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81.
Evaluation of existing on-farm agroforestry plots should provide useful supplementary information for the design of improved agroforestry systems, in both research and development projects. Such evaluation has been little used, however, largely due to the methodological difficulties of surveying highly variable on-farm plots, and difficulties in identifying key variables for measurement. This paper describes a set of methods and tools used in evaluating plots of alley-cropping and tree borders around crop fields established by farmers working with the CARE Agroforestry Extension Project in western Kenya. Details of survey design, sampling, and implementation are discussed, and suggestions made for carrying out agroforestry surveys in other projects. A condensed version of the questionnaire is appended. 相似文献
82.
Kasper Johansen Stuart Phinn Ian Dixon Michael Douglas John Lowry 《Forest Ecology and Management》2007,240(1-3):42-60
Suitable methods for measuring and monitoring the condition of riparian environments are being investigated by government agencies responsible for maintaining these environments in Australia. The objective of this work was to compare two riparian condition assessment approaches, the Tropical Rapid Appraisal of Riparian Condition (TRARC) method developed for rapid on-ground assessment of the environmental condition of savanna riparian zones and an image based riparian condition monitoring scheme. Measurements derived from these two approaches were compared and correlated. The sample representativeness of the TRARC method was evaluated and the cost-effectiveness and suitability for multi-temporal analysis of the two approaches were assessed. Two high spatial resolution multi-spectral QuickBird satellite images captured in 2004 and 2005 and coincident field data covering sections of the Daly River in the Northern Territory, Australia were used in this work. Both field and image data were processed to map indicators of riparian zone condition including percentage canopy cover, organic litter on the ground, canopy continuity, tree clearing, bank stability, and flood damage. Spectral vegetation indices, image segmentation, and supervised classification were used to produce riparian health indicator maps. QuickBird image data were used to examine if the spatial distribution of TRARC transects provided a representative sample of ground based estimates of riparian health indicators. Covering approximately 3% of the study area, the sample mean of the TRARC estimates of individual indicators of riparian zone condition were in most cases within 20% of the global mean derived from the whole imaged riparian area. The cost-effectiveness of the image based approach was compared to that of the ground based TRARC method. Results showed that the TRARC method was more cost-effective at spatial scales from 1 km to 200 km of river in relatively homogeneous riparian zones along rivers with only one channel, while image based assessment becomes more feasible at regional scales (200–2000 km of river). A change detection analysis demonstrated that image data can provide detailed information on gradual change, while the TRARC method is less suited for multi-temporal analysis due to the ranked data format, which inhibits precise detection of change. However, results from both methods were considered to complement each other for single date assessment of riparian zones if used at appropriate spatial scales. 相似文献
83.
Sabine Augustin Jan Evers Hans-Peter Dietrich Johannes Eichhorn Thomas Haussmann Regina Icke Ansgar Isenberg Wolfgang Lux Monica Musio Hans Pretzsch Winfried Riek Thomas Rötzer Bernd Schultze Andreas Schulze Jörg Schröder Walter Seidling Nicole Wellbrock Klaus von Wilpert Barbara Wolff 《European Journal of Forest Research》2005,124(4):251-260
In the 1970s unexpected forest damages, called “new type of forest damage” or “forest decline”, were observed in Germany and
other European countries. The Federal Republic of Germany and the German Federal States implemented a forest monitoring system
in the early 1980s, in order to monitor and assess the forest condition. Due to the growing public awareness of possible adverse
effects of air pollution on forests, in 1985 the ICP Forests was launched under the convention on long-range transboundary
air pollution (CLRTAP) of the United Nations Economic Commission for Europe (UN-ECE). The German experience in forest monitoring
was a base for the implementation of the European monitoring system. In 2001 the interdisciplinary case study “concept and
feasibility study for the integrated evaluation of environmental monitoring data in forests”, funded by the German Federal
Ministry of Education and Research, concentrated on in-depths evaluations of the German data of forest monitoring. The objectives
of the study were: (a) a reliable assessment of the vitality and functioning of forest ecosystems, (b) the identification
and quantification of factors influencing forest vitality, and (c) the clarification of cause-effect-relationships leading
to leaf/needle loss. For these purposes additional data from external sources were acquired: climate and deposition, for selected
level I plots tree growth data, as well as data on groundwater quality. The results show that in particular time series analysis
(crown condition, tree growth, and tree ring analysis), in combination with climate and deposition are valuable and informative,
as well as integrated evaluation of soil, tree nutrition and crown condition data. Methods to combine information from the
extensive and the intensive monitoring, and to transfer process information to the large scale should be elaborated in future.
相似文献
Sabine AugustinEmail: |
84.
VEGETATION植被指数与森林资源的相关性分析 总被引:1,自引:0,他引:1
周科松 《中南林业调查规划》2005,24(2):34-36,41
VEGETATION植被指数与森林资源特征因子之间的相关性是该遥感数据用于森林资源监测的基础.基于湖南省同期的连清样地资料、ETM卫片,采用统计分析、单因素方差分析、迭加观察等方法,对VEGETATION植被指数与森林资源特征因子之间的相关性进行了分析,发现两者之间存在较高的相关性. 相似文献
85.
86.
江苏、河南、安徽和山东四省小麦纹枯病菌对井冈霉素的敏感性监测 总被引:4,自引:2,他引:2
采用菌丝生长速率法监测了1984、2001和2010年江苏省小麦纹枯病菌Rhizoctonia cerealis对井冈霉素的敏感性变化趋势,以及2010年河南、安徽和山东3省小麦纹枯病菌对井冈霉素的敏感性现状。结果表明:1984、2001和2010年江苏省小麦纹枯病菌对井冈霉素的EC50值范围分别为0.31~0.87、0.05~1.21和0.20~1.09 μg/mL,26年间江苏省小麦纹枯病菌对井冈霉素的敏感性未发生显著性变化;2010年河南、安徽和山东3省小麦纹枯病菌对井冈霉素的EC50值范围分别为0.15~1.16、0.43~0.90和0.09~1.33 μg/mL,4省小麦纹枯病菌对井冈霉素的敏感性相互间差异不显著。井冈霉素仍然可以作为防治小麦纹枯病的主要药剂。 相似文献
87.
88.
为提高低空间分辨率遥感影像在卫星林火监测部门的应用质量,获取更准确的火灾信息,制作可视效果更好、便于基层部门使用的卫星林火监测图像。本研究以2013年2月6日云南省大理市黄家村森林火灾为背景,研究了一种基于亚像元分解与增强技术的卫星林火监测图像制作技术。结果表明,通过亚像元分解与增强技术,对空间分辨率低的气象卫星遥感图像进行处理,可得到空间分辨率为30 m的图像产品,能够将低分辨率遥感影像处理成超分辨率的遥感影像图像。该技术可应用于林火监测部门发布相关的监测图像。 相似文献
89.
退耕还林工程建设监理启动难,推广实施缓慢,其中有许多理论和实际问题值得研究。本文就当前退耕还林工程建设监理中常遇到的管理与监理的关系,建设单位与施工单位的界定,监理单位的责任等问题进行了论述,并就如何解决工程建设监理经费等问题提出了建议。 相似文献
90.
气吸式精密播种机种肥监测设备的研制 总被引:1,自引:0,他引:1
介绍了一种对气吸式精密播种机的播种和施肥情况进行监测的电子设备。使用先进的16位单片机SPCE061A作为控制器件,利用该控制器的高速处理能力,对返回信号进行分析。应用模糊识别与优选法等处理算法,能够及时跟随每个传感器工作环境的随机变化,准确反映各传感器的工作状态。同时,简化了硬件电路设计,降低了成本,实现了自适应功能。 相似文献