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本文通过野外定位观测,对晋西黄土高原三趾马红土(N_2)的泻溜侵蚀规律进行了初步研究。研究表明:泻溜侵蚀是红土一种物理风化和搬移过程,其侵蚀作用一年四季都有发生,侵蚀强度干季大于湿李,高峰期多出现在冻融频繁的3～4月份;产生泻溜的地表坡度在40°～60°之间,每平方米泻溜面积上全年泻溜总量可达40～50kg;地面坡度、土壤含水量、冻融和风力等因素与泻溜侵蚀强度均有密切的关系。 相似文献
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<正> 泻溜侵蚀,是指黄土区出露的红土因热力、冻融等物理过程而产生的碎屑在重力作用下沿坡面滚动、滑溜的现象。在红色土出露广泛的地区,它是一种重要而强烈的侵蚀产沙方式。海东黄土区(青海东部黄土丘陵区)位于黄土高原与青藏高原的过渡地带,拉脊山和达板山横贯区内,将其分为大通河、湟水和黄河干流谷地三大流域,山体海拔多在4000m以上、生物、气候要素具有明显的垂直分异,广大低山丘陵区红色土广泛出露,泻溜侵蚀强烈。 相似文献
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泻溜侵蚀是黄土高原一种严重的土壤侵蚀方式,它是高含粘量地层因粘土矿物的强烈吸水膨胀而引起的地质现象。在一个流域里,泻溜面的分布数量和规模,随侵蚀沟不同发育阶段内在侵蚀力的变化而变化,主要发生于中游以上地区,愈向下游分布愈少。支沟中泻溜的分布状况与主沟分布状况十分相似。河谷阶段的沟谷,泻溜分布于河谷阶地下红层露头处和沿新谷坡发育起来的短小切沟中,切沟阶段沟谷的泻溜面沿沟床两侧条状分布。防治泻溜侵蚀,最关键的是要稳定坡脚和沟床。只有当泻积物在坡面堆积创造了条件后再在泻溜面上种草、造林,才会收到好的治理效果。 相似文献
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“红土”陡坡的泻溜侵蚀及其防治 总被引：1，自引：0，他引：1
为了进一步探索黄土高原沟壑区“红土”泻溜的规律及其治理措施,我们曾在甘肃省西峰镇南小河沟布置了定位试验。此外还对甘肃子午岭林区及晋西部分地区作了些调查研究工作,所得结果分述如下。 相似文献
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渭源县里仁沟流域红土裸露面积占流域总面积的６０．６％，水蚀和红土泻溜等重力侵蚀严重。在治理中，突出综合作用，坚持工程措施和植物措施相结合，拦蓄利用梁坡径流稳定坡脚和沟床，雨季红土坡穴播沙棘、沙打旺等林草。经过五年连续治理，全流域累计完成基本农田６２８．７７ｈｍ￣２，造林５６２．６ｈｍ２，种草１５０．０７ｈｍ￣２，治理水土流失面积１３．４１ｋｍ￣２，其中红土治理面积６．２７ｋｍ￣２。土地利用和产业结构得到初步调整，人均收入由治理前的２０６．５１元增加到４０７．０９元，林草覆盖率由６．１％上升到４０．６％，年径流模数由３１２３８．６ｍ３／ｋｍ￣２降低到１１９２８．４ｍ３／ｋｍ￣２，年土壤侵蚀模数由５６００ｔ／ｋｍ￣２降低到１１６５．９ｔ／ｋｍ￣２。 相似文献
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米脂县黄土滑塌分布及其对流域产沙的影响 总被引：1，自引：0，他引：1
<正> 土壤重力侵蚀在黄土高原流域产沙中占有很大比重。黄土重力侵蚀主要有滑坡、滑塌、泻溜和崩塌四种方式,其中以滑坡发生规模最大,分布也比较普遍。但是,滑坡并不是经常发生的,而且,由于滑坡产生后土体地貌条件由不稳定变得相对稳定,反而对流域产沙产生抑制作用。因此,如果将重力侵蚀看作影响黄土高原流域产沙的重要因素,那么主要指的应该是黄土滑塌、泻溜和崩塌。本文利用遥感方 相似文献
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贵州老万场红土型金矿属是一种喀斯特崩塌堆积型金矿,经长期的破坏性开矿活动,使得大量石灰岩出露于地表,并形成了新型的石漠.在这样的干燥地区,苔藓植物已经成为主要的土壤结皮植被类群.为了探索红土型金矿区苔藓植物土壤结皮特征,2007年8月对贵州晴隆老万场红土型金矿石灰岩和红土矿体表面苔藓植物进行了研究.通过野外全面调查和实验室仔细鉴定,发现老万场红土型金矿石灰岩和红土矿体表面共有苔藓植物10科23属35种,没有发现苔类植物;石灰岩上有5科11属16种,红土型金矿上有5科20属26种,这两个区域有6个相同的属,7个相同的种;丛藓科种类是石灰岩和红土矿体表面上主要的土壤结皮藓类植物,石灰岩和红土矿体表面的土壤结皮藓类植物的属种相似性都比较低;石灰岩土壤结皮藓类群落都为纯群落,红土矿体表面多为混生群落. 相似文献
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环洞庭湖区两种典型红土理化特性比较研究 总被引：1，自引：0，他引：1
通过环洞庭湖区两种典型成因红土的野外勘察与取样、室内磁化率、粒度、微量元素(Li、Rb、Sr、Ba)分析,进行两种不同成因的红土理化性质的比较。研究结果表明,风成成因的红土粒度比基岩风化成因红土明显较细,风成成因红土以粉砂为主,基岩风化型红土为砂和粉砂为主;两种成因红土受到长江中游地区高温高湿的气候条件影响,磁化率均显示为低值,明显低于黄土高原黄土和长江下游下蜀黄土;微量元素Li/Ba、Rb/Sr比值显示为高值,显著高于黄土高原黄土和长江中下游地区下蜀黄土,表明两种红土均经历了强烈的风化淋溶过程,但基岩风化型红土的风化成壤强于风成成因红土,可能基岩风化型红土经历了更长的风化成壤过程。 相似文献
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Suyundukov Ya. T. Suyundukova M. B. Bezuglova O. S. Khabirov I. K. Khasanova R. F. Semenova I. N. Rafikova Yu. S. Ilbulova G. R. 《Eurasian Soil Science》2022,55(1):27-35
Eurasian Soil Science - The results of the study of the properties of urban soils of the city of Sibay located in the mining region of the Republic of Bashkortostan are presented. A specific... 相似文献
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Kholodov V. A. Farkhodov Y. R. Yaroslavtseva N. V. Ziganshina A. R. Maksimovich S. V. 《Eurasian Soil Science》2022,55(7):998-1004
Eurasian Soil Science - Layers were step-by-step removed from macroaggregates (2–1 mm in diameter) of Protocalcic Chernozems via successive abrasion in a revolving rotator during 5, 10, 15,... 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(15-16):1631-1646
Abstract Brazil has approximately 30 million hectares of lowland areas, known locally as “Varzea,”; distributed throughout the country. Soils in these areas have the potential to support agricultural production, but very little is known about their fertility. The current experiment was undertaken to characterize the chemical and physical properties of representative “Varzea”; soils collected at 0–20, 20–40, 40–60, and 60–80 cm depth intervals from 23 sites in Goias State of Brazil. Organic matter contents averaged 42 g/kg in the surface 20 cm of soil and should make a significant contribution to overall nutrient availability. Soil pH increased slightly with depth from a mean value of 5.2 in the surface 20 cm of soil to a mean value of 5.4 in the 60–80 cm depth interval. Several soils had exchangeable Al values ≥ 1.0 cmol Al/kg, but soil Al saturation was generally less than the 60% level frequently associated with Al toxicity. However, cereal and legume production could benefit from lime addition in many of these soils. Although base saturation was fairly low in some soils, exchangeable Ca and Mg levels were, in general, adequate throughout the profile. Extractable P levels were adequate in most surface soil samples. Extractable K levels in these soils were generally low, and the application of K fertilizers should be beneficial, especially in conjunction with lime addition. The high clay content “Varzea”; soils of the Brazilian lowlands have some drainage problems but generally exhibit favorable chemical properties for crop production when compared to soils of the well‐drained Cerrados. 相似文献
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Ye. V. Rogozhina N. V. Kostina L. S. Malyukova 《Moscow University Soil Science Bulletin》2011,66(1):32-35
An estimation of potential nitrogen-fixing activity of various soil types under agrophytocenoses of tea, filbert, peach, and
pawpaw which grow in the area of Greater Sochi is given. High indicators of nitrogen fixation activity in the soil in the
course of vegetation were characteristic of agrocenoses of pawpaw, peach, and filbert. The lowest level of nitrogen fixation
was noted in the soil of a tea plantation. A negative correlation dependence of potential nitrogen-fixing activity on the
acidity of the soil solution was established. A study of the seasonal dynamics of the activity of nitrogen fixation of soils
of agrocenoses of the subtropical zone of Russia made it possible to distinguish a less active winter and more active spring-summer-autumn
periods. 相似文献
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The rate of popping of popcorn was measured in oil and in air. Kinetic data for lifetimes of individual kernels from a large population were obtained in oil at six constant temperatures (180–250°C) and also in an air‐popper at 202°C. The data are characterized by an induction period, which is, significantly, followed by a first‐order decrease in the number of unpopped kernels versus time. The activation energy for the first order process is 166.7 kJ/mol between 180 and 210°C, and 53.8 kJ/mol between 210 and 250°C. These data are consistent with a model that assumes 1) that the rate of heat transfer into a kernel follows Newton's law of cooling; 2) that in a sample of kernels there exists a distribution of critical pressures; 3) that for an individual kernel, the probability of popping is directly proportional to the difference between the internal aqueous vapor pressure and the kernel's critical pressure; and 4) that the measured rate constant at any temperature is an average overall of the kernels in the sample with critical pressures equal to or less than the internal aqueous vapor pressure. Minimum popping temperatures predicted by the model are 181 ± 2°C (oil) and 187 ± 2°C (air), in good agreement with previously reported direct measurements. 相似文献
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物联网是一个集信息通信、数据交换、传感器技术与软件工程于一体的综合性产业,探讨和分析了物联网的结构体系与发展中遇到的安全问题。 相似文献
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荔枝种子从果实中剥离出来后, 即使在室内条件下, 也极易失水干缩, 潮湿环境中又易发霉而腐烂。扫描电镜观察表明: 种皮上布满纹孔, 水分散失面积很大; 种脐部为疏松的海绵组织, 且营养丰富。据此, 生产上应对种子彻底清洗, 并保存于适当湿度的环境中, 以提高其发芽率。 相似文献