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721.
Zonal distribution of the erosion-landslide and soil micromorphological features in purple hilly region 总被引:3,自引:0,他引:3
HEYurong LIAOChaolin XUPei ZHANGBaohua 《山地科学学报》2005,2(1):42-49
In the purple hilly region, erosions and landslides are all serious, and it is of great scientific value and practical significance to study their formation mechanism and distribution features there.In this paper, soil micromorphological methods and techniques were used to study the erosion zonal distribution in the region. The results indicated: (1)According to erosion process, the spacial distribution zones of the erosions and landslides in the purple hilly region with different solums were divided into scouring erosion zone, transport-diffusion zone, rocks and soil turbulence zone and sediment-bury zone; (2) The soil micromorphologic taxonomic feature identifying different erosion-landslide zone were found by studying the soil micromorphology of erosive zone in purple hilly region; (3) As for the erosion-landslide formation in the region, besides the external factors, the internal factors were found more important and favorable for landslide formation through the studies on the micormorphologieal features of slide soil. 相似文献
722.
New technologies and systems for high quality citrus fruit production,labor-saving and orchard construction in mountain areas of Japan 总被引:3,自引:1,他引:3
KunihisaMORINAG~ OsamuSUMIKAWA OsamuKAWAMOTO HiroyasuYOSHIKAWA SeijiNAKAO MasahikoSHIMAZAKI Shin-no-sukeKUSABA NorihiroHOSHI 《山地科学学报》2005,2(1):59-67
Novel technologies have been necessary for improving fruit quality and productivity of citrus,labor-saving and orchard conservation on steep slope lands since aging of growers and decrease in the number of successors is remarkable in mountain areas of southwestern Japan. The purpose of this paper is to introduce new technologies for improving citrus production that have been developed in recent years. A new fruit quality control system using drip irrigation and liquid fertilization technique combined with year-round plastic mulching was developed, and it enables high quality and stable citrus fruit production. Water and/or nutrient solution is automatically supplied through drip tubes that are laid under the mulching sheets to give adequate water stress, so as to improve sugar and acid content of fruit. A new transportation system for steep sloping citrus orchards, which is a combination of the monorail system and contour narrow paths, was suggested. A small walking cultivator was developed to explain the procedure of narrow path excavation. After introducing the narrow path, working hours for fertilizer and chemicalherbicide application were reduced. Disasterpr evention mapping of citrus orchards on slope landswas developed based on computer-aided seepage estimation and topographic data. The mapping can show zones of both ascending flow and descendingflow of underground water during heavy rains incitrus orchards. The mapping is considered to be effective for the management of orchards andprevention of erosion on slope lands. 相似文献
723.
VishwambharPrasadSati 《山地科学学报》2005,2(1):76-85
Agricultural practices are the main stay of the people of Uttranchal. Out of the total population,more than 75% people are engaged either with the main occupation of agriculture or its allied practices,dominated by traditional subsistence cereal farming.Among them, the main crops are rice, wheat, millet,barley, all types of pulses, all types of oilseeds and almost all types of fruits. The crops, vegetables and fruits of all varieties are grown in the different climatic zones such as tropical, temperate, and cold because, the region is characterized by the different altitudinal zones elevated from 200 m to more than 8000m. As a result, different climates are found from hot tropical to sub temperate and chilly cold. Pulses varieties are grown extensively. Among vegetables,potato, onion, carrot, all types of green leaf vegetables,brinzal, pumpkin, ladyfinger, pea, gram, radish,ginger, garlic, etc, are grown widely. All fruit varieties are grown in the different altitudinal zones. The mainfruits are orange, malta (a big size of orange),elephant citrus, lemon and all other types of citrus,apple, stone fruits including peach and pears, manykinds of nuts, and the fruits which are grown in the low lying areas. In spite of feasible climatic conditions,agricultural dominant society, and availability of all types of crops, the production and productivity of these crops are very low, even they are unable to meet the grain-need of the people in Uttaranchal. Agricultural crops are grown almost in all the altitudinal zones -- from the low-lying areas, which are called ‘Ga. ngarh‘, to the highly elevated region,where the legendary term is given as ‘Danda‘. The growing seasons vary according to the heights. The present paper aims to discuss the agricultural practices including cropping season, cropping pattern,land use, production of cropsagricultural system in thisand ecological aspect of Himalayan state and suggest some measures for developing farming system,which could lead the sustainability, in terms of meeting the food grain needs of the people on the one hand and restoring the ecological balance on the other. 相似文献
724.
RENLi-jun SHANGJin-cheng 《中国地理科学(英文版)》2005,15(1):42-46
1INTRODUCTIONFor recent years, many countries have increasingly paidattention to the research on strategic environmental as-sessment (SEA) and taken it as one of key supportingtools for pursing sustainable development (BROWNand THERIVEL, 2000; PRARTIDARIO… 相似文献
725.
MO Jia-qi LIN Yi-hua WANG Hui 《中国地理科学(英文版)》2005,15(3):227-230
1IN T R O D U C T IO NInteractionsbetween the ocean and atmosphere con-tributeto climatefluctuationosver a broad spectrum oftime scales.Studiesof those interactionhsave farfo-cused on El Ni o-SouthernOscillation(ENSO)phe-nomenon thathas a period of3to4yea… 相似文献
726.
WANG Nai-ang ZHANG Chun-hui LI Gang CHENG Hong-yi 《中国地理科学(英文版)》2005,15(3):245-253
1IN TR O D U CTIO NH istoricdaelsertificatiisonnotonlythekeyissueon theinteractiobnetweennatureandhuman proces,sbutalsothemost challenginigssueinthecomplex reltaionshipbetweenhuman andland.Previousl,ymostChinesesci-entistisnthisfieldcarrieoduttheiresearch… 相似文献
727.
MAO Duan-qian ZHANG Jie BAO Hao-sheng 《中国地理科学(英文版)》2005,15(3):275-280
1IN T R O D U C T IO NAn image isa setofbelief,s ideasand impressionsthatapersonholdsaboutan object(KOTLER,1991).Similar-lydefinitionistheimage of a destinationas thesum ofbelief,sideasand impressionsthatpeoplehave ofa placeor destination(CROMPTON,1979;KO… 相似文献
728.
SORPTION AND DESORPTION CHARACTERISTICS OF CADMIUM BY FOUR DIFFERENT SOILS IN NORTHEAST CHINA 总被引:3,自引:0,他引:3
ZHANG Lei SONG Feng-bin 《中国地理科学(英文版)》2005,15(4):343-347
1IN TR O D U C TIO NA s a persistentand toxic pollutant, cadm ium (C d) canresultin m any adverse health effects in a variety oftis-suesand organssuch asthe lung,kidney,urinary,blad-der,pancreas,breast and prostate (SA TA R U G etal.,2003).C adm ium in so… 相似文献
729.
WU Quan-yuan AN Guo-qiang BAO Wen-dong ZHANG Zu-lu XU Qiu-xiao FANG Xue-mi 《中国地理科学(英文版)》2005,15(4):355-360
1 IN T R O D U C T IO NZhaoyuan C ity, located in northeast of ShandongProvince,iscalled "G old C ity"and itisone ofim portantgold production bases in C hina.The exploitation ofthegold broughtoutthe extensive vacantareas,leading tolarge-scale ground subsi… 相似文献
730.
HUANGGuoqiang DONGShuanglin WANGFang 《中国海洋大学学报(英文版)》2005,4(1):56-60
Attractabilities of different diets and dietary selectivity of Chinese shrimp, Fenneropenaeus chinensis were studied through behavior observation and feeding experiment, respectively. The five diets used in the experiment are: Fish Flesh (FF), Shrimp Flesh (SF), Clam Foot (CF), Polychaete Worm (PW), and Formulated Diet (FD). No significant differences of attractability exist between any two different diets when every two natural diets or all five diets are provided simultaneously. On the other hand, significant differences of attractability exist between FD and every single natural diet when they are provided simultaneously. Results of behavioral observation indicate that natural diets are more attractive than FD. In feeding experiment, Chinese shrimp has distinct selectivity on different diets. It positively selects CF and PW, negatively selects FF and SF, and excludes FD absolutely. The results of the present studies indicate that the dietary selectivity of shrimp was based not only on the attractabilities of the diets, but also on the responses such as growth and food conversion. 相似文献