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Forests,atmospheric water and an uncertain future: the new biology of the global water cycle

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Forest Ecosystems 2018年第3期5卷 236-257页

作者： Douglas Sheil faculty of Environmental Sciences and natural resource Management(MINA) Norwegian University of Life Sciences (NMBU)

Theory and evidence indicate that trees and other vegetation influence the atmospheric water-cycle in various *** influences are more important, more complex, and more poorly characterised than is widely *** there is little doubt that changes in tree cover will impact the water-cycle, the wider consequences remain difficult to predict as the underlying relationships and processes remain poorly characterised. Nonetheless, as forests are vulnerable to human activities, these linked aspects of the water-cycle are also at risk and the potential consequences of large scale forest loss are severe. Here, for non-specialist readers, I review our knowledge of the links between vegetation-cover and climate with a focus on forests and rain(precipitation). I highlight advances, uncertainties and research opportunities. There are significant shortcomings in our understanding of the atmospheric hydrological cycle and of its representation in climate models. A better understanding of the role of vegetation and tree-cover wil reduce some of these shortcomings. I outline and il ustrate various research themes where these advances may be *** themes include the biology of evaporation, aerosols and atmospheric motion, as well as the processes that determine monsoons and diurnal precipitation cycles. A novel theory—the ‘biotic pump’—suggests that evaporation and condensation can exert a major influence over atmospheric dynamics. This theory explains how high rainfall can be maintained within those continental land-masses that are sufficiently forested. Feedbacks within many of these processes can result in non-linear behaviours and the potential for dramatic changes as a result of forest loss(or gain): for example, switching from a wet to a dry local climate(or visa-versa). Much remains unknown and multiple research disciplines are needed to address this: forest scientists and other biologists have a major role to *** ideas, methods and data offer opportun

关键词： Biotic pump Climate Condensation Evaporation Ice-nucleation Transpiration GCM Vapour Water-cycle

Sediment contribution from different geologic formations and land uses in an Iranian small watershed,case study

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International Journal of Sediment Research 2017年第2期32卷 210-220页

作者： Seyed Hamidreza Sadeghi Saeed Najafi Alireza Riyahi Bakhtiari Department of Watershed Management Engineering Faculty of Natural ResourcesTarbiat Modares University Department of Environmental Sciences Faculty of Natural ResourceTarbiat Modares University

Many intra and extra problems occurred due to unsustainable human use of natural resources leading to increasing sediment loads in the ***,few studies have been comprehensively conducted in progressing countries to prioritize sediment sources from different points of views,particularly in some countries like Iran where such valuable information is essential for proper watershed resources *** present study was therefore planned to assess the importance of potential sediment sources viz.,spatial sources(geologic units) and source types(land use units) in sediment yield in Idelo watershed as one of the important sub-watersheds of Sefidrood large Watershed in Zanjan Province,Iran,using composite *** addition,the results of the sediment fingerprinting approach were compared with those of field measurement data obtained from studying soil erosion types(viz.,sheet,rill and gully erosion).Toward this attempt,16 tracers were detected in different geologic units and land uses and the sediment yielded at the watershed *** results showed that the composite fingerprints of the different geologic units comprising As,N,Cu,Zn,OC and Co tracers could correctly distinguish 86% of the sediment source *** red gypsiferous marl contributed 85 percent in sediment *** regard to source types,the optimum composite fingerprint encompassed only N and Cu and provided a discriminatory efficiency of 90%.Besides that,the rangelands with 48.8% study area coverage had a significant contribution of 88% in sediment *** field measurements confirmed the reliability of results of fingerprinting approach in apportioning watershed scale sediment sources on the base of consistency of the two sets of *** was also understood from the results,besides successful applicability of composite fingerprinting in assessing the provenance of the sediment yielded at the watershed outlet that the geologic formations and land use types played differe

关键词： Composite fingerprinting Multivariate mixing model Soil erosion Spatial sources Source types

Mixed-effects modeling for tree height prediction models of Oriental beech in the Hyrcanian forests

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Journal of Forestry Research 2018年第5期29卷 1195-1204页

作者： Siavash Kalbi Asghar Fallah Pete Bettinger Shaban Shataee Rassoul Yousefpour Sari Agriculture and natural resource University SariMazandaran Iran Warnell School of Forestry and natural resources University of Georgia Athens GA USA Gorgan Agriculture and natural resource University Gorgan Golestan Iran faculty of Environment and natural resources University of Freiburg Freiburg Germany

Height–diameter relationships are essential elements of forest assessment and modeling *** this work,two linear and eighteen nonlinear height–diameter equations were evaluated to find a local model for Oriental beech（Fagus orientalis Lipsky） in the Hyrcanian Forest in *** predictive performance of these models was first assessed by different evaluation criteria： adjusted R^2（R^2_（adj））,root mean square error（RMSE）,relative RMSE（%RMSE）,bias,and relative bias（%bias） *** best model was selected for use as the base mixed-effects *** parameters for test plots were estimated with different tree selection *** show that the Chapman–Richards model had better predictive ability in terms of adj R^2（0.81）,RMSE（3.7 m）,%RMSE（12.9）,bias（0.8）,%Bias（2.79） than the other ***,the calibration response,based on a selection of four trees from the sample plots,resulted in a reduction percentage for bias and RMSE of about 1.6–2.7%.Our results indicate that the calibrated model produced the most accurate results.

关键词： Random effects Tree height Calibration Sangdeh forest Chapman–Richards model Oriental beech

Distribution and genesis of secondary pores in Paleogene clastic reservoirs of Beidagang structural belt in the Huanghua depression

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Mining Science and Technology 2010年第1期20卷 115-120页

作者： SU Nina, JIN Zhenkui, SONG Fan faculty of natural resource and Information Technology, China University of Petroleum, Beijing 102249, China [a] faculty of natural resource Information Technology China University of Petroleum Beijing 102249 China

The distribution and genesis of secondary pores in Paleogene clastic reservoirs of Beidagang structural belt in the Huanghua depression have been systematically studied. We investigated sedimentary facies and carried out a comprehensive analy-sis of the vast amount of data from casting thin sections, scanning electron microscope and physical data. Then we analyzed the pore types, pore evolution, distribution and genesis of secondary pores in our study area and discussed the factors controlling the distribution of secondary pores. The results show that pores in the study area are largely composed of intergranular dissolution pores and constituent dissolved pores. Three secondary pore zones were developed in the study area at depths of 2800~3400 m, 3600~4200 m and 4500~4800 m. Secondary pores have been formed mainly because carbonate cement, feldspar, clastic debris and other plastic substances were dissolved by organic acid, released during the evolution of organic matter and acid water formed by CO2. The development and distribution of secondary pores are vertically controlled by the maturity time of source rocks and hori-zontally by the distribution of acid water. As well, this distribution was affected by the sedimentary facies belt and the development of fault zones.

关键词： Huanghua depression Beidagang structural belt Paleogene clastic reservoirs secondary pores controlling factor

Estimation of conservation value of myrtle(Myrtus communis)using a contingent valuation method:a case study in a Dooreh forest area,Lorestan Province,Iran

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Forest Ecosystems 2016年第1期3卷 26-36页

作者： Neda Amiri Seyed F.Emadian Asghar Fallah Kamran Adeli Hamid Amirnejad department of forestry sari agricultural and natural resource universitySariIran department of forest sciences gorgan agricultural and natural resource universityGorganlran department of forestry college of natural resourcessari agricultural sciences and natural resources universitySariIran department of forestry faculty of agriculturaluniversity of lorestanlorestanIran department of agricultural economics sari agricultural and natural resource universitySariIran

Background： Around 2000 plant species occur naturally in Lorestan Province of which 250 species are medicinal and myrtle is one of them. Myrtle is a shrub whose leaves and fruits have medicinal value and thus, if managed and harvested properly, could produce sustained economic benefits. In recent years, however, over half of the myrtle site areas was destroyed, due to inappropriate management and excessive harvesting practices. Thus, coming up with a practical harvesting approach along with identifying those factors damaging the sites, seems to be very crucial. Methods： In our investigation, we calculated the conservation value per hectare of myrtle in the Dooreh forest area in Lorestan Province. Using the Contingent Valuation （CV） and Double Bounded Dichotomous Choice （DBDC） methods, we determined the willingness to pay （VVTP） for myrtle conservation. The VVTP was estimated with a Iogit model for which indices were obtained based on a maximum precision criterion. Results： The results showed that 86.67 per cent of people were willing to pay for the conservation of these myrtle sites. Average monthly WTP per family was calculated as $0.79. The annual conservation value in terms of WTP for the preservation of the myrtle sites in Dooreh was estimated as $102,525. Among the variables of the model presented, education had a positive impact, while the amount proposed for payment and family size had a negative impact on the WTP. Conclusions： Our estimate of the value of myrtle conservation should provide justification for policy makers and decision making bodies of natural resources to implement policies in order to conserve the natural sites of this species more effectively.

关键词： Conservation value Myrtle Contingent valuation method Double Bounded Dichotomous method Logit model

Effects of mechanical activation on the structural changes and microstructural characteristics of the components of ferruginous quartzite beneficiation tailings

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International Journal of Mining Science and Technology 2016年第6期26卷 1043-1049页

作者： Ermolovich E.A. Ermolovich O.V. faculty of Mining and natural resource Management Belgorod State National Research University Geo Stroy Monitoring Bel GU LTD

The effects of mechanical activation in a planetary mill on the structural changes and microstructural characteristics of the components of ferruginous quartzite beneficiation railings generated by wet magnetic separation process were studied using X-ray and laser diffraction methods. The results revealed the relationship between variations in the mean particle size of activated powders and the milling time. The crystallite size, microstrain, lattice parameters and unit cell volumes were determined for different milling times in powder samples of quartz, hematite, dolomite, and magnetite from the beneficiation tailings. The main trends in the variation of the crystallite size of quartz, hematite, dolomite, and magnetite as a function mean particle size of powder samples were revealed. Changes in the particle shape as a function of the activation time was also investigated.

关键词： Ferruginous quartzite beneficiation tailings Mechanical activation Crystallites Planetary mill Microstructure Structural changes

Wild pistachio tree (Pistacia mutica) in the Qalajeh forest region of western Iran

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Journal of Forestry Research 2013年第3期24卷 611-614页

作者： Mohsen Javanmiri Pour Mousa Rasouli Hamid Soofi Mariv Mohammad Avatefi Hemat Masood Shahmoradi natural resource faculty Tehran University Karaj Iran. Landscape Engineering Department Faculty of Natural Resources andEnvironment Malayer University Malayer Iran. Department of Horticulture Science Agriculture Faculty Guilan UniversityRasht Iran.

Wild pistachio tree （Pistacia mutica） is considered the most important species in the Zagros forests. It can adapt to unfavorable environmental conditions. To find the suitable ecological conditions for pistachio species, we investigated different environmental factors such as gradient, aspect and position of the slopes through the distribution area. Frequency of pistachio trees in the north and northwest of Qalajeh forests was 36.4% and 1%, respectively. Maximum （32%） and minimum （13%） number of wild pistachio trees were in 30%--60% and 〉120% slope classes, respectively. The most number and least number of pistachio trees were found at elevations of 1100-1200 m and 2200-2300 m, respectively. The percentage of pistachio canopy coverage was 10. The average percentage of herbaceous coverage was 6.5. Pistachio trees of diameter per hectare at breast height （DBH）〉20 cm numbered 5 while average number of pistachio trees was 8 per hectare. Pistachio seedlings per hectare averaged 3.5. The number of other species per ha was 7 trees. The effect of aspect on other species was not significant （p=0.151）. Slope class and geographical aspect did not affect regeneration （p=0.275 and p=0.111, respectively）. Pistachio plays an important economic role in semi-arid areas, therefore it is essential to protect and restore Qalajeh forests through participation by government and local people.

关键词： quantitative investigation quality coverage percentage Qalajeh habitat Pistacia mutica

Cross-specific amplification of microsatellite DNA markers in Shorea platyclados

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Journal of Forestry Research 2016年第1期27卷 27-32页

作者： Asif J.Muhammad Charles H.Cannon Wickneswari Ratnam Department of Biological Sciences Texas Tech University faculty of Science and Technology School of Environmental and Natural Resource SciencesUniversiti Kebangsaan Malaysia

In the megadiverse forests of Southeast Asia, hundreds of timber species are economically important but the population genetics of only a few taxa are known. Cross-specific amplification of microsatellite loci among closely related taxa could enhance our ability to study and manage previously unstudied species. We successfully utilized STMS markers in Shorea platyclados, originally developed for Shorea curtisii. The six primer pairs we tried successfully produced PCR products of expected sizes. The number of alleles observed ranged from 10 to 14 and an average of 12 alleles were detected per locus. A high expected and observed heterozygosity was observed and it ranges from 0.718 to 0.827 among all populations across all six loci tested. Microsatellite DNA markers are highly polymorphic, co-dominant, reproducible, and amenable to high throughput genetic analyses. Overall, the cross- specific amplification of microsatellite loci appears to be complicated by numerous factors. While the approach may be effective for local management and conservation ofpoorly known species, the results must be carefully interpreted.

关键词： Genetic marker systems Populationgenetics SSR Selective logging Tropical timber Capillary electrophoresis

Characterization of mean stem density,fibre length and lignin from two Acacia species and their hybrid

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Journal of Forestry Research 2018年第2期29卷 540-546页

作者： Asif Javed Muhammad Seong Siang Ong Wickneswari Ratnam School of Environmental and natural resource Sciences Faculty of Science and TechnologyUniversiti Kebangsaan Department of Forestry and Range Management University of Agriculture Faisalabad

The objective of this study was to compare the wood properties related to wood pulp quality of two widely planted Acacia species *** mangium *** Acacia auriculiformis *** *** their *** insoluble lignin content(Klason),mean stem density and fibre length differed considerably among the species and *** possessed a high percent of lignin content compared to *** and the Acacia ***,mean stem density of *** was higher than *** and the *** length of heartwood tissues was generally shorter than that of sapwood *** hybrid had longer fibres than the parent *** was negatively correlated with mean stem ***,the wood properties of the hybrid were superior to its parent *** significant intraspecific variation observed for wood properties of Acacia species could be used in breeding superior hybrids combining desirable traits of the two *** thedifficulty involved in accurately measuring the lignin content compared to mean stem density,selection for plants with low lignin content can be achieved by indirect selection of high mean stem density.

关键词： Acacia mangium × Acacia auriculiformis hybrid Fibre length Indirect selection Lignin content Mean stem density