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51.
This study was performed under greenhouse conditions, with coir dust, moss peat, and sedge peat as the main components of the growing media. The performance of the media was evaluated through the growth of the primula (Primula obconica) plant. In general, aeration capacities were found to be relatively low, except for growing media that included moss peat mixtures. Nevertheless, easily available water content of all growing media was found to be within the appropriate ranges. Total and water-available plant nutrient contents of coir dust, moss peat, and sedge peat significantly fluctuated. Ornamental parameters related to media treatments were statistically significant, with respect to visual score performances, total leaf numbers, crown width, and total plant fresh weights. This study determined that coir dust, which is an industrial by-product, could be utilized for up to 50% of the total composition of coir dust-moss peat based media in floricultural aims. As floricultural quality parameters considered, 50% coir dust and 50% moss peat and 25% coir dust and 75% moss peat gave good results as much as 100% moss peat.  相似文献   
52.
Scopelophila ligulata (Spruce) Spruce, S. cataractae (Mitt.) Broth., and Mielichhoferia japonica Besch. (Mielichhoferia mielichhoferi (Hook.) Wijk et Marg. var. japonica (Besch.) Wijk et Marg.) are well known “copper mossess” which show peculiar ecological characteristics consisting of a preference for metal-rich soils, lithosols, rocks, etc. as their substrates. The total and water-soluble element contents in the substrates and heavy metal contents in the moss body were analyzed in this study. The results of these chemical analyses were as follows: The iron contents in the moss body and substrate of S. ligulata were higher than those of S. cataractae and M. japonica. On the contrary the copper contents of the former were lower than those of the latter. The pH values of substrate of S. ligulata were lower than those of S. cataractae and M. japonica. The concentrations of water-soluble iron and sulfate in the substrate of S. ligulata were higher than those of S. cataractae and M. japonica. On the contrary, the water-soluble copper concentrations in the substrate of S. ligulata were lower than those of the others. Although in the substrate of S. cataractae the iron content was several times higher than the copper content, in the moss body the copper content was higher than iron content.  相似文献   
53.
Extract of soil under colonies of Hypnum plumaeforme inhibited the growth of roots and shoots of cress, lettuce, lucerne, ryegrass, timothy, Digitaria sanguinalis and Echinochloa crus-galli . Increasing the extract concentration increased the inhibition, which suggest that the soil may contain growth inhibitory substances and possess allelopathic potential. The extract of the soil under H. plumaeforme was purified and two main inhibitory substances were isolated and determined by MS and 1H- and 13C-NMR spectral data as momilactone A and B. Momilactone A and B inhibited hypocotyls and roots of cress seedlings at concentrations >10 and 1 μ m respectively. The endogenous concentration of momilactone A and B in H. plumaeforme was 58.7 and 23.4 μg g−1 dry weight respectively and the concentration of momilactone A and B in MS growth medium of H. plumaeforme was 4.3 and 6.4 μg g−1 dry weight of H. plumaeforme , respectively. These results suggest that momilactone A and B were probably secreted into the medium during the incubation and momilactone A and B found in the soil under H. plumaeforme may have been released by the moss. Therefore, growth inhibitory activity of the soil under H. plumaeforme may be caused by momilactone A and B, which may act as allelopathic agents of H. plumaeforme .  相似文献   
54.
为能了解5种藓类在系统演化上的地位,通过扫描电镜观察了小仙鹤藓(Atrichum crispulum)、赤茎小锦藓[Brotherella erythrocaulis]、悬垂青藓(Brachythecium pendulum)、丛生木灵藓(Orthotrichum consobrium)、纤枝细羽藓(Cyrto-hypnum bonianum)等5种藓类孢子的形态.结果表明,这5种孢子的形状、大小及外壁纹饰的区别显示了不同种之间的遗传分化及系统演化.  相似文献   
55.
苔藓泥炭对高含沙土壤水动力学参数的影响   总被引:1,自引:0,他引:1  
从水动力学角度探讨了苔藓泥炭对高含沙(沙土比7∶3)土壤水分运动的影响。结果表明:随着苔藓泥炭含量增加,土壤饱和含水量、毛管含水量和田间持水量均线性增加;土壤持水曲线逐渐上移,持水性和供水能力明显增加,当吸力增加到0.5×105Pa时,各处理土壤的比水容量均出现10-2数级;原状土饱和导水率随泥炭含量增加呈先增后降的变化趋势,在30 g/kg达到最大值,而压实后的饱和导水率呈逐渐下降趋势。  相似文献   
56.
[目的]研究芽孢杆菌与植物生长调节剂对苔藓结皮生长发育的影响,为提高苔藓结皮种源扩繁效率提供科学依据。[方法]选择芽孢杆菌(胶质芽孢杆菌/巨大芽孢杆菌)与生长调节剂(噻苯隆)2种因素,设计双因素完全试验,观测温室条件下苔藓结皮的覆盖度、株高度和株密度。[结果]①只添加胶质芽孢杆菌处理的苔藓生长状况最优,相比对照组(未添加芽孢杆菌及生长调节剂)分别提高了苔藓覆盖度(+18.9%)、株高度(+0.85 mm)和株密度(+15.44株/cm~2);②添加巨大芽孢杆菌能提高苔藓株密度(+5.76株/cm~2),但会减小其株高度(-0.78 mm),对盖度则无显著影响;③生长调节剂TDZ减小了苔藓植物覆盖度(-11.78%)、株高度(-3.33 mm),对株密度影响不显著;④芽孢杆菌与生长调节剂存在交互作用,巨大芽孢杆菌+TDZ处理增大了苔藓株密度(+9.79株/cm~2),且高于只添加巨大芽孢杆菌处理(+3.67株/cm~2),胶质芽孢杆菌+TDZ处理增加苔藓株密度(+4.3株/cm~2)但弱化了胶质芽孢杆菌的促进作用(-11.14株/cm~2)。[结论]功能性微生物与生长调节剂对苔藓结皮生长发育具有显著影响,在今后苔藓结皮种源扩繁实践中应加以考虑和借鉴。  相似文献   
57.
陕北黄土高原藓结皮的7种土壤酶活性及其剖面分布特征   总被引:1,自引:0,他引:1  
【目的】研究藓结皮对土壤酶活性及其剖面分布特征的影响,为认识和理解生物结皮的生态功能提供实证,同时也为黄土高原生态修复提供参考。【方法】以陕北黄土高原的藓结皮为对象,测定了0~12cm土层藓结皮和无结皮处理土壤的7种酶(脲酶、碱性磷酸酶、蔗糖酶、蛋白酶、过氧化氢酶、过氧化物酶、多酚氧化酶)活性,分析藓结皮和无结皮处理土壤养分含量、酶活性及其剖面分布特征的变化,并分析藓结皮和无结皮条件下不同土壤酶活性的相关性。【结果】在0~12cm土层,藓结皮处理的全氮、全磷、碱解氮、速效磷以及土壤有机质含量均高于无结皮处理,藓结皮处理的5种土壤养分含量的平均值分别是无结皮处理的0.53,0.29,0.34,0.81和0.24倍。藓结皮处理极显著提高了表层(0~2cm)土壤7种酶的活性,其脲酶、碱性磷酸酶、蔗糖酶、蛋白酶、氧化氢酶、过氧化物酶和多酚氧化酶活性分别是无结皮处理的3.51,44.76,32.91,2.22,2.47,9.93和4.13倍;显著提高了2~6cm土层碱性磷酸酶、蔗糖酶以及蛋白酶的活性,3种酶活性分别是无结皮处理的9.41,9.28以及1.78倍;极显著提高了0~12cm土层过氧化物酶和多酚氧化酶活性,2种酶的活性分别是无结皮处理的18.58和8.69倍。藓结皮与无结皮条件下,土壤酶活性具有类似的剖面分布规律,均随土壤深度的增加总体呈递减趋势,但藓结皮条件下土壤酶活性的剖面表聚特征更为明显,无结皮条件下的表层(0~2cm)土壤酶活性为下层(10~12cm)土壤的1.97~12.97倍,而藓结皮条件下的表层土壤酶活性为下层土壤的0.76~6.53倍。藓结皮条件下7种土壤酶活性之间呈极显著相关性,而无结皮条件下7种土壤酶活性的相关性相对较差。【结论】藓结皮对土壤养分积累和酶活性具有促进作用,对土壤肥力提升、退化土地治理以及生态环境修复均有重要意义。  相似文献   
58.
为了筛选白发藓繁殖的适宜台垫和基质,提高白发藓人工繁殖率和质量,将白发藓分别在5种苔垫(苔纤布、毛毡布、无纺布、海绵、三维苔纤布)和6种基质(陶粒、鹿沼土、蛭石、植金石、赤玉土、珍珠岩)上断茎繁殖120 d,考察白发藓的生物量、颜色评分、叶绿素含量和覆盖度4个指标。结果表明:白发藓在苔纤布上生物量为2064 g/m2,颜色评分为4.33分,叶绿素含量为2.16 mg/L,覆盖度为50.33%;在赤玉土上生物量为9072 g/m2,颜色评分为8分,叶绿素含量为3.15 mg/L,覆盖度为83.31%,白发藓生长适宜的苔垫和基质分别为苔纤布和赤玉土。  相似文献   
59.
黄土高原不同发育阶段生物结皮的导水和持水特征   总被引:1,自引:0,他引:1  
为探明黄土高原不同发育阶段生物结皮对土壤导水和持水特性的影响,以裸沙和不同发育阶段生物结皮(藻结皮、藻-藓混生结皮、藓结皮)为研究对象, 分别采用定水头法和威尔科克斯法对其导水和持水特性进行了测定。结果表明, 在0~10 cm土层, 生物结皮显著降低了土壤饱和导水率, 藻结皮、藻-藓混生结皮和藓结皮土壤的饱和导水率较裸沙分别平均下降了59.3%,62.9%和27.6%;同时, 其水分入渗参数(初始入渗速率、稳定入渗速率、平均入渗速率和累积入渗量)较裸沙分别平均降低了37.7%、54.3%和18.4%, 延缓了土壤水分入渗过程;此外, 3种发育阶段生物结皮的田间持水量(体积含水量)较裸沙分别增加了0.97、1.10和0.70倍, 退水过程(0~120 h)的平均土壤体积含水量分别增加了1.14、1.40和0.74倍。与裸沙相比, 不同发育阶段的生物结皮均显著降低了土壤导水率, 同时提高了土壤持水性;其中藻-藓混生结皮对土壤导水和持水性能的影响大于藻结皮和藓结皮, 其主要原因可能是不同发育阶段生物结皮中非维管束植物和微生物的群落结构存在差异。综上, 随着生物结皮由藻向藓的发育演替, 其土壤导水性呈现先降低后增加的趋势, 而土壤持水性表现为先增加后降低的变化规律。  相似文献   
60.
近年来迅速流行的苔藓微景观是一个将植物与装饰通过设计布景,巧妙形成的微缩风景。通过对微景观的起源、作用、设计与制作方法等的分析,并通过实例阐述了微景观的制作步骤,以期对微景观的设计与创作提供参考与借鉴。  相似文献   
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