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1.
研究了天津开发区滨海防护圈9种植物的热值,灰分含量和元素含量以及他们之间的相关关系。结果表明:平均干重热值和去灰分热值都表现为乔木(18442.72J/g、19136.23J/g)>灌木(18138.18J/g、18701.295J/g)>多年生草本(15643.11J/g、18622.185J/g)>1年生草本(13119.33J/g、17907.91J/g)。具体数值随植物种和组分的不同而异。从植物的元素含量看,常量元素N、P、K在乔木的根、枝、皮中含量较干高;在灌木中N和P表现为根>枝,K则反之;而多年生草本地上部分和地下部分含量较接近,对于本研究区土壤主要盐分元素Na,Ca,Mg,Cl^-而言,乔木基本与常量元素N、P、K一致,仍是根、皮、枝含量高于干;灌木均为根<枝,与K一样,和N、P相反。多年生草本除大米草Ca含量外都是地上部分含量比地下部分高。植物碳含量总体上根的含量低于其他组分。植物的干重热值与碳含量呈极显著的正相关关系,与灰分含量及Na,Mg,Cl^-含量呈极显著的负相关关系,与Ca含量呈显著负相关关系,去灰分热值与碳含量和干重热值呈极显著的正相关关系。  相似文献
2.
盐碱地耐盐小麦覆膜栽培高产机理的研究   总被引:16,自引:1,他引:15  
通过测定不同NaCl浓度下不同小麦品种的发芽率(Gr)、发芽指数(Gi)和活力指数(Vi)及盐渍土壤上的产量筛选出耐盐小麦品种德抗961。研究了覆膜穴播对土壤温度、土壤含水量、土壤含盐量、产量及其构成因素、旗叶离子含量和旗叶光合作用特性的影响。结果表明,覆膜明显提高土壤温度和土壤含水量,抑制返盐。覆膜减少Na^+在旗叶中的积累,增加旗叶K^+含量。覆膜显著增加旗叶净光合速率、蒸腾速率,气孔导度和细  相似文献
3.
利用盐生植物盐地碱蓬对天津河口滨海盐碱地进行生物修复,研究了其对土壤微生物区系的影响.结果表明,种植区碱蓬根系土壤的可溶性盐分与对照土壤相比下降了41%(重量法)和37%(电导法);根系土壤的微生物数量明显增加,其中细菌、放线菌和真菌分别较对照增加了2.3倍、4.3倍和71倍,与对照相比均为显著性差异.根系微生物的耐盐性结果显示,随着土壤盐分的降低,根系微生物生长的最适盐度也随之降低,耐盐性较低的微生物种群已逐渐成为优势种群.系统发育分析表明,枯草杆菌属成为植物修复后土壤中的优势种群.  相似文献
4.
Is coordination of leaf and root growth mediated by abscisic acid? Opinion   总被引:13,自引:1,他引:12  
Leaf growth is more inhibited than root growth when the soil is nitrogen-deficient, dry, saline, compacted, or of restricted volume. Similar differential responses in leaf and root growth occur when ABA is applied to plants in well-watered and well-fertilised conditions, and opposite responses are often found in ABA-deficient mutants. ABA levels increase in plants in dry or saline soils, suggesting a regulating role in leaf and root growth in soils of low water potential. In nitrogen-deficient or compacted soils, or soils of restricted volume, ABA only sometimes increases, and in these situations its accumulation may be of secondary importance. Use of ABA-deficient mutants has so far indicated that ABA influences leaf and root growth in unstressed plants, and plants in dry soils, but not in soils that are compacted, of restricted volume, or are nitrogen-deficient.For ABA to determine the relationship between the rate of leaf growth and the rate of root growth, there must be long-distance transport of either ABA itself or a compound that controls ABA synthesis in the growing cells of leaves and roots. ABA invariably increases in xylem sap as the soil becomes dry or saline, and sometimes when it becomes nitrogen-deficient or compacted, however the ABA is of too low a concentration to affect leaf growth. There may be a compound in xylem sap that controls the synthesis of ABA in the leaf, but no such compound has been identified. ABA accumulates in phloem sap of plants in dry or saline soil, but its function in controlling root or leaf growth is unknown.We conclude that ABA affects the ratio of root growth to leaf growth via its independent effects on root and leaf growth, and may regulate the ratio of root to leaf growth via feedforward signals in xylem or phloem, but there is no satisfactory explanation of its mechanism of control.  相似文献
5.
扦插玉米秸秆改良松嫩平原次生光碱斑的研究   总被引:8,自引:0,他引:8       下载免费PDF全文
根据野外实验,提出了改良松嫩平原次生光碱斑的新方法,即通过扦插玉米秸秆截留植物种子,在玉米秸秆分解作用下,以玉米秸秆本身及其邻近区域,为植物提供生长平台,使被截留的植物种子得以顺利定居、生长;达到低成本、快速地恢复次生光碱斑植被的日的.结果表明,扦插玉米秸秆可显著提高土壤种子库,改良区土壤种子数量为4020.0±1773.6粒·m^2,次生光碱斑土壤种子库为10.0±31.6粒·m^2,被截留的种子为植被恢复提供了种源.改良区土壤理化特性得到一定改善,但仍具有高pH值、高盐分含量和低有机质含量等特征.虎尾草能在玉米秸秆周围存活,每个玉米秸秆周围可生长3.9±2.2株,产量可达68.64±38.72g·m^-2.该方法投入少、成本低、技术简单,在次生光碱斑呈斑块状、且面积相对较小的区域.具有更大的推广潜力.  相似文献
6.
采用根际袋法研究腐熟有机物料对滨海盐土水稻淹水层及土壤的盐分和植株元素吸收的影响.结果表明,在不排水条件下,施用有机物料使淹水层盐分上升,土壤盐分也高于对照,但其根际富集程度降低;植株K吸收增强,Na则明显下降,Ca、Mg含量略增,但变化没有1价元素明显.  相似文献
7.
辽北平原苏打盐渍土增施泥炭对土壤盐分的影响   总被引:6,自引:0,他引:6  
对辽河北部平原苏打盐渍化土壤改良试验表明,在增施泥炭条件下,苏打草甸盐土当年玉米产量可达2500~4400kg·hm-2,苏打碱化草甸土为5500~6800kg·hm-2,增产率分别为40~144%和127~181%;第2年后者的持续产量为6200~8000kg·hm-2,增产率仍高达69~118%.相应地,土壤剖面特别是耕作层呈现为明显脱盐,pH及碱化度下降,土壤有机质、全氮及全磷含量增加.  相似文献
8.
东北地区内陆苏打盐渍土旱作玉米实施泥炭改良的研究   总被引:5,自引:1,他引:4  
东北地区内陆苏打盐渍土旱作玉米实施泥炭改良的研究金凤鹤西崎泰山口达明尹怀宁白鸿祥郑应顺(千叶工业大学工学部,日本)(辽宁师范大学地理系,大连116029)StudyofApplyingPeatAmeliorationinSoda_SolonchakC...  相似文献
9.
Soil conditions of mangrove forests in southern Japan were found to correlate largely with zonal distributions of the species.Kandelia candel grew in soils with low salinity and low pH,Avicennia marina, Rhizophora stylosa andSonneratia alba in soils with high salinity and high pH, andBruguiera gymnorrhiza in soil with a wide range of pH but limited range of salinity.Lumnitzera racemosa colonized soil with a wide range of pH and medium salinity. Seedlings ofKandelia candel, Bruguiera gymnorrhiza andRhizophora stylosa were planted in soils with differing salinity and pH. Optimum seedling growth ofKandelia, Bruguiera andRhizophora occurred when plants were cultivated in soils similar to those of their natural habitats, suggesting that growth of mangrove species and their zonal distributions were regulated by salinity and soil pH.  相似文献
10.
Desert perennials as plant and soil indicators in Eastern Arabia   总被引:4,自引:0,他引:4  
Soils of different Eastern Arabian vegetation types, dominated by five desert perennials have been analysed for their texture, salinity and surface hardness. The vegetation types were analysed for plant species richness and composition. Special emphasis was given to Abu Dhabi's widespread terrestrial perennials Cyperus conglomeratus Rottb., Haloxylon salicornicum (Moq.) Bge., Pennisetum divisum (Gmel.) Henr., Seidlitzia rosmarinus Ehrenb. ex Bge. and Zygophyllum mandavillei Hadidi. The results show some important relationships between soils and plants. C. conglomeratus indicates the lowest soil salinity levels and the finest texture. P. divisum indicates the highest species richness and S. rosmarinus indicates the lowest species richness. Z. mandavillei indicates the highest salinity levels, the largest soil particle size, and the hardest soil surfaces.  相似文献
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