Response of soil respiration to environmental and photosynthetic factors in different subalpine forest-cover types in a loess alpine hilly region

Author(s):  
Yuanhang Li ◽  
Sha Lin ◽  
Qi Chen ◽  
Xinyao Ma ◽  
Shuaijun Wang ◽  
...  
2006 ◽  
Vol 23 (2) ◽  
pp. 114-121 ◽  
Author(s):  
Harry A. Kahler ◽  
James T. Anderson

Abstract We assessed and compared tree cavity resources for dependent wildlife among various forest cover types of West Virginia. The study was conducted in the Greenbrier and Potomac Ranger Districts of the Monongahela National Forest (MNF). From the fall of 1999 through the spring of 2001, 25 50-m radius study plots were established in each of a Society of American Foresters (SAF) central hardwood, northern hardwood, and subalpine forest cover type. Cavity tree abundance significantly differed among the three forest cover types (P < 0.0001), with the highest cavity tree abundance in the central hardwood type (x¯ = 16.4; SE = 5.3), followed by the northern hardwood type (x¯ = 12.7; SE = 6.8), and lastly the subalpine type (x¯ = 7.2; SE = 3.6). Relative cavity likelihood was highest for black locust (Robinia pseudoacacia), followed by American beech (Fagus grandifolia), sugar maple (Acer saccharum), and chestnut oak (Quercus prinus). American beech cavity numbers currently may be influenced by increased mortality from recent outbreaks of beech bark disease, initiated by the beech scale insect (Cryptococcus fagisuga). Management of red spruce (Picea rubens) forests should consider numbers of nearby large hardwoods to provide cavity resources for dependent wildlife.


1998 ◽  
Vol 29 (3) ◽  
pp. 221-244 ◽  
Author(s):  
Robert O. Hudson ◽  
Douglas L. Golding

Chemical profiles in snowpacks were observed during snow accumulation and melt periods at subalpine sites in the southern interior of British Columbia. During accumulation periods, concentrations of nitrate, sulphate, chloride and sodium were higher than those of bulk snowfall in surface snowpack layers and lower in middle and basal layers. During melt periods, the opposite was true. This process of chemical profile reversals was found to repeat itself through successive cycles of melt and non-melt periods that typically occur at the site during the spring. This recurring cycle of chemical enrichment resulted in two distinct processes of ion elution. A “seasonal” process was observed in which there is an initial ion pulse followed by a slow exponential decline in concentration. An event based process consisting of ion pulses due to leaching of enriched surface layers was superimposed on the seasonal process. Forest cover type was found to exert an influence on snowpack chemistry during accumulation and melt. Significant differences between forest cover types were found among average chemical concentrations in enriched and depleted layers, suggesting that canopy density causes differences in chemical metamorphosis of snowpacks.


1993 ◽  
Vol 69 (6) ◽  
pp. 667-671 ◽  
Author(s):  
John A. Drieman

The need for a current, regional perspective of the forest of Labrador was identified. Mapping of forest cover types, peat-lands, recent burns and clearcut disturbances was accomplished through visual interpretation of 1:1,000,000 scale Landsat Thematic mapper colour composite transparencies and the transfer of interpreted polygons to a geographic information system. The mapping and verification process is described in this paper. The end product, a forest resource map, provides the most up-to-date and detailed information on Labrador's forest cover types and disturbances available on a single map. The digital format of the map facilities area summaries, viewing and printing.


2017 ◽  
Vol 31 (2) ◽  
pp. 209-219 ◽  
Author(s):  
Ronggo Sadono ◽  
Hartono Hartono ◽  
Mochammad Maksum Machfoedz ◽  
Setiaji Setiaji

Volcanic eruption is one of the natural factors that affect land cover changes. This study aimed to monitor land cover changes using a remote sensing approach in Cangkringan Sub-district, Yogyakarta, Indonesia, one of the areas most vulnerable to Mount Merapi eruption. Three satellite images, dating from 2001, 2006 and 2011, were used as main data for land cover classification based on a supervised classification approach. The land cover detection analysis was undertaken by overlaying the classification results from those images. The results show that the dominant land cover class is annual crops, covering 40% of the study area, while the remaining 60% consists of forest cover types, dryland farming, paddy fields, settlements, and bare land. The forests were distributed in the north, and the annual crops in the middle of the study area, while the villages and the rice fields were generally located in the south. In the 2001–2011 period, forests were the most increased land cover type, while annual crops decreased the most, as a result of the eruption of Mount Merapi in 2010. Such data and information are important for the local government or related institutions to formulate Detailed Spatial Plans (RDTR) in the Disaster-Prone Areas (KRB).


2008 ◽  
Vol 32 (2) ◽  
pp. 53-59 ◽  
Author(s):  
Jason R. Applegate

Abstract An inventory of down woody materials (DWM) was conducted on Fort A.P. Hill, Virginia, to develop a baseline of DWM abundance and distribution to assist in wildland fire management. Estimates of DWM are necessary to develop accurate assessments of wildfire hazard, model wildland fire behavior, and establish thresholds for retaining DWM, specifically CWD (coarse woody debris), as a structural component of forest ecosystems. DWM were sampled by forest type and structure class using US Forest Service, Forest Inventory and Analysis (FIA) field procedures. DWM averaged 12–16 tn/ac depending on forest cover type and structure class. Coarse woody debris (CWD) averaged 2.7–13.0 tn/ac depending on forest cover type and structure class. CWD comprised more than 70% of DWM across all forest cover types and structure classes. Fine woody debris (FWD) averaged 0.05–3.2 tn/ac depending on fuel hour class, forest cover type, and structure class. DWM was consistently higher in mature (sawtimber) forests than in young (poletimber) forests across all forest cover types, attributed to an increased CWD component of DWM. The variability associated with DWM suggests that obtaining robust estimates of CWD biomass will require a higher sampling intensity than FWD because of its nonuniform distribution in forest systems. FIA field procedures for tallying and quantifying DWM were practical, efficient, and, subsequently, included as permanent metrics in Fort A.P. Hill's Continuous Forest Inventory program.


2014 ◽  
Vol 955-959 ◽  
pp. 3803-3812
Author(s):  
Guang Di Li ◽  
Guo Yin Wang ◽  
Xue Rui Zhang ◽  
Wei Hui Deng ◽  
Fan Zhang

Storm is the most popular realtime stream processing platform, which can be used to deal with online machine learning. Similar to how Hadoop provides a set of general primitives for doing batch processing, Storm provides a set of general primitives for doing realtime computation. SAMOA includes distributed algorithms for the most common machine learning tasks like Mahout for Hadoop. SAMOA is both a platform and a library. In this paper, Forest cover types, a large benchmaking dataset available at the UCI KDD Archive is used as the data stream source. Vertical Hoeffding Tree, a parallelizing streaming decision tree induction for distributed enviroment, which is incorporated in SAMOA API is applied on Storm platform. This study compared stream prcessing technique for predicting forest cover types from cartographic variables with traditional classic machine learning algorithms applied on this dataset. The test then train method used in this system is totally different from the traditional train then test. The results of the stream processing technique indicated that it’s output is aymptotically nearly identical to that of a conventional learner, but the model derived from this system is totally scalable, real-time, capable of dealing with evolving streams and insensitive to stream ordering.


2006 ◽  
Vol 20 (3) ◽  
pp. n/a-n/a ◽  
Author(s):  
Russell K. Monson ◽  
Sean P. Burns ◽  
Mark W. Williams ◽  
Anthony C. Delany ◽  
Michael Weintraub ◽  
...  

2010 ◽  
Vol 86 (1) ◽  
pp. 77-86 ◽  
Author(s):  
Andrea J. Maxie ◽  
Karen F. Hussey ◽  
Stacey J. Lowe ◽  
Kevin R. Middel ◽  
Bruce A. Pond ◽  
...  

In a portion of central Ontario, Canada we assessed the classification agreement between field-based estimates of forest stand composition and each of two mapped data sources used in wildlife habitat studies, the Forest Resource Inventory (FRI) and satellite-image derived Provincial Land Cover (PLC). At two study areas, Algonquin Provincial Park (APP) and Wildlife Management Unit 49 (WMU49), we surveyed 119 forest stands and 40 water and wetland stands. Correspondence levels between FRI and field classifications were 48% in APP and 44% in WMU49 when assessing six forest cover types. With only four simplified forest cover types, levels improved to 77% in APP and 63% in WMU49. Correspondence between PLC and field classifications for three forested stand types was approximately 63% in APP and 55% in WMU49. Because of the poor to moderate level of correspondence we detected between map and field classifications, we recommend that care be exercised when FRI or PLC maps are used in forest and wildlife research and management planning. Key words: forest resource inventory, FRI, provincial land cover, PLC, Landsat Thematic Mapper, map accuracy, map correspondence, map agreement, Ontario, wildlife habitat


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