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Journal of forestry Research 2017年第5期28卷 1049-1059页

作者： Róbert Smreek Ivan Sakov Zuzana Michnová Ján Tuek department of forest Management and Geodesy Technical University in Zvolen department of forest Policy Economics and Forest ManagementNational Forest Centre-Forest Research Institute Zvolen

Identifying tree locations is a basic step in the derivation of other tree parameters using remote sensing techniques, particularly when using airborne laser scanning. There are several techniques for identifying tree positions. In this paper, we present a raster-based method for determining tree position and delineating crown coverage. We collected data from nine research plots that supported different mixes of species. We applied a raster-based method to raster layers with six different spatial resolutions and used terrestrial measurement data as reference data. Tree identification at a spatial resolution of 1.5 m was demonstrated to be the most accurate, with an average identification ratio (IR) of 95% and average detection ratio of 68% being observed. At a higher spatial resolution of 0.5 m, IR was overestimated by more than 600%. At a lower spatial resolution of 3 m, IR was underestimated at less than 44% of terrestrial measurements. The inventory process was timed to enable evaluation of the time efficiency of automatic methods.

关键词： Airborne laser scanning East-Central Europe Individual tree Mixed forest Tree crown delineation

Soil fixation and erosion control by Haloxylon persicum roots in arid lands, Iran

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Journal of Arid Land 2019年第1期11卷 86-96页

作者： Ehsan ABDI Hamid R SALEH Baris MAJNONIAN Azade DELJOUEI department of forestry and forest economics Faculty of Natural Resources University of Tehran

Vegetation roots contribute to soil fixation and reinforcement, thus improving soil resistance against erosion. Generally, the amount of soil fixation presented by roots mainly depends on root density and tensile strength. In the present study, we conducted the research in order to further understand the biotechnical properties of Haloxylon persicum and also to quantify its role in increasing soil cohesion in arid lands of Iran. Ten H. persicum shrubs were randomly selected for root distribution and strength investigations, in which five samples were set on flat terrain and other five samples on a moderate slope terrain. The profile trench method was used to assess the root area ratio(RAR) as the index of root density and distribution. Two profiles were dug around each sample, up and downslope for sloped treatment and north and south sides for flat treatment. The results showed that RAR increased with increasing soil depth and significantly decreased in 40–50 cm layers of downhill(0.320%) and 50–60 cm for uphill(0.210%). The minimum values for the northward and southward profiles were 0.003% and 0.003%, respectively, while the maximum values were 0.260% and 0.040%, respectively. The relationship between the diameter of root samples and root tensile strength followed a negative power function, but tensile force increased with increasing root diameter following a positive power function. The pattern of increased cohesion changes in soil profile was relatively similar to RAR curves. The maximum increased cohesion due to the presence of roots in uphill and downhill sides were 0.470 and 1.400 kPa, respectively. In the flat treatment, the maximum increased cohesions were 0.570 and 0.610 kPa in northward and southward profiles, respectively. The analysis of variance showed that wind and slope induced stresses did not have any significant effect on the amount of increased cohesion of H. persicum. The findings served to develop knowledge about biotechnical properties of H. p

关键词： biotechnical properties increased soil cohesion profile trench method root area ratio (RAR) tensile strength

Effects of soil compaction on growth variables in Cappadocian maple(Acer cappadocicum) seedlings

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Journal of forestry Research 2018年第3期29卷 599-608页

作者： Meghdad Jourgholami department of forestry and forest economics Faculty of Natural Resources University of Tehran

This study investigates the effects of increasing soil penetration resistance(SPR) on seedling morphology and seedling architecture. When seedlings of deciduous Cappadocian maple(Acer cappadocicum Gled.) were grown in a greenhouse in a loamy soil under a wide range of soil compactions, all morphological variables studied changed significantly with increasing SPR. The relationships between increasing SPR and all morphological responses except lateral root length followed a negative quadratic curve. All biomass variables except lateral root biomass showed a bell-shaped response with respect to SPR, with a maximum biomass variable between 0.6 and1.2 MPa, decreasing at higher soil compaction values. All allocation ratios were significantly affected by soil penetration resistance. Biomass allocation to roots was also affected by soil compaction. There was not a significant relationship between the specific stem length and increasing soil penetration resistance. The specific root length showed two trends to increasing SPR; it first decreased in response to the moderate compaction treatment(up to about 1.2 MPa), then increased significantly. We concluded that increasing soil compaction caused morphological changes to root and shoot sections of *** seedlings.

关键词： Soil penetration resistance Cappadocian maple Morphology Biomass Allocation ratios

Valuation of forest carbon sinks in China within the framework of the system of national accounts

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Journal of forestry Research 2016年第6期27卷 1321-1328页

作者： Ying Zhang Jiancheng Chen Mingxing Hu Armin Offer School of economics and Management Beijing Forestry University department of forest Valuation State Forest Enterprise Hessen-Forst

To better promote forest resource management and strengthen the development of forest carbon sink marketization, this paper studied the accounting of forest carbon sinks from 2003 to 2008 based on a system of national accounts （SNA） and data from the latest forest resources inventory in China. The study calculated the value of forest carbon stocks at a total of RMB 817.13 × 10^9 yuan in 2003 and RMB 839.93×10^9 yuan in 2008, with an average annual increase of 0.55 % from an increase in physical carbon sinks. The total value of forest carbon sinks in 2003 and 2008 was RMB 26.73×10^9 yuan and RMB 29.77×10^9 yuan, respectively, with an average annual growth of 2.18 %. From 2003 to 2008, both stock and flow value of forest carbon sinks increased, but the total net flow value of carbon sinks decreased. The growth rate for the environmentally adjusted Gross Domestic Product （eaGDP） for China＇s forest carbon sinks was 17.23 %, outstripping the average growth rate of 9.5 % for the GDP during the same period. The study alsoindicates that China＇s forest carbon sinks affects the GDP in the range of 0.25-0.26 %, and its economic potential is not relatively huge.

关键词： Carbon sequestration market China Economic development System of national accounts Valuation

Role of copper chelating agents: between old applications and new perspectives in neuroscience

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Neural Regeneration Research 2025年第3期20卷 751-762页

作者： Rosalba Leuci Leonardo Brunetti Vincenzo Tufarelli Marco Cerini Marco Paparella Nikola Puvača Luca Piemontese department of Pharmacy-Pharmaceutical Science University of Bari Aldo MoroBariItaly department of Precision and Regenerative Medicine and Jonian Area(DiMePRe-J) Section of Veterinary Science and Animal ProductionUniversity of Bari Aldo MoroBariItaly department of Engineering Management in Biotechnology Faculty of Economics and Engineering Management in Novi SadUniversity Business Academy in Novi SadNovi SadSerbia

The role of copper element has been an increasingly relevant topic in recent years in the fields of human and animal health, for both the study of new drugs and innovative food and feed supplements. This metal plays an important role in the central nervous system, where it is associated with glutamatergic signaling, and it is widely involved in inflammatory processes. Thus, diseases involving copper(Ⅱ) dyshomeostasis often have neurological symptoms, as exemplified by Alzheimer's and other diseases(such as Parkinson's and Wilson's diseases). Moreover, imbalanced copper ion concentrations have also been associated with diabetes and certain types of cancer, including glioma. In this paper, we propose a comprehensive overview of recent results that show the importance of these metal ions in several pathologies, mainly Alzheimer's disease, through the lens of the development and use of copper chelators as research compounds and potential therapeutics if included in multi-target hybrid drugs. Seeing how copper homeostasis is important for the well-being of animals as well as humans, we shortly describe the state of the art regarding the effects of copper and its chelators in agriculture, livestock rearing, and aquaculture, as ingredients for the formulation of feed supplements as well as to prevent the effects of pollution on animal productions.

关键词： agriculture Alzheimer's disease chelators copper feed supplements multi-target

Traditional mule logging method in Hyrcanian forest: a study of the impact on forest stand and soil

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Journal of forestry Research 2013年第4期24卷 755-758页

作者： Meghdad Jourgholami Baris Majnounian department of forestry and forest economics Faculty of Natural ResourcesUniversity of Tehran

We inventoried plant regeneration and soil compaction along mule trails to evaluate damage to forest stands and regeneration follow- ing mule hauling before and after operations in Kheyrud forest in the Hyrcanian forest in northern Iran. About 22% of regenerating plants on mule trails were damaged following mule logging, and damage to trees was observed. In harvested units after timber extraction, 4.3% of the total area （12 ha） was covered with mule trails. Mule passes and slope gradi- ent, and twofold interactions between mule passes x slope gradient had no significant effect on soil bulk density （p 〈 0,05）. Mule iogging had a statistically significant effect on soil bulk density along the mule trails before and after mule passes. Soil bulk density increased Significantly as mule passes increased in number. The degree and level of compaction did not differ with trail slope. With respect to damage to residual stands and seedlings, soil compaction and disturbance to soil, traditional mule log- ging is the preferred skidding method in the steep terrain conditions in the Hyrcanian forest in northern Iran.

关键词： Mule logging stand damage seedling soil compaction

An integrated assessment approach to optimal forest bioenergy production for young Scots pine stands

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forest Ecosystems 2015年第3期2卷 220-229页

作者： Tianjian Cao Kari Hyytiainen Henna Hurttala Lauri Valsta Jerome K.Vanclay College of forestry Northwest A&F University department of economics and Management University of Helsinki department of forest Sciences forest Research Centre Southern Cross University

Background: Bioenergy is re-shaping opportunities and imperatives of forest management. This study demonstrates,through a case study in Scots pine(Pinus sylvestris L.), how forest bioenergy policies affect stand management ***: Optimization studies were examined for 15 Scots pine stands of different initial stand densities, site types, and temperature sum regions in Finland. Stand development was model ed using the Pipe Qual stand simulator coupled with the simulation-optimization tool Opti For Bioenergy to assess three forest bioenergy policies on energy wood harvest from early ***: The optimal solutions maximizing bare land value indicate that conventional forest management regimes remain optimal for sparse stands. Energy harvests occurred only when profitable, led to lower financial returns. A forest bioenergy policy which included compulsory energy wood harvesting was optimal for denser stands. At a higher interest rate(4 %), increasing energy wood price postponed energy wood harvesting. In addition, our results show that early thinning somewhat reduced wood quality for stands in fertile sites. For less fertile sites, the changes were ***: A constraint of profitable energy wood harvest is not rational. It is optimal to carry out the first thinning with a flexible forest bioenergy policy depending on stand density.

关键词： Energy wood Policy design Precommercial thinning Scots pine Simulation-optimization

Concept of the integrative aspects of the forest ecosystem services with case study on recreation services assessment in Slovakia

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Ecological Processes 2014年第1期3卷 136-141页

作者： Vladimir Caboun Miroslav Kovalcik Zuzana Sarvasova department of forest Ecology and Landscape National Forest Centre-Forest Research Institute ZvolenT.G.Masaryka 22ZvolenSK-96092Slovakia department of forest Policy Economics and Forest ManagementNational Forest Centre-Forest Research Institute ZvolenT.G.Masaryka 22SK-96092 ZvolenSlovakia

Introduction:This paper presents basic information on the research,classification,and application of the functions of tree species and their communities(mainly forest)in *** main aim is a scientific assessment of acquired knowledge regarding the functional effects of forests under real ecological,forest management and socio-economic conditions from various regions in Slovakia;the most up-to-date findings concerning the ecology and economics of natural resources will be applied *** second part of the paper presents methodological possibilities for valuation of outdoor recreation in *** methods and methodological approaches suitable to a valuation of recreation based on various principles and criteria(preference and non-preference methods,cost-based methods,revenue-based methods,and direct and indirect methods)are analyzed.A practical application of one indirect preference method(travel cost method)is made to evaluate outdoor recreation in forests in *** and conclusions:A new classification system and a methodology of integrative utilization of forest functions for the forest ecosystem services are *** recreation in forests,besides recreational forests and areas,assumes the character of a public good:its use by individuals has some influence on utilization by other individuals,and single users cannot be excluded from its ***,some stimulation for its production is *** principle,there are no markets for these kinds of public goods and *** total value of outdoor recreation in forests in Slovakia amounted to€163.4 million;if opportunity time costs were included,this amounted to as much as€825.7 million.

关键词： Classification of forest functions forest functions Outdoor recreation in forests Utilization of the functions of forest tree species

Forecasting volatility in oil prices with a class of nonlinear volatility models:smooth transition RBF and MLP neural networks augmented GARCH approach

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Petroleum Science 2015年第3期12卷 534-552页

作者： Melike Bildirici zgÖrü Ersin department of economics Yildiz Technical University department of economics Beykent University

In this study, the forecasting capabilities of a new class of nonlinear econometric models, namely, the LSTAR-LST-GARCH-RBF and MLP models are evalu- ated. The models are utilized to model and to forecast the daily returns of crude oil prices. Many financial time series are subjected to leptokurtic distribution, heavy tails, and nonlinear conditional volatility. This characteristic feature leads to deterioration in the forecast capabilities of tradi- tional models such as the ARCH and GARCH models. According to the empirical findings, the oil prices and their daily returns could be classified as possessing nonlinearity in the conditional mean and conditional variance processes. Several model groups are evaluated：（i） the models pro- posed in the first group are the LSTAR-LST-GARCH models that are augmented with fractional integration and asymmetric power terms （FIGARCH, APGARCH, and FIAPGARCH）; （ii） the models proposed in the second group are the LSTAR-LST-GARCH models further aug- mented with MLP and RBF type neural networks. The models are compared in terms of MSE, RMSE, and MAE criteria for in-sample and out-of-sample forecast capabili- ties. The results show that the LSTAR based and neural network augmented models provide important gains over the single-regime baseline GARCH models, followed by the LSTAR-LST-GARCH type models in terms of mod- eling and forecasting volatility in crude oil prices.

关键词： Volatility Petrol prices ARCH STAR Neural networks LSTAR-LST-GARCH family

Changing structure of China's meat imports

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Journal of Integrative Agriculture 2015年第6期14卷 1081-1091页

作者： CHENG Ya-hao Zhifeng Gao James Seale Jr. department of economics Nankai University Food and Resource economics department University of Florida

This paper discusses the determinants of meat imports of China. Results indicate that import demand is mostly determined by import price and real GDP. Imported price has a negative effect and real GDP has a positive influence on import quantity. Tariff does not have a significant effect. As GDP and consumption capacity increases, China has a large potential demand for meat imports. Some countries may gain if China＇s economy continues expanding, while others, like the United States, are the most sensitive to the trade policy of China.

关键词： imports Zealand expanding Australia income prices capita Fresh mostly accounting