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991.
寄主植物对舞毒蛾生长发育的影响 总被引:8,自引:0,他引:8
该文选择了青杨Populus cathayanaRehd.、华北落叶松Larix principis-rupprechtiiMayr.和山杏Aarmeniaca sibiricaLinn.,研究植物对舞毒蛾Lymantria disparL.生长发育历期、蛹重、产卵量的影响。结果表明舞毒蛾发育历期、蛹重及产卵量与所取食的寄主植物有明显的相关性,取食华北落叶松的舞毒蛾个体发育历期最短,平均为38.22±0.56 d,蛹最重,平均为1.48±0.09g,产卵量最多,平均每雌560.65±41.67粒;取食青杨的舞毒蛾发育历期最长,平均为46.68±0.65 d,蛹最轻,平均为1.17±0.08 g,产卵量最少,平均每雌315.47±49.07粒;取食山杏的舞毒蛾间于二者之间,平均历期为39.53±0.58 d,平均蛹重为1.24±0.08 g,每雌产卵量394.50±58.65粒。可以认为,在供试范围内华北落叶松最适宜舞毒蛾生长发育,山杏次之,青杨最不适宜。 相似文献
992.
生态园林中的植物造景 总被引:3,自引:0,他引:3
阐述了生态园林的概念和科学内涵,并结合植物景观设计要求,提出生态园林中植物配置的原则,详细论述了生态型造景的类型及产生的效益,并提出植物配置时应注意的问题,以期为生态园林建设提供帮助. 相似文献
993.
Kripal Singh Ashish Kumar Mishra Bajrang Singh Rana P. Singh Dharani Dhar Patra 《Land Degradation \u0026amp; Development》2016,27(2):223-230
Tillage modifies soil structure and has been suggested as a practice to improve physical, hydrological and chemical properties of compacted soils. But little is known about effect of long‐term tillage on physicochemical soil properties and crop yield on sodic soils in India. Our objective was to investigate the effect of different tillage regimes on crop yield (wheat and paddy rice) and physicochemical properties of sodic soils. Two sodic sites under conventional tillage for 5 (5‐YT; 5‐year tillage) and 9 (9‐YT; 9‐year tillage) years were selected for this study. Changes in crop yield and physicochemical soil properties were compared with a control, sodic land without any till history, that is, 0‐year tillage/untilled (0‐YT). Five replicated samples at 0‐ to 10‐cm and 10‐ to 20‐cm soils depths were analysed from each site. In the top, 0‐ to 10‐cm soil depth 5‐YT and 9‐YT sites had higher particle density (Pd), porosity, water holding capacity, hydraulic conductivity, organic carbon, total nitrogen (Nt), available nitrogen (Navail), phosphorus (Pavail) and exchangeable calcium (Exch. Ca++) than 0‐YT, whereas bulk density (Bd), C : N ratio and CaCO3 were significantly lower. Bd, pH, EC and CaCO3 increased significantly with depth in all the lands, whereas Pd, porosity, water holding capacity, hydraulic conductivity, organic carbon, Nt, Navail, Pavail and Exch. Ca++ decreased. We conclude that continuous tillage and cropping can be useful for physical and chemical restoration of sodic soils. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
994.
Pietro P. C. Aucelli Massimo Conforti Marta Della Seta Maurizio Del Monte Lorenzo D'uva Carmen M. Rosskopf Francesca Vergari 《Land Degradation \u0026amp; Development》2016,27(4):1075-1092
This paper focuses on the analysis of the slope and catchment erosion dynamics in a typical Mediterranean context and its sensitivity to recent climatic and socio‐economic changes. The main objective of the present study is to test the reliability of digital photogrammetric analysis to evaluate the time and space evolution of erosion processes mainly triggered by surface running waters and landslides for about the last 60 years. The selected test area is the Landola catchment, a minor tributary of the Upper Orcia River Valley (Southern Tuscany). The Upper Orcia valley is a key site for the comprehension of denudation processes typically acting in Mediterranean badland areas thanks to the following: (i) the availability of long‐lasting erosion monitoring datasets (20 years' long direct measurements at erosion ‘hot spots’); (ii) its representativeness as a sub‐humid Mediterranean badland area; and (iii) the rapidity of development of erosion processes, which makes it suitable as an open‐air laboratory for the study of badland dynamics. The outputs of this work highlight that the application of high‐resolution digital photogrammetric methodologies can represent a powerful and low‐cost tool to evaluate rates and spatial–temporal distribution of denudation processes, as confirmed by the validation through field point monitoring in areas close to the study area. The results obtained for the study area confirm that high erosion rates are a persistent environmental problem for the Upper Orcia Valley, which is not solved up to now, despite various land conservation interventions. The performed multi‐temporal analysis shows a slight decrease in the average water erosion rate during the last 60 years and a parallel increase in the frequency of mass wasting events. These variations are most likely related to a complex interplay between land use changes that have affected the study area during the studied period, revealing a very delicate equilibrium between farming activities and erosion processes. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
995.
捕食性昆虫螨类及蜘蛛的捕食作用 总被引:5,自引:0,他引:5
文章综述了昆虫、螨类及蜘蛛捕食作用研究的近况,重点介绍了昆虫及捕食性螨类和蜘蛛的捕食功能反应,血清学法研究捕食作用的概况,分析了ELISA法的优缺点,并总结了捕食作用的研究现状,指出了面临的问题及发展方向。 相似文献
996.
997.
应用生命表方法分析吡虫啉、木虱净、稻虱净3种化学农药对橄榄星室木虱的控制效果。结果表明:吡虫啉、木虱净、稻虱净和对照的种群趋势指数分别为0.4148,0.8328,4.9908,6.3925。说明吡虫啉和木虱净处理区的橄榄星室木虱种群数量呈下降趋势,稻虱净和对照区的橄榄星室木虱种群数量以4.9908和6.3925倍的速度增长;吡虫啉、木虱净和稻虱净的干扰作用控制指数分别为0.0649,0.1303和0.7807。表明吡虫啉和木虱净施用区种群数量相当于对照区的6.49%和13.03%,取得了很好的防治效果;稻虱净施用区种群数量是对照的78.07%,不是防治橄榄星室木虱的理想药剂。 相似文献
998.
999.
厦门白蚁种类名录与常见白蚁的防治 总被引:1,自引:1,他引:1
记载厦门白蚁种类4科12属21种,其中9种为厦门新记录种。为害林木的主要有家白蚁、黑翅土白蚁、黄翅大白蚁,介绍了此3种白蚁常见寄主及防治方法。 相似文献
1000.
TIAN Xiaorui SHU Lifu WANG MingyuThe Research Institute of Forest Ecology. Environment Protection. Chinese Academy of Forestry. Beijing . China 《中国林业科技(英文版)》2002,(4)
The fuelbreaks were established in south China from 1950s. With the active work of local communities and state government, the fuelbreaks have been built for 398,000 kilometers. In some areas, fuelbreaks and firebreaks have constructed a network primarily, such as in the provinces of Fujian, Guangdong, Guangxi. The fuelbreaks can prevent forest fire effectively. That has been approved by actual examples and burning tests. The fuelbreaks also benefit the forest ecosystem and environment. This paper makes a review on fuelbreaks research and application in China, discussed present research achievements about fuelbreaks mechanism and its development. In the future, the Chinese government and local communities will increase investment in the construction of firebreaks network with fuelbreaks as focal points. 相似文献