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Compensation for forest ecological services in China

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forestry Studies in China 2007年第1期9卷 68-79页

作者： Liu Can Wang Sen Zhang Wei Liang Dan China National forestry Economics Development Research Center Beijing 100714 E R. China Ppacific forestry Centre Canadian Forest Service Natural Resources Canada 506 West Burnside Road Victoria B C Canada Department of Agricultural Economics Michigan State University MI 48824-1039 USA

The paper discusses methods to compensate for the costs incurred in the supply of forest ecological services （FES）, i.e. government dominated and market-based instruments as well as progress made so far in China. Fa... 详细信息

关键词： forest ecological services (FES) compensation mechanism forest economics policy

Evaluating the Impacts of Using Different Digital Surface Models to Estimate forest Height with TanDEM-X Interferometric Coherence Data

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雷达学报（中英文） 2020年第2期9卷 386-398页

作者： CHEN Hao HILL David A. WHITE Joanne C. CLOUDE Shane R. canadian forest service 506 Burnside Road WestVictoriaBritish ColumbiaV8Z 1M5Canada Applied Electromagnetics Consultants 26 Westfield AvenueCuparFifeKY155AAUK

In our previous studies, we demonstrated the usefulness of TanDEM-X interferometric bistatic mode with single polarization to obtain forest heights for the purposes of large area mapping. A key feature of our approach has been the use of a simplified Random Volume Over Ground(RVOG) model that locally estimates forest height. The model takes TanDEM-X interferometric coherence amplitude as an input and uses an external Digital Surface Model(DSM) to account for local slope variations due to terrain topography in order to achieve accurate forest height estimation. The selection of DSM for use as a local slope reference is essential, as an inaccurate DSM will result in less accurate terrain-correction and forest height estimation. In this paper, we assessed TanDEM-X height estimates associated with scale variations in different DSMs used in the model over a remote sensing supersite in Petawawa, canada. The DSMs used for assessments and comparisons included ASTER GDEM, ALOS GDSM, airborne DRAPE DSM, canadian DSM and TanDEM-X DSM. Airborne Laser Scanning(ALS) data were used as reference for terrain slope and forest height comparisons. The results showed that, with the exception of the ASTER GDEM, all DSMs were sufficiently accurate for the simplified RVOG model to provide a satisfactory estimate of stand-level forest height. When compared to the ALS 95th height percentile, the modeled forest heights had R2 values greater than 80% and Root-Mean-Square Errors(RMSE)less than 2 m. For a close similarity in slope estimation with the ALS reference, coverage across canada and open data access, the 0.75 arc-second(20 m) resolution canadian DSM was selected as a preferred choice for the simplified RVOG model to provide TanDEM-X height estimation in canada.

关键词： Interferometric COA Digital surface model forest height

Phylogenetic Analysis of Orgyia pseudotsugata Single-nucleocapsid Nucleopolyhedrovirus

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中国病毒学 2007年第4期22卷 257-265页

作者： Agata Jakubowska Monique M. van Oers Imre S. Otvos Just M. Vlak Laboratory of Virology Wageningen UniversityBinnenhaven 11Wageningen6709 PDThe Netherlands Department of Biological Control and Quarantine Institute of Plant ProtectionMiczurina 20 Poznan 60-318 Poland natural resources canada Canadian Forest Service Pacific Forestry Centre 506 West Burnside Road BC V8Z 1M5 Victoria Canada

The Douglas-fir tussock moth Orgyia pseudotsugata (Lepidoptera: Lymantriidae) is a frequent defoliator of Douglas-fir and true firs in western USA and canada. A single nucleopolyhedrovirus (SNPV) isolated from O. pseudotsugata larvae in canada (OpSNPV) was previously analyzed via its polyhedrin gene, but is phylogenetic status was ambiguous. Sequences of four conserved baculovirus genes, polyhedrin, lef-8, pif-2 and dpol, were amplified from OpSNPV DNA in polymerase chain reactions using degenerate primer sets and their sequences were analyzed phylogenetically. The analysis revealed that OpSNPV belongs to group II NPVs and is most closely related to SNPVs that infect O. ericae and O. anartoides, respectively. These results show the need for multiple, concatenated gene phylogenies to classify baculoviruses.

关键词：基因分析核型多角体病毒单核壳体生物防治花旗松鳞翅目害虫系统演化

Dynamics of dead wood decay in Swiss forests

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forest Ecosystems 2020年第3期7卷 462-477页

作者： Oleksandra Hararuk Werner A.Kurz Markus Didion Department of Biology University of Central Florida4110 Libra DrOrlandoFL32816USA Pacific forestry Centre 506 Burnside Road WestVictoriaBritish ColumbiaV8Z 1M5Canada Swiss Federal Research Institute WSL Zürcherstrasse 1118903BirmensdorfSwitzerland

Background: forests are an important component of the global carbon(C) cycle and can be net sources or sinks of CO2, thus mitigating or exacerbating the effects of anthropogenic greenhouse gas emissions. While forest productivity is often inferred from national-scale yield tables or from satellite products, forest C emissions resulting from dead organic matter decay are usually simulated, therefore it is important to ensure the accuracy and reliability of a model used to simulate organic matter decay at an appropriate scale. National forest Inventories(NFIs) provide a record of carbon pools in ecosystem components, and these measurements are essential for evaluating rates and controls of C dynamics in forest ecosystems. In this study we combine the observations from the Swiss NFIs and machine learning techniques to quantify the decay rates of the standing snags and downed logs and identify the main controls of dead wood ***: We found that wood decay rate was affected by tree species, temperature, and precipitation. Dead wood originating from Fagus sylvatica decayed the fastest, with the residence times ranging from 27 to 54 years at the warmest and coldest Swiss sites, respectively. Hardwoods at wetter sites tended to decompose faster compared to hardwoods at drier sites, with residence times 45–92 and 62–95 years for the wetter and drier sites, *** wood originating from softwood species had the longest residence times ranging from 58 to 191 years at wetter sites and from 78 to 286 years at drier ***: This study illustrates how long-term dead wood observations collected and remeasured during several NFI campaigns can be used to estimate dead wood decay parameters, as well as gain understanding about controls of dead wood dynamics. The wood decay parameters quantified in this study can be used in carbon budget models to simulate the decay dynamics of dead wood, however more measurements(e.g. of soil C dynamics at the same plots)

关键词： Carbon residence time Carbon dynamics National forest Inventory

Desertification and Dust Storms in China: Impacts, Root Causes and Mitigation Strategies

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Chinese forestry Science and Technology 2006年第3期5卷 22-35页

作者： LU Qi WANG Sen SQUIRES Victor YANG Youlin National R ＆ D Centre for Combating Desertification Chinese Academy of Forestry. Beijing 100091 P.R. China canadian forest service natural resources canada 506 west burnside road Victoria BC Canada V8Z 1M5 International Consultant on Dryland PO Box 31 Magill 5072 Adelaide Australina Regional Coordinating Unit United Nations Convention to Combat Desertification Bangkok 10200 Thailand

Desertification and dust storms and their impact on the Chinese economy and the environment were examined. A context was established using the best information available on the trends of desertification and dust storms in China. Building on the context, the second section the root causes of desertification and dust storms were examined. Several myths were sought to be identified about some core issues surrounding desertification and dust storms. China’s National Action Plan to combat desertification was reviewed and the effectiveness of existing strategies and programs for mitigating the adverse effects of desertification and dust storms were discussed. The future research needed was pointed out.

关键词： desertification dust storm impact root cause mitigation strategy