Balancing timber production and habitat conservation of Okinawa Rails(Gallirallus okinawae): Application of a harvest scheduling optimization model in subtropical forest in Okinawa, Japan

Finding the right balance between timber production and the management of forest-dependent wildlife species,present a difficult challenge for forest resource managers and policy makers in Okinawa,Japan.A possible explanation of this can be found in the unique nature of the forest management area which is populated with various kinds of rare and endangered species.This issue has been brought to light as a result of the nomination of northern Okinawa Island in 2018 as a candidate for World Natural Heritage site.The nomination has raised public awareness to the possibility of conflicting management objectives between timber extraction and the conservation of habitat for forest-dependent wildlife species.Managing exclusively for one objective over the other may fail to meet the demand for both forest products and wildlife habitat,ultimately jeopardizing the stability of human and wildlife communities.It is therefore important to achieve a better balance between the objective of timber production and conservation of wildlife habitat.Despite the significance of this subject area,current ongoing discussions on how to effectively manage for forest resources,often lack scientific basis to make sound judgement or evaluate tradeoffs between conflicting objectives.Quantifying the effect of these forest management activities on wildlife habitat provides useful and important information needed to make forest management and policy decisions.In this study we develop a spatial timber harvest scheduling model that incorporates habitat suitability index(HSI)models for the Okinawa Rail(Gallirallus okinawae),an endangered avian species found on Okinawa,Japan.To illustrate how the proposed coupling model assembles spatial information,which ultimately aids the study of forest management effects on wildlife habitat,we apply these models to a forest area in Okinawa and conduct a simple simulation analysis.

North Carolina’s forest disturbance and timber production assessed using time series Landsat observations

Wood products provide a relatively long-term carbon storage mechanism.Due to lack of consistent datasets on these products,however,it is difficult to determine their carbon contents.The main purpose of this study was to quantify forest disturbance and timber product output(TPO)using time series Landsat observations for North Carolina.The results revealed that North Carolina had an average forest disturbance rate of 178,000 ha per year from 1985 to 2010.The derived disturbance products were found to be highly correlated with TPO survey data,explaining up to 87%of the total variance of county level industrial roundwood production.State level TPO estimates derived using the Landsat-based disturbance products tracked those derived from ground-based survey data closely.The TPO modeling approach developed in this study complements the ground-based TPO surveys conducted by the US Forest Service.It allows derivation of TPO estimates for the years that did not have TPO survey data,and may be applicable in other regions or countries where at least some ground-based survey data on timber production are available for model development and dense time series Landsat observations exist for developing annual forest disturbance products.

Characteristic of tradeoffs between timber production and carbon storage for plantation under harvesting impact: A case study of Huitong National Research Station of Forest Ecosystem

The tradeoffs and optimizations of ecosystem services are the key research fields of ecology and geography.It is necessary to maximize the overall benefit of timber production and carbon storage for forest ecological development in China.We selected the Huitong National Research Station of Forest Ecosystem as our study area,and used In VEST model to evaluate timber production and carbon storage quantitatively.The results showed that:(1)While timber production increased with harvesting intensity over the planning horizon,carbon storage decreased.There were tradeoffs between timber production and carbon storage according to the significant negative relationship.(2)While the overall benefit of timber production and carbon storage increased with harvesting intensity,the value of tradeoffs decreased.T1 and T2 scenarios,with harvesting intensity of 10%–20% every 10 years,are the optimum management regimes for the two ecosystem services to gain more benefit and less tradeoffs.(3)The current harvesting intensity in Huitong County was slightly higher than the optimum harvesting intensity.On practical dimension,these findings suggested that obvious objectives are needed to formulate the corresponding countermeasures of tradeoffs,in order to realize the improvement of ecosystem services and the optimization of ecosystem structures.

Population distribution and threats to sustainable management of selected non-timber forest products in tropical lowland rainforests of south western Nigeria

Uncontrolled harvesting of non-timber forest products （NTFPs） poses a serious risk of extermination to several of these species in Nigeria. Yet, there is a paucity of information on the distribution, population status and sustainable management of NTFPs in most of the tropical lowland rainforests. We, therefore, assessed the population, distribution and threats to sustainable management of NTFPs within the tropical lowland rainforests of Omo and Shasha Forest Reserves, south western Nigeria. Data were obtained through inventory surveys on five top priority species including： bush mango （Irvingia gabonensis （Aubry-Lecomte ex O’Rorke） Baill）, African walnut （Tetracarpidium conophorum （Mull. Arg.） Hutch. ＆ Dalziel syn. Plukenetia conophora）, chew-stick （Massularia acuminata （G. Don） Bullock）, fever bark （Annickia chlorantha Setten ＆ P.J.Maas syn. Enantia chloranta） and bush pepper （Piper guineense Schumach. ＆ Thonn.）. Purposive and stratified random sampling techniques were used for the inventory. Each forest reserve was stratified into three, viz： less disturbed natural forest （for areas that have been rested for at least ten years）, recently disturbed natural forest （for areas that have suffered one form of human perturbation or the other in the last five years）, and plantation forest （for areas carrying forest plantation）. Data were collected from eighteen 10 m × 500 m belt transects located in the above strata. The species were generally fewer in both plantation and recently disturbed natural forest than the less disturbed natural forest, suggesting that forest disturbances （habitat modification） for other uses may have an effect on the occurrence and densities of the NTFPs. Exceptions to this trend were found for P. guineense and T. conophorum, which were fairly common in both plantation and recently disturbed natural forest. Among three tree NTFP species （i.e. I. gabonensis, M. acuminata and A. chlorantha）, only I. gabonensis showed a significant difference in overall DBH size classes for both reserves （t=？2.404; df =21; p=0.026）. Three tree NTFP species in both reserves further showed differences from the regular patterns of distribution of trees. The fairly regular reverse J-shaped size class distribution observed for M. acuminata in the study sites, however, suggests a recuperating population. In general, destructive harvesting of species, logging operations, low population size, narrow distribution ranges and habitat degradation are the major threats to the population of NTFPs in the study area. The implications of our findings for sustainable management of NTFPs in the study area are discussed and recommendations are made for a feasible approach towards enhancing the status of the species.

Diversity of non-timber forest products in Cachar District, Assam, India

We identified 67 and 21 NTFP-yielding plant and animal species, respectively, in a reserve forest in Cachar district of Assam. We recorded globally threatened species listed by IUCN as Critically Endangered （plant species Dipterocarpus turbinatus）, Vulnerable （plant species Aquillaria malaccensis）, Endangered （animal species Hoolock hoolock, Indotestudo elongata and Manis pentadactyla）, and Vulnerable （animal species Nilssonia hurum and Rusa unicolor）. The whole plant or animal and/or their various parts were used as food or medicine, in house construction, magico-religious activities and others. While some NTFPs were harvested throughout the year, others were harvested seasonally. A comprehensive NTFP policy, along with scientific measures for regen- eration, restoration and augmentation of NTFP-yielding plants and animals, would help in addressing the conflicting demands of conservation and livelihood in the forests of this area.

Quantification of Ecosystem Services Provided by <i>Pterocarpus lucens</i>Lepr. Ex Guill. and Perrott.: Forage Production, Timber and Carbon Sequestration in the Biosphere Reserve of Ferlo (Northern Senegal)

This study aims at quantifying the most important ecosystem services: forage production, timber production and carbon sequestration provided by Pterocarpus lucens to local communities of Ferlo Biosphere Reserve. The results suggested that the ecological structure of Pterocarpus lucens revealed a bell-shaped form with left dissymmetric distribution indicating a predominance of individuals with small circumference and height. A regression using the software Minitab 16, with circumference and the height as explanatory variables, has allowed a development of predictive models for the estimation of the produced forage and the quantification of the timber supplied by one of the most used plant species in Sahelian pastures. Forage production of Pterocarpus lucens was estimated at 178 kg DM/ha. This large value of forage showed the predominance of this species in animal feed in the Sahel. The quantity of wood produced was 545 kg DM/ha while the quantity of above ground sequestered carbon was 325.35 kg of C/ha. Those estimations are interesting in the implementation context of the Ferlo Biosphere Reserve which aims at matching the productive capacity of ecosystems with the needs of local communities.

Market analysis for timber and forest products in China

This paper introduces the general condition of forestry resources of China and the demand and supply of timber and forest products. The market for timber and forest producls has borne dual pressure because of the population explosion and growth of the domestic economy. A major contemporary strategy for sustainable forestry includes the promotion of the Forest Products Industry (FPI), the substitution of other materials for timber,and the encouragement of imports of timber and forest products. The author analyzes the effect of these policies on the market for timber and forest products. In addition, the difficulties encountered by most mid-to large -scale state- owned forest enterprises during the transition from a centrally-planned economy to a market economy are examined. Finally, the author points out the countermeasures and means for reform of these old forest enterprises with a view toward future prosperity of the market for timber and forest products.

经济林种植户有机肥施用行为及影响因素分析——基于陕西省589户种植户调查数据

在积极倡导环境保护的时代背景下,探讨经济林种植户有机肥施用行为的影响因素,对林业绿色可持续发展具有重要影响。以陕西省589户经济林种植户的调查数据为基础,运用Heckman样本选择模型,着重分析电商参与和社会网络对经济林种植户有机肥施用行为的影响。结果表明,74%的种植户选择施用有机肥,但有机肥投入资金占肥料总投入较低。种植户电商参与、社会网络正向影响其有机肥施用决策和施用程度,并且社会网络在电商参与影响有机肥施用程度的过程中起正向调节作用。此外,家中农用机械数量、经济林种植面积以及是否被评选为科技示范户种植户也会对种植户有机肥施用行为产生影响。

Cost-effectiveness analysis of subsidy schemes for industrial timber development and carbon sequestration in Japanese forest plantations

This study uses simulations to investigate the effects of implementing two different Japanese forestry subsidy systems on timber production and carbon stock, and examines the consequences for harvesting strategies. An existing Local Yield Table Construction System （LYCS）, a wood conversion algorithm, and a harvesting cost model were used in the simulations to test the applicability of different subsidies to the thinning of stands. Using forest inventory data collected by local government staff, simulation output was used to calculate forestry profits, carbon stocks, subsidies, the amount of labor required, and the cost effectiveness of investing in subsidies. By comparing the output of simulations based on two scenarios, we found that both the clear-cutting area and the amount of harvested timber were larger under Scenario 2, in which the rules governing subsidy allocations are more relaxed, than under Scenario 1, in which the rules are more restrictive. Because the harvested timber under Scenario 1 was mainly produced by clear-cutting, the forestry profits and the subsidy predicted in the early period of the simulation, were larger under Scenario 1 than under Scenario 2. In contrast, the carbon stock was larger under Scenario 2 than under Scenario 1. The simulation model is likely to be useful for improving Plan-Do-Check-Act cyclesimplemented in Japanese forest management systems.

受甲虫影响的木材与非木材产品的联合收获策略

基于森林中木材和非木材产品的开发现状,考虑甲虫与森林木材的相互作用关系建立生态数学模型。首先,分析该模型的动力学行为,运用常微分方程的定性理论分析系统平衡点的存在性以及稳定性条件;其次,研究该模型下的最优收获问题,选取收获努力量和对甲虫的人为消杀率为最优控制变量,求出最优解的表达式;最后,结合数值模拟给出具有实际意义的最优收获策略,为林业生态经济的可持续发展提供一定的理论依据。

家居用填充式竹集成材轻量化结构设计

当前木材资源供需矛盾突出,我国丰富的竹资源和日益完善的竹材加工工艺为竹集成材的可持续发展奠定了良好基础。在家居产品中推广使用竹集成材,能够充分利用竹资源,缓解木材供应短缺的问题。但当前,竹集成材产品自重过重问题是制约竹集成材应用的重要因素之一。文章分析了竹集成材的结构及性能以及在家居领域应用的局限性,总结了轻量化设计方法,并以空芯板结构为参考,探讨了竹集成材填充式芯层结构设计。通过采用竹芯层结构减轻竹集成材的自重,能够使竹集成材更广泛地应用在家居生活中,为竹集成材家居产品设计提供创新思路和方法。

Assessing the effects of site factors on the productivity of a feller buncher:a time and motion analysis

We evaluated,for the first time in Turkey,the productivity of a feller buncher during clear-cut operations of two Brutian pine stands located in Canakkale,northwestern Turkey with different diameter classes and terrain conditions.In the first stand with 24.6 cm average DBH,the feller buncher cut full trees and moved them to roadside.In the second stand with 34.3 cm average DBH,the feller buncher cut trees in two stages due to their larger diameters and the relatively steep and rough terrain conditions of the site.The effects of specific stand features,DBH and tree height measurements were assessed through statistical analysis in relation to productivity.The results indicate that the average productivity for the first stand was about 118 m^3h^-1,while it was about 80 m3h-1 in the second stand.Even though tree diameter and volume were higher in the second stand,productivity decreased by32.3%due to extra time spent on the two-stage cutting operation.The results revealed that harvesting operations should be planned carefully and the right equipment selected by accounting for different tree sizes,terrain conditions and machine specifications in order to better understand their effects on production.

Application of Preservative-treated Pinewood in Garden Timber Architecture and Opuscule

Preservative-treated pinewood is mildewproof, anticorrosive and mothproof, with the long durability and environmental protection as its fine performance. It has become an important material for landscape construction for the wide pine material sources, low price, less deformation, moderate density, good fl exibility and strength, fine texture and good integration with the natural environment. On the basis of introducing pinewood species, preservatives and production process of preservative-treated pinewood, this paper focuses on the application of preservative-treated pinewood used in log cabin, pavilion, service buildings and other garden timber architecture, as well as roads, platforms, bridges, rails, gallery frames, pergolas and other opuscules.

全球价值链嵌入、产业集聚对南方十省木材产业全要素生产率的影响

基于内外双循环视角,构建全球价值链嵌入和产业集聚影响木材产业全要素生产率的理论框架,将中国省级层面的区域性投入产出表与全球投入产出表进行匹配,嵌套测算中国南方十省木材产业全球价值链参与度,并实证分析全球价值链嵌入程度和产业集聚水平对全要素生产率的影响机制。结果表明:南方十省木材产业全球价值链参与度水平逐年提升,全球价值链参与度指数每变动1个单位,会对木材产业的全要素生产率产生0.598个单位的正向影响,产业集聚指数每变动1个单位,木材产业全要素生产率会产生0.192个单位的正向变动,提升产业集聚水平对于南方十省木材产业全要素生产率的提升同样具有较为显著的正向作用,这说明已形成一定规模的产业集群,发挥集群优势;全球价值链参与度和产业集聚水平对于提升木材产业全要素生产率具有显著的正向作用,但全球价值链与产业集聚的交互项乘积系数为-0.568,说明全球价值链和产业集聚会构筑壁垒阻碍知识技术的交流从而对全要素生产率的提升产生抑制作用。据此,建议进一步提升十省木材产业全球价值链参与程度和产业集聚水平,促进木材产业全要素生产率的提升、推动产业集群发挥更大的集群效应,结合南方十省实际,出台更多具有针对性的优惠政策,同时完善基础设施建设,共同助力木材产业实现高质量发展。

我国用材林资源状况及木材安全分析

随着我国经济建设持续快速发展,木材刚性需求不断增加,木材安全问题受到广泛关注。基于历次全国森林资源清查结果,对我国用材林资源的权属、起源、龄组、树种等基本情况及分布特点和发展趋势进行了阐述,对我国近70年的木材产量、目前的木材需求及木材安全进行了分析。从建设国家储备林基地、大力培育珍贵用材和大径材、加强森林科学经营、提倡木材节约代用、引导规范木材进口等5个方面,提出了保障木材安全的建议。

俄罗斯森林资源与木材生产分析

根据俄罗斯森林资源与木材生产发展状况,探讨了俄罗斯森林资源的特点,总结了俄罗斯木材生产面临的主要问题,提出了俄罗斯林产品的品种和产量走势,分析了俄罗斯森工行业和木材生产的发展机遇,展望了中俄森林资源合作开发与林产品贸易和林业双边合作的发展前景。

我国森林资源木材生产能力预测分析

根据1949—2020年我国木材产量数据,运用多项式回归方法,预测了2021—2030年我国木材产量。结果显示,我国可在2025—2029年期间实现木材供给从以国际市场供给为主体到以国内市场供给为主体的转换。利用全国森林资源清查数据,从森林资源消长平衡的角度分析发现,在目前的森林资源条件下,我国已具备主要依靠国内森林资源供给木材的条件,我国未来的森林资源发展也可支撑预测的到2029年以前木材产量增长。

择伐对阔叶红松林资源可持续利用的影响

科学评估目前的择伐方式对森林结构与功能的影响对区域森林资源的可持续利用具有重要意义。以择伐过的阔叶红松林为研究对象,并以原始林为对照,分析了择伐对物种组成、林分结构以及对木材生产的影响。结果表明,低强度择伐(≤20%)对物种组成和蓄积结构均没有显著影响,而高强度择伐则显著改变了物种组成和蓄积结构。择伐后林分蓄积量均显著小于原始林,不同择伐强度间没有显著差异。择伐显著影响了用材树种的数量和质量,导致择伐后样地中用材树种的株数和蓄积量均显著减少,严重影响了林分的木材持续生产能力。因此,从阔叶红松林木材可持续利用角度来看,需要重新思考红松不作为采伐树种的用材林经营技术模式。

兼顾碳贮量和木材生产目标的森林经营规划研究

以吉林省汪清林业局金沟岭林场为对象,基于小班调查数据,以木材生产和碳增量净现值最大为规划目标,考虑采伐量不大于生长量、均衡采伐、生长模型等约束,建立了多目标规划模型。通过LINGO软件求解,得到了50a规划期的最优经营方案,并进行了灵敏度分析。结果表明:各个森林类型在不同分期间伐强度在1%～15%之间,择伐强度在1%～35%之间。规划期木材总采伐量为182.33万m3,规划期末地上碳贮增量为47.92万t;规划期总收益为95 434.40万元,其中木材净现值91 895.10万元,碳贮增量净现值3 539.30万元。多目标经营方案可以同时满足对木材生产和碳贮增量的需求,是一个折衷的方案。与木材生产经营方案相比,多目标经营方案和碳贮增量经营方案在规划期内的木材净现值分别减少2.67%、45.43%,但地上碳贮增量净现值分别增加29.88%、50.42%。因此增加碳贮增量要以减少木材采伐量为代价。分析了低、中、高3种碳价格对多目标经营方案的影响,表明整个规划期内木材采伐量随着碳价格的增加而减少,而碳贮增量随着碳价格的增加而增加。

基于行业标准的木材生产作业系统碳排放

以现行林业行业标准为基础,核算标准工序下木材生产的综合能耗量,并以此计算木材生产作业系统的温室气体排放量.结果表明：在基本条件下机械化木材生产的碳排放在9.4050~12.3488 kg/m3,其中木材运材碳排放最大,约占65.3%~74.7%；其次为集材段（拖拉机占12.2%~15.7%,索道占11.0%~14.3%）；碳排放作业过程还受气温、海拔及林型、蓄积量等的影响,尤其是采伐工序,平均条件下的油锯采伐碳排放是基本条件下的2.22倍.虽然木材运输在平均条件下的碳排放是基本条件的1.5倍,但由于木材运输阶段所占的排放比例最大,因此在实际生产中,提高车辆的使用率与尾气排放技术对降低木材生产的碳排放具有重大意义；从碳排放角度看,油锯采伐—索道集材—绞盘机装车—柴油车运材—水运到材为最优作业模式.研究结果可为森工作业过程中合理选择木材生产作业方式提供科学依据.