نتایج جستجو برای: the ecological forest monitoring programs

تعداد نتایج: 16167887  

Journal: :caspian journal of environmental sciences 2011
h. pourbabaei r. abedi

the objective of this research was to identify and describe the different ecological species groups (vegetation types) present in the rural heritage museum of guilan. the study area was approximately 260 ha, which is located in the saravan forest park in guilan province, north of iran. sampling procedure was performed with a systematic random technique. a total of 89 plots were sampled. classif...

2004
Robert Cameron

Air pollution and climate change are threats to maintaining ecological health of protected areas. Protected Area managers require a meaningful way to measure impacts of these threats. Lichens provide a relevant, sensitive and measurable indicator for long-term monitoring. Hundreds of studies have linked lichen communities to air quality, and several long-term lichen monitoring programs in Europ...

Although the vulnerability assessment of forest parks is used to determine the threats they face, a rapid and holistic framework has not been established well. The primary objective of this study is to adopt a framework for rapid assessment of forest parks vulnerability, examined in Lavizan forest park in Tehran (Iran) as the case study. The vulnerability assessment has been conducted, using th...

2017
Valverde and Morales

A series of functional variables, including biomass and hymenial area, were obtained for more than 4800 individual macrofungal sporocarps and correlated with a set of ecological parameters characterizing soil, climate and forest structure in four different forest types of Costa Rica. The idea behind this project was to document macrofungi over a three-year period with the objective of generatin...

2001
JoAnn M. Hanowski Gerald J. Niemi

We established bird monitoring programs in two regions of Minnesota: the Chippewa National Forest and the Superior National Forest. The experimental design defined forest cover types as strata in which samples of forest stands were randomly selected. Subsamples (3 point counts) were placed in each stand to maximize field effort and to assess within-stand and between-stand variation for a variet...

Journal: :journal of agricultural science and technology 2010
a. farzaneh

forest classification on the basis of satellite images is a promising technique both for primary map production and for map updating and forest monitoring. for accurate for-est classification into three classes, using mapping by canopy cover density “high spatial resolution satellite images have to be used in order to obtain the required spatial detail” [schneider, 1999]. at the same time, the ...

Journal: :International Journal of Geographical Information Science 2010
Thomas K. Alexandridis Thomas Katagis Ioannis Z. Gitas Nikolaos G. Silleos K. M. Eskridge G. Gritzas

Monitoring vegetation condition is an important issue in the Mediterranean region, in terms of both securing food and preventing fires. Vegetation indices (VIs), mathematical transformations of reflectance bands, have played an important role in vegetation monitoring, as they depict the abundance and health of vegetation. Instead of storing raster VI maps, aggregated statistics can be derived a...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه سیستان و بلوچستان 1390

the changes in todays world organization, to the extent that instability can be characterized with the most stable organizations called this afternoon. if you ever change management component, an additional value to the organization was considered, today, these elements become the foundation the organization is survival. the definition of the entrepreneur to identify opportunities to exploit a...

2015
Jien Zhang Tianming Wang Jianping Ge Jian Liu

In the aftermath of the severe droughts and floods at the end of the 20th century, the Chinese government launched several ecological restoration projects, including the Natural Forest Protection Program in 1998 and the Grain-for-Green Program in 1999, to promote afforestation and reforestation to reduce surface runoff and consequent soil erosion nationwide. However, it is still unclear how veg...

2018
D A Orwig P Boucher I Paynter E Saenz Z Li C Schaaf

Contemporary terrestrial laser scanning (TLS) is being used widely in forest ecology applications to examine ecosystem properties at increasing spatial and temporal scales. Harvard Forest (HF) in Petersham, MA, USA, is a long-term ecological research (LTER) site, a National Ecological Observatory Network (NEON) location and contains a 35 ha plot which is part of Smithsonian Institution's Forest...

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