their small area but large atmospheric CO2 flux are important to under-stand the CO2 fluxes … 相似文献
6.
LIU Chunlan XIE Gaodi HUANG Heqing 《中国地理科学(英文版)》2006,16(4):314-319
1 Introduction The sensitivity of ecosystems to global climate change is one of important issues for research. Many studies have indicated that wetland ecosystem is one of the most vulnerable systems (Brock and Van, 1992; Vourltis and Oechel, 1997; Burkeet, 2000; Lahmer et al., 2001; Zhang et al., 2001; Deng et al., 2003). The shrinking and drying up of wetlands in arid and semiarid areas of China have been widely observed in the recent years (Wang, 1990; Wang and Zhang, 1991; Jin, 1993; … 相似文献
7.
1 INTRODUCTION One of the most intriguing phenomena in the late Neoproterozoic (~750 to 543 Ma) is the globa occurrence of thin carbonates that directly overlie glacial deposits in almost every continent (Kennedy 1996; Hoffman et al., 1998; Hoffman and Schrag 2002; Brasier and Shields, 2000; James et al., 2001 Jiang et al., 2003; Nogueira et al., 2003). These “cap carbonates”, commonly several to tens of meters thick, have attracted enormous interests because o their unusually negati… 相似文献
8.
Introduction A set of reddish clay-silt-sized sediments named red clay underlying the Quaternary loess-paleosol sequence widely distribute in the Chinese Loess Plateau. The thickness of the red clay sediments ranges from decades of meters to over 100 m (Evan et al.1991,Mo and Derbyshire 1991, SUN et al. 1997&1998, DING et al. 1999, GUO et al. 2001, QIANG et al. 2001). Previous studies show that not only loess-paleosol (e.g.LIU et al.1985,AN et al.1990,DING et al.1992),but also red … 相似文献
9.
1 INTRODUCTION Bioavailability to the biota and the biogeo-chemistry of trace metals in marine environment areaffected by their chemical speciation in the naturalsystem (Bruland et al., 1991; Van den Berg andDonat, 1992; Wells et al., 1998). Therefore, thesetwo parameters, the ligands concentrations andconditional stability constants, are important todetermine the complexing capacity. Sea surface microlayer (SML), the thin interfa-cial boundary between ocean and atmosphere, playsan imp… 相似文献
10.
Genetic Analysis of Four Populations of Redlip Mullet(Chelon haematocheilus) Collected in China Seas
MENG Wei) GAO Tianxiang) * and ZHENG Bing) ) Key Laboratory of Mariculture Ministry of Education Ocean University of China Qingdao P. R. China ) Shandong Ocean Exploration Center Qingdao P.R.China 《中国海洋大学学报(英文版)》2007,6(1):72-79
1 Introduction The redlip mullet, (Chelon haematocheilus) (Tem-minck et Schlegel, 1845), belongs to the family Mugili-dae. It is mainly distributed in the coastal areas of Korea, Japan and China (Wang et al., 2000). Because of the good adaptation to envir… 相似文献
11.
LUO Jinming DENG Wei ZHANG Xiaoping YANG Fan LI Xiujun 《中国地理科学(英文版)》2006,16(4):342-346
1 Introduction The preferential flow tends to result in the loss of irriga- tion water and nutrients. The formation of the preferen- tial flow was caused by various factors, such as soil structure, tillage, worm cavity and root channeling rup- ture (Pot et al., 2005). Besides, frozen rupture can not be ignored in the northeastern China where the lowest tem- perature reaches -40℃ (Wang et al., 1993). There are several types of preferential flow, such as bypass flow, channeling flow and macro… 相似文献
12.
Moiwo Juana PAUL 《中国地理科学(英文版)》2006,(3)
1 Introduction Studying the impact of land-use on groundwater is a key issue in setting up a sound land-use planning project. Many studies have shown that land-use planning is fun- damental for the reliable protection of ecologically valuable wetlands. Thus special attention should be given to the effect of land-use on the hydrologic cycle and the protection of groundwater systems, especially recharge and discharge (Boeye and Verheyen, 1992; Bernàldez et al., 1993; Pucci and Pope, 1995; Bat… 相似文献
13.
1 INTRODUCTION It has been suggested that interior thermal anomalies that subduct into the subtropics of the North Pacific may propagate to the equatorial region of the Pacific (Russell, 1994; Deser et al., 1996; Gu and Philander, 1997; Huang and Huang an… 相似文献
14.
S.S. Samant Shreekar Pant 《山地科学学报》2006,3(1):28-47
Introduction The Indian Himalayan Region (IHR) is known for its unique, natural, representative biodiversity (Samant et al. 1998a). This biodiversity is being utilized by the inhabitants of the IHR in various forms, i.e., medicine, food (wild edibles), fuel, fodder, timber, making agricultural tools, fiber, religious and various other purposes (Samant and Dhar 1997, Samant et al. 1998b). In the remote areas of the IHR where primary health centers are located far from the villages, the in… 相似文献
15.
References： 《东北亚地学研究》2007,10(1):1-5
Conodont Caudicriodus angustus angustus(Steward et al.,1956) and Caudicriodus angustus cauda(Wang et al.,2005) were found from a big limestone lens of the Berh Hairhan Formation in the place of W 150 km to Ulaanbaatar City.The discovery indicates that the Berh Haihan Formation should be assigned to Middle Devonian Eifelian Stage.This conodont fauna was from a shallow cooler water facies in the relatively high latitude. 相似文献
16.
LI Haifeng CHI Zhenming * WANG Xiaohong and MA Chunling UNESCO Chinese Center of Marine Biotechnology Ocean University of China Qingdao P. R. China 《中国海洋大学学报(英文版)》2007,6(1):60-65
1 Introduction Amylases are enzymes which hydrolyze starch molecules to give diverse products including dextrin and pro-gressively smaller polymers composed of glucose units(Windish et al., 1965; Pandey et al., 2000; Chi et al.2001). Amylase is a kind of very important enzyme andconstitutes a class of industrial enzymes sharing approximately 25% of the enzyme market (Sindhu et al.1997; Rao et al., 1998). Amylases are universally distributed throughout the animal, plant and microbial kingdoms… 相似文献
17.
《山地科学学报》2006,(3)
Introduction Rocky desert is a distinguishing phenomenon in China’s subtropical karst region, and it is caused by serious soil erosion, large areas of bedrocks protruding above soil, or alternatively large amount of gravels piling up in the field, leading to reduction or complete loss of soil productivity. This is a form of surface soil deterioration similar to desert (WANG 2002, WANG et al. 2004). Now the rocky desert is being expanded at an astonishing speed, and now it accounts for 30 … 相似文献
18.
ZHANG Li LU Xinzhi HAN Feng MA Cuiping and YU Wengong* Marine Drug Food Institute Ocean University of China Qingdao P.R. China 《中国海洋大学学报(英文版)》2007,6(1):80-84
1 Introduction Agarases produced by agar-degrading bacteria are classified into two groups based on their modes of action, namely, α-agarase and β-agarase. They hydrolyze α -1, 3 linkage and β-1, 4 linkage of agarose respectively (Duckworth and Turvey, 1969). Agarases are widely used in food, cosmetic and medical industries for the produc-tion of oligosaccharides from agar (Kobayashi et al., 1997; Yoshizawa et al., 1995). Neoagaro-oligo- saccharides produced by β-agarase inhibit the gro… 相似文献
19.
WANGY.Y. SHANGE.C. 《青岛海洋大学学报(英文版)》2002,1(1):25-28
To assess the adiabaticity of acoustic propagation in the ocean is very important for acoustic field calculation(forward problem) and tomographic retrieving (inverse problem). A new criterion of adiabaticity is proposed recently (Shang et al., 2001). In this paper, numerical simulation has been conducted for acoustic propagation through the Polar Front to verify the new criterion. Numerical results on the f (frequency) -rn (mode number) plan demonstrate that the new criterion works very well for this extremely non-gradual ocean structure. 相似文献
20.
I INTRODUCTIONNatllral environment and water transform in theworld have changed faster and faster under the effect ofhuman activities. The study on effect of human activities to hydrological processes, and its extent and tendency has been more and more important as one of theresearch projects of hydrology in the world (RAI et al.,1998, BASS et al., 1998, WANGet al.,, 1998; HILLet al., 1998; LIU, 1997). It became one of the mainresearch program of international Hydrological Decade(… 相似文献