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11.
受抗战大后方垦殖督导活动带动,以粮食、纤维、油料等农作物和经济作物品种改良、各级农技培养与服务体系建设为主的贵州省农业技术推广运动,在1938年前后开始得到积极实施,掀起了黔省自清代中期移民开发以来的农业发展又一高潮。尽管新一轮的农业开发历时较短,但当时贵州省稻、麦等农业作物和棉花、桐油等经济作物品种得到较大规模的改良、引进及推广,在20世纪40年代中期显现出良好经济效益,同时也对地区社会和生态等产生了深刻影响。本文就此做出梳理,并进一步分析和探讨此轮物种变化带来的贵州地区农业经济和生态区域变化及其特征。  相似文献   
12.
This paper presents the results obtained from field spectroradiometric campaigns over Neolithic tells (“magoules”) located at the Thessalian region in Greece. In each one of the four archaeological sites selected, three sections were carried out using the GER 1500 handheld spectroradiometer. Spectral profiles of the sections and several vegetation indices such as Normalized Difference Vegetation Indices (NDVI) and Simple Ratio (SR) have been examined in this study. This is one of the first times that ground hyperspectral data are evaluated in such context of archaeological research for the spectral characterization of archaeological features. As it was found, ground spectroradiometric measurements can be efficiently used in order to support and validate satellite imagery results for the detection of archaeological sites.  相似文献   
13.
The capability of satellite QuickBird imagery for the identification of archaeological crop marks is herein presented and discussed for two test sites located in the South of Italy. The selected sites, dating back to Middle Ages, were buried under surfaces covered by herbaceous plants characterized by a different phenological status (dry/green) when the satellite data were acquired.  相似文献   
14.
This paper explores the impact of animal manure application on the δ15N values of a broad range of crops (cereals and pulses), under a range of manuring levels/regimes and at a series of locations extending from northwest Europe to the eastern Mediterranean. We included both agricultural field experiments and areas where ‘traditional’ farming is practised. Our aim is to ground-truth interpretation of δ15N values in archaeobotanical crop remains as evidence of past growing conditions and husbandry practices. The results confirm the potentially radical impact of manuring on δ15N values in cereals, depending on manuring level, but indicate only a slight effect on pulses, which can fix atmospheric nitrogen. The expected geographical trend towards greater δ15N with increasing climatic aridity is not apparent, probably because the growing conditions for crops are ‘buffered’ through crop management. Each of these observations has fundamental implications for archaeobotanical interpretation of δ15N values as evidence of land use practices and (together with analysis of bone collagen/tooth enamel in potential consumers) palaeodiet.  相似文献   
15.
Archaeobotany, ethnographic observation, and laboratory experimentation are brought together to build model sequences of grape processing parallel to the better studied and reported sequences in existence for cereal processing. A set of such model sequences is developed and presented, and explored in the context of rich archaeobotanical assemblages from the Hellenistic farmstead at Komboloi in Southern Macedonia. We conclude that the remains of pressed grapes are reasonably distinctive, whereas whole grapes and raisins can leave similar material in charred state, requiring close scrutiny for secure separation. Our model sequences are further considered in the light of other sites in which Vitis remains have been variously interpreted, and our own reinterpretations offered.  相似文献   
16.
Archaeobotanical research over the past decades has revealed that bread wheat of a compact form, called “Ezo wheat” in Japan, was present in the Far East Asian region (Primorye in the Russian Far East, the Korean peninsula, and the Japanese archipelago) during the early stage of wheat cultivation. In response to the previous observations, carbonized wheat grains from the sites in the southern part of the Korean peninsula were measured and their sizes were compared across these sites and with other sites in East Asia. The examination indicates that grains dated over the period of AD 100–600 were considerably smaller than the modern specimens but were plumper than the previously reported Ezo wheat. The new data sets suggest that wheat with plumper kernels was introduced to the region no later than the Three-Kingdoms period (ca. AD 300–668) and continued to be cultivated until the Joseon period (1392–1910).  相似文献   
17.
本文提出了玉米、番薯集中产区和一般产区的数量标准,探讨了清代至民国时期山东东部地区玉米、番薯的分布特征,阐明了玉米、番薯以竞争的方式取得优势地位的过程,以及南方和北方的玉米、番薯不同的发展模式。研究表明,与南方的玉米、番薯发展模式不同,在北方,两种美洲作物以竞争的方式排挤了原有作物,并导致作物结构由多样性渐趋向于简单化。  相似文献   
18.
Even though the sun has its peak emission of electromagnetic (EM) radiation in the visible waveband, it still produces a substantial amount of ultraviolet (UV) wavelengths (10–400 nm). However, the largest portion of this emitted energy is blocked by the ozone layer of the atmosphere, only allowing the near-ultraviolet or NUV (comprising the spectral band between 315 nm and 400 nm) to reach the earth's surface. Additionally, sensors acquiring this part of the UV wavelengths must be operated from low altitudes to minimize the effects of strong Rayleigh scattering to which the NUV radiation is subjected. Consequently, this waveband of the EM spectrum is rarely employed in aerial photography and its reflected portion only acquired in very specific applications.  相似文献   
19.
Recent archaeological studies of human diet have used stable nitrogen isotope ratios (δ15N) from human bone collagen to infer the relative importance of terrestrial plant and animal foods. This approach is based on widely observed enrichment of δ15N up the food chain, plants having distinctly lower values than the herbivores that consume them. Studies of early farming diets in Britain, Denmark and Germany have tended to detect relatively high δ15N values (e.g. c. +9‰), interpreted as evidence of a diet largely based on animal products, though archaeobotanical evidence for crop cultivation (e.g. carbonised cereal grain and chaff) is widespread. This paper investigates the impact of manuring on δ15N values in modern cereals, and of charring on these cereal values. The results from two long-term experiments demonstrate that manuring significantly raises δ15N in cereal grain and chaff. Depending on manuring levels and frequency, it appears that human diets with a major component of such grain would conventionally be interpreted as indicating a largely animal-based diet or a mixed plant/animal diet. Moreover, preliminary analyses of experimentally charred grain and chaff from manured and unmanured conditions are promising for the extraction of reliable ancient δ15N values from archaeobotanical cereal remains. The wider implications of these results, and the need for further work, are discussed.  相似文献   
20.
汉代黄河流域麦作发展的环境因素与技术影响   总被引:1,自引:0,他引:1  
汉代冬小麦的推广与普及,具有自东向西的时空特点。麦作发展是区域自然环境与技术条件交互作用的结果,其中自然环境条件是影响汉代黄河流域冬麦普及过程的基本因素。不论是黄河下游地区冬麦种植的较早普及还是关中地区冬麦推广的迟滞,均首先与当地的自然环境有关。在黄河下游地区,人们利用冬麦的生长特性趋利避害,减少和防止河汛水患的影响,保障粮食生产,麦子得以广泛种植。在关中地区,干旱的困扰一度制约了冬麦的推广和普及。在自然因素推动下的汉代麦作推广与普及,促进了黄河流域抗旱耕作及粮食加工技术的发展,影响深远。  相似文献   
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