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91.
The application of geotextile mats constructed from the palm leaves of Borassus aethiopum (Borassus) and Mauritia flexuosa (Buriti) was investigated in field experiments. The use of geotextiles caused improved soil moisture storage during dry summer periods on a steep (21–25°) roadside slope in Lithuania. The enhanced soil moisture under the Borassus and Buriti mats encouraged better root development of perennial grasses, increased the number and weight of earthworms and increased the dry biomass of perennial grasses by 50.5 and 18.2%, respectively, compared with a grassland control. The mean rate of water erosion from bare soil during the study period from 17/04/2007 to 11/12/2008 was 33.21 Mg/ha. The cover of palm‐mat geotextiles decreased soil losses from bare fallow soil by 94.8–91.1%. An erosion rate of 0.85 Mg/ha over this 21‐month period was measured on the slope under perennial grasses without geotextile cover. Application of geotextile cover on perennial grasses completely prevented soil erosion by water. Therefore, use of geotextiles has clear soil and water conservation benefits on industrial slopes susceptible to erosion. The use of geotextiles has multiple benefits including soil conservation, the improvement of plant growth conditions and the encouragement of earthworm populations. 相似文献
92.
《Communications in Soil Science and Plant Analysis》2012,43(19):2552-2564
Oat is widely used as a food source in human and animal diets. In China, supplementary cultivation of oat has recently been extended into marginal saline soils, due to its extensive use. The goal of the present study was to explore and compare the agronomic characteristics, biomass production, and distribution of oat in coastal saline soil. A single-factor randomized block design experiment with six naked and husked oat varieties [Bayou-1 (BU-1), Baiyan-2 (BY-2), Baiyan-7 (BY-7), Huawan-6 (HW-6), Huazao-2 (HZ-2), and Pin-16 (P-16)] as treatments was conducted in the Hebei Province of China. The growth period (77 to 88 days) of the six oat varieties were shorter in saline soil than their original breeding region. Moreover, the plant was shorter, with a lower grain number per plant and seed setting. Grain weight increased and no change was observed in the floret number in coastal saline soil relative to the original habitats. The BY-7 variety produced the highest biomass value of 7.0 t ha?1 compared to the other five varieties. Compared with two active growth points, most varieties in the present study showed just one growth activity point between elongation and heading. Two fast growth periods for the six oat varieties were due to the high total leaf biomass growth rate (BGR) from elongation to heading and panicle BGR from heading to maturity. The biomass growth ratio (BGO) during elongation to heading was the largest among the four growth stages of the oat varieties. The number of kernels per spike decreased at the research site, but grain weight increased. Substantial differences were observed for growth periods, biomass, BGR, BGO, and other agronomic characters in the coastal saline soil of North China, but the BY-7 variety was the most suitable variety for the study site. 相似文献
94.
Helge Green Nina Heiberg Kirsten Lejbølle Dan Funck Jensen 《European journal of plant pathology / European Foundation for Plant Pathology》2001,107(3):349-359
The activity of Trichoderma harzianum in the spermosphere and rhizosphere of different plant species was studied by use of a beta-glucuronidase (GUS) transformant (strain T3a). Hereby, direct observation of micro-habitats supporting metabolic activity of T. harzianum is reported. Germination of conidia and mycelial growth were not supported by exudates from healthy roots of various ages. Instead, growth and activity of T. harzianum depended on access to dead organic substrates such as seed coats, decaying roots, and wounds, including those caused by infecting pathogens. A correlation between the GUS activity of T. harzianum and the biomass of Pythium ultimum in infected roots was established. On the basis of our observations, we suggest that the biocontrol ability of T. harzianum involves competition with the pathogen for substrates including the seed coat, and wounded or infected root tissue. 相似文献
95.
96.
青藏高原几种嵩草的生物量及其幼苗生长发育的初步研究 总被引:6,自引:0,他引:6
研究了青藏高原4种嵩草属植物的枝条发育状况,生物量积累特征以及3种嵩草幼苗的生长发良规律。结果表明;各嵩草营养枝条的季节变化有两个高峰期,而线叶蒿草的生殖枝有一个明显的高峰期,其它嵩草无高期峰。 相似文献
97.
1988年,利用红豆草改良长芒草草地,建设人工割草场,显著提高了草地生产能力,经对1988-191年该草地地上生物量试验资料进行统计分析,建立了地上生物量动态模型。为管理,保护,合理利用同类草地,发展畜牧业提供了科学依据。 相似文献
98.
辽东半岛结缕草无性系种群构件生物量相关模型及形成规律 总被引:5,自引:2,他引:5
按生物构件的理论,分析了辽东半岛结缕草无性系种群叶片、叶鞘、分株、匍匐茎各构件生物量以及总生物量间的相关模型和构件生物量的分配、形成规律,探讨了其不同生物量基于种群大小(密度)的形成规律。结果表明,辽东半岛结缕草无性系种群的总生物量及各构件生物量均随着种群密度的增大而以线性函数增加,各构件生物量与总生物量以及各构件生物量间亦均以线性函数增加,生物量增加比率均表现为:分株>匍匐茎,叶鞘>叶片,总生物量增量的27.2%分配给叶片,29.2%分配给叶鞘,43.6%分配给匍匐茎,叶片,叶鞘和匍匐茎构件生物量的积累是按1∶1.1∶1.6比例形成。 相似文献
99.
100.
层次分析法是一种将决策者对复杂系统的决策思维过程模型化、数量化的过程.采用层次分析法,对影响和指示土地退化的生物量、归一化植被指数、土壤水分指数和土壤盐碱化4个影响因子进行分析.通过计算每个影响因子的权重,基于ASTER,SPOT,TM,MODIS产品以及野外调查数据等多源数据,对新疆艾比湖地区2000年8月至2004年8月的土地退化状况进行了评价,并且分析了层次分析法应用于土地退化研究的适用性及其优缺点.研究表明:艾比湖地区耕地退化现象普遍,占耕地总面积的55.78%,分布广,程度重. 相似文献