甘肃省河西内陆河流域荒漠化综合防治（I）

（1）河西内陆河流域属于典型的干旱荒漠气候，水资源十分缺乏。水资源是河西内陆河流域荒漠化众多因子中的主导因子，控制水资源的开采量和合理利用水资源是河西内陆河流域荒漠化防治的关键。（2）要解决河西内陆河流域的荒漠化问题就必须首先解决当地群众的生活问题，要解决当地群众的生活问题，就必须首先解决荒漠化问题，二者互为前提。（3）解决河西内陆河流域生态环境保护与经济发展矛盾的原则应该就地挖潜、就地消化，而不应该将人口和经济发展对于环境的压力向外转移。解决生态环境保护和群众生活的根本出路在于挖掘科技与管理的潜力。（4）河西内陆河流域荒漠化综合防治第一层面的工作是首先将一部分对于生态资源的压力转移到依靠非生态资源方面去；第二个层面的工作是制定荒漠化综合防治总目标和流域配水方案及用水限额方案；第三个层面的工作是寻求解决群众生活问题的出路即提高生态资源利用效益的途径；第四层面的工作是在内陆河流域全面实施荒漠化综合防治方案。第五层面的工作是实现生态资源的集约经营。（5）以生态环境建设控制指标为下限约束条件、以最小成本为投资目标，以生态环境建设措施为决策变量，建立生态环境建设优化模型；以生态资源保护指标为上限约束条件、以最大产值为效益目标，以资源开发措施为决策变量，建立生态经济优化模型，既可以有效防治荒漠化，又能在保护生态资源和建设生态环境的前提下最大限度地发展经济。（6）生态经济优化模型适宜采用经济担保的方式建立若干个推广示范农户先行示范；农户普遍接受生态经济优化模型是实行用水限额管理的前提；用水限额可按注册耕地面积或人口分配管理。（7）河西内陆河流域的荒漠化，尤其是近50a来荒漠化过程的加剧，主要是人为因素造成的；将荒漠化的人为因素划分为社会性人为因素和纯人为因素具有管理学意义；纯人为因素主要是管理机关和管理部门在管理方面的不作为行为；要实现河西内陆河流域荒漠化防治的有效性，就必须把严格管理贯穿于荒漠化防治的全过程。     

甘肃省河西内陆河流域荒漠化综合防治(Ⅰ)

(1)河西内陆河流域属于典型的干旱荒漠气候,水资源十分缺乏。水资源是河西内陆河流域荒漠化众多因子中的主导因子,控制水资源的开采量和合理利用水资源是河西内陆河流域荒漠化防治的关键。(2)要解决河西内陆河流域的荒漠化问题就必须首先解决当地群众的生活问题,要解决当地群众的生活问题,就必须首先解决荒漠化问题,二者互为前提。(3)解决河西内陆河流域生态环境保护与经济发展矛盾的原则应该就地挖潜、就地消化,而不应该将人口和经济发展对于环境的压力向外转移。解决生态环境保护和群众生活的根本出路在于挖掘科技与管理的潜力。(4)河西内陆河流域荒漠化综合防治第一层面的工作是首先将一部分对于生态资源的压力转移到依靠非生态资源方面去;第二个层面的工作是制定荒漠化综合防治总目标和流域配水方案及用水限额方案;第三个层面的工作是寻求解决群众生活问题的出路即提高生态资源利用效益的途径;第四层面的工作是在内陆河流域全面实施荒漠化综合防治方案。第五层面的工作是实现生态资源的集约经营。(5)以生态环境建设控制指标为下限约束条件、以最小成本为投资目标,以生态环境建设措施为决策变量,建立生态环境建设优化模型;以生态资源保护指标为上限约束条件、以最大产值为效益目标,以资源开发措施为?     

Key Strategies Against Desertification in China

本文首先介绍了中国土地荒漠化现状及其成因．提出了中国在防治荒漠化工作中所采取的主要战略措施，其中包括：（１）通过大众传媒加强荒漠化防治的宣传与教育力度；（２）加强法制教育和执法力度，进一步完善各项法律、法规；（３）通过加强先进科学技术推广与人员培训，促进荒漠化防治工作、巩固成效；（４）制定优先政策，加大投资力度，促进荒漠化防治工作的大力发展．最后，本文介绍了中国荒漠化防治的最新进展．     

张掖市荒漠化土地治理对策探讨

针对引起荒漠化土地加剧发展的人为因素，从人类生态观构建、政府决策、恢复退化植被的理论和规划、提高荒漠化防治科技含量、提高水资源利用率和投入支持力度、建立荒漠化土地监测与预警体系等方面进行了分析探讨，为今后进行荒漠化防治提出了对策措施。     

中国荒漠化防治国际合作历程与展望

荒漠化面积占全球陆地面积1/4,影响了全球1/5的人口,直接危及全球粮食和生态安全,导致饥饿和贫困,阻碍发展和经济增长。应对荒漠化挑战是人类共同的责任,需要国际社会共同努力。中国政府高度重视荒漠化防治,中共十八大以来生态文明建设被提升至前所未有的高度。文中通过重点分析中国荒漠化防治国际合作的发展历程、现状、趋势和展望,旨在为出境机构及企事业单位更好地参与当地相关产业的合作与发展,推进防治荒漠化技术“走出去”、“‘一带一路’绿色发展联盟”建设、“一带一路”国际科学组织联盟建设以及加强跨境生态合作提供参考依据。     

中国荒漠化和沙化状况公报

前言 中国是世界上荒漠化和沙化面积大、分布广、危害重的国家之一，严重的土地荒漠化、沙化威胁着我国生态安全和经济社会的可持续发展，威胁中华民族的生存和发展。为掌握全国荒漠化和沙化土地的现状及动态变化趋势，为国家制定防治荒漠化和防沙治沙宏观决策提供科学依据和基础数据，履行《联合国防治荒漠化公约〉的有关义务，国家林业局（原林业部）分别于1994年和1999年组织完成了第一次和第二次全国荒漠化和沙化监测工作，其成果为全国生态建设和防沙治沙工作提供了决策依据，并初步建立了较为完善的全国荒漠化和沙化监测体系。     

内蒙古荒漠化现状与防治对策

内蒙古是全国荒漠化土地最多的省区之一,全区荒漠化土地面积64万km2,风蚀荒漠化土地占91.6%,水蚀荒漠化土地占4.4%,盐渍荒漠化土地占4.0%.荒漠化以及因荒漠化引发的生态问题造成的危害十分严重.荒漠化防治必须树立系统思想,实行综合治理,采取有效措施,保护和合理利用水资源、植物资源,加强科技支撑和技术推广,制定总体规划,分项实施,进行体制创新,提高效益.     

坚持用系统观念积极推进荒漠化综合防治

<正>2023年6月，习近平总书记在内蒙古考察时，主持召开加强荒漠化综合防治和推进“三北”等重点生态工程建设座谈会中强调，加强荒漠化综合防治，深入推进“三北”等重点生态工程建设，事关我国生态安全，事关强国建设，事关中华民族永续发展，是一项功在当代、利在千秋的崇高事业。加强荒漠化综合防治，筑牢我国北方重要生态安全屏障，是内蒙古必须牢记的“国之大者”，必须坚持用系统观念积极推进。     

甘肃省石羊河流域生态安全评价研究

荒漠化地区生态安全评价和防治是国内外学者研究的焦点。以甘肃省石羊河流域为例,构建了生态安全指标体系,进行了生态安全评价,提出了荒漠化防治的措施和建议。结果表明:石羊河流域生态安全居中,北部地区较差,绿洲面积、经济发展和水资源利用是影响流域生态安全的主要因素;自然因素和人为因素是流域生态安全和荒漠化现状的主要驱动力。为甘肃省其他地区的生态安全和荒漠化防治提供理论依据和参考。     

防治荒漠化:让妇女参与

2006年5月29日-6月1日,“妇女与防治荒漠化”国际会议在北京召开,49个国家、5个国际组织和4个外国驻华机构代表150多人参加了会议。会议探讨了妇女在干旱地区所面临的挑战和机遇,强调了在可持续发展和权力框架下的“妇女与环境”问题,奠定了妇女在防治荒漠化中起到的重大作用和贡献。荒漠化影响着全球2/3的国家和地区、1/5人口的生存和发展。气候变化可以加剧荒漠化的过程,但许多荒漠化是人类活动使之加剧。过度的耕种使我们失去了肥沃的土地和水源,过度的放牧使草场变成了土场。“荒漠化”脆弱的生态现象使得人们依靠农业生产获得的收入逐…     

Photosynthetic Characteristics of Ash and Larch in Mixture and Pure stands

IntroductionDuringthepasttwodecades,studieshaverevealedthatgrowingash(Fnainusmandshurica)andlarch(LarlksPP.)togetherinaproperwaycanincreasetheproduc-tivityQfthestandsI"'}'-'].Theyieldimprovementmechanismsattributetotwoaspects,i.e.,theabovegroundandundergr…     

Effects of nutrition spatial heterogeneity on root traits and carbon usage by roots of Cercis chinensis seedlings in split root rooms

In natural ecosystems, nutrition available for plants shows great spatial heterogeneity. Much is known about plant root responses to the spatial heterogeneity of nutrition, but little is known about carbon usage in roots in nutrition-deficient patches and its effect on root longevity. In this study, split-room boxes were used for culture of Cercis chinensis seedlings, and the small rooms were supplied with different nutrition levels. The number of the first-order roots in the rooms with nutrition supply was significantly higher than that in the rooms with deficient nutrition. Specific root length （SRL） of the first-order roots in the rooms with deficient nutrition reached its peak at day 64 after nutrition treatment. There was no significant SRL differences between the two order roots during the experiment. Biomass of the first-order roots in the rooms without nutrition supply was significantly less than that of the first-order roots in the rooms with nutrition supply from day 64 to 96. The total biomass of the lateral roots in the rooms without nutrition supply decreased from day 64 to 96. The activities of the enzymes in roots in the rooms without nutrition supply increased and the activities of alkaline invertases in roots in the two sides of split box did not change significantly. The activities of the enzymes in roots in the rooms without nutrition supply increased gradually. These results suggest that nutrition spatial heterogeneity induced the changes in root traits and plants actively controlled carbon usage in roots in nutrition-deficient patches by regulating the activities of invertases and sucrose synthases, resulting in the reduction in carbon usage in the roots in nutrition-deficient patches.     

Effects of nutrition spatial heterogeneity on root traits and carbon usage by roots of Cercis chinensis seedlings in split root rooms

In natural ecosystems, nutrition available for plants shows great spatial heterogeneity. Much is known about plant root responses to the spatial heterogeneity of nutrition, but little is known about carbon usage in roots in nutrition-deficient patches and its effect on root longevity. In this study, split-room boxes were used for culture of Cercis chinensis seedlings, and the small rooms were supplied with different nutrition levels. The number of the first-order roots in the rooms with nutrition supply was significantly higher than that in the rooms with deficient nutrition. Specific root length (SRL) of the first-order roots in the rooms with deficient nutrition reached its peak at day 64 after nutrition treatment. There was no significant SRL differences between the two order roots during the experiment. Biomass of the first-order roots in the rooms without nutrition supply was significantly less than that of the first-order roots in the rooms with nutrition supply from day 64 to 96. The total biomass of the lateral roots in the rooms without nu-trition supply decreased from day 64 to 96. The activities of the enzymes in roots in the rooms without nutrition supply increased and the activities of alkaline invertases in roots in the two sides of split box did not change significantly. The activities of the enzymes in roots in the rooms without nutrition supply increased gradually. These results suggest that nutrition spatial heterogeneity induced the changes in root traits and plants actively controlled carbon usage in roots in nutrition-deficient patches by regulating the activities of invertases and sucrose synthases, resulting in the reduction in carbon usage in the roots in nutrition-deficient patches.     

Transverse swelling behavior of hinoki (Chamaecyparis obtusa) revealed by the replica method

Transverse swelling and its anisotropy in hinoki (Chamaecyparis obtusa) in several kinds of organic liquids and in water were investigated by means the replica method. There was more cross-sectional swelling of cell walls and cell wall thickness in earlywood than in latewood. Marked swelling toward cell lumens was observed in wood swollen in liquids that had higher swelling potentials than water. This suggests that the swelling of cell walls in these liquids is much greater than the external swelling. Feret's diameters of the cell lumens were reduced by swelling in all the observed cases except in the tangential direction of earlywood, suggesting that cell walls swell to a much less extent in width than in thickness. Deformation of cell shapes caused by the tensile force from the latewood were observed in the earlywood and in the transitional region from earlywood to latewood. When swollen in water, transverse swelling anisotropy caused only by the swelling in cell wall thickness were calculated to be 1.2 for the whole region over an annual ring and 1.4 for the earlywood. These values could not account for the external swelling anisotropy of 2.1. Considering obvious deformations of cell shapes in the earlywood and in the transitional region, we conclude that the interaction between earlywood and latewood is one of the prime factors contributing to the transverse swelling anisotropy of coniferous wood.Part of this report was presented at the 48th Annual Meeting of the Japan Wood Research Society, Nagoya, April 1998     

香榧细小卷蛾生物学特性及防治研究

香榧细小卷蛾Lepteucosma torreyaeWu et Chen是危害香榧的主要害虫之一,在浙江省绍兴市1 a发生2代,以老熟幼虫在枯枝落叶中做茧越冬,翌年2月中旬化蛹,3月上旬成虫羽化并产卵,3月下旬第1代幼虫孵化,5月中旬化蛹,5月下旬成虫羽化,6月上旬产卵,6月中旬第2代幼虫孵化,11月上旬开始越冬。在第2代幼虫期,使用1.8%阿维菌素乳油、5%抑太保乳油、2%阿维苏云制剂、35%吡虫啉乳油及20%杀灭菊酯乳油等5种药剂10个浓度进行喷雾防治试验,施药9 d后,防治效果均达到100%。     

Weather and human impacts on forest fires: 100 years of fire history in two climatic regions of Switzerland

Understanding the factors driving past fire regimes is crucial in the context of global change as a basis for predicting future changes. In this study, we aimed to identify the impact of climate and human activities on fire occurrence in the most fire-prone regions of Switzerland. We considered forest fires, land use and meteorological data over the period 1904-2008 in the neighboring mountain cantons (states) of Valais and Ticino, which are characterized by distinct climatic regimes.The presence/absence of fire ignitions was analyzed using the Nesterov ignition index (as a proxy for fire weather), road density (for ignition sources), livestock density (for biomass removal), and change in forest area (for fire-prone abandoned agricultural areas).We found that fire weather played a key role in fire occurrence in both regions. Road and livestock densities had similar influences in the two cantons. However, while the increase in forest area was well correlated with fire occurrence in Ticino, no such correlation was evident in Valais, probably because land abandonment and forest cover change have been less extensive there. Our findings emphasize the non-linear nature of the relationships between fire occurrence and anthropogenic drivers, as we found thresholds above which road density was no longer correlated with fire occurrence. This implies that the projected future increase and spatial concentration of the human population may not result in a further increase in fire risk in intermediately to densely populated areas in both cantons.The driving factors behind fire activity differ slightly in the two cantons, in particular with increasing forest area enhancing fire occurrence in Ticino but not in Valais. These differences should be taken into account when assessing future fire risk, especially in Valais where the potential for an increase in the fire-prone area is still high. Fires are likely to become more frequent in a warmer climate, but future fire activity may develop differently in the two cantons. This should be taken into account when planning optimized fire prevention measures. This case study should help to better understand fire activity in highly populated regions where fire activity is still moderate but might markedly increase under a projected more fire-prone climate.     

北京八达岭植物群落多样性特征分析

根据34个样地的调查资料,分析了该地区森林植物群落物种多样性的特征:群落内各层物种丰富度指数的大小为草本层>灌木层>乔木层;多样性指数的大小为乔木层<灌木层和草本层。灌木层与草本层的多样性指数随林分郁闭度变化而变化,在林分郁闭度为25%的侧柏黄栌混交林中,灌木层的多样性指数和丰富度指数小于草本层;在郁闭度53%的杂木林中,灌木层和草本层的多样性指数接近;在郁闭度53%以上的各个群落内,草本层的多样性指数和丰富度指数基本上都大于灌木层。人工林中的物种多样性变化多样,明显低于天然林,林分层次单一,更新不良,缺乏灌木层和地被植物,生态系统很不稳定。     

杉木人工林间伐后林下植被养分动态的研究──Ⅰ.林下植被营养元素含量特点与积累动态

杉木林林下植被的生长与发育,对林地地力的恢复具有重要意义．通过对定位试验地杉木人工林林下植被营养元素的分析,研究了杉木林间伐后林下植被营养元素含量与积累状况．结果表明;营养元素在植物不同器官中的含量是不同的;问伐区灌木层和草本层植物中大量元素和微量元素的积累量大于对照区,草本植物中营养元素积累的增长幅度不如灌木层植物大;间伐后林下死地被物中大多数营养元素含量和积累量均有所增加．     

皆伐方式对小兴安岭低质林土壤呼吸的影响

针对小兴安岭低质林分,采用不同的皆伐方式,利用LI-8100碳通量自动监测系统在春、夏、秋、冬4个季节对低质林分土壤呼吸进行观测,运用统计分析的方法,分析皆伐方式对土壤呼吸的影响和不同皆伐方式的土壤呼吸产生差异的原因.结果显示:试验区土壤呼吸夏季最大,冬季最低.春季和秋季因土壤温度和湿度差异不大使土壤呼吸相差较小;对于水平带同一条皆伐带,土壤呼吸并无显著性差异,并且不同的带宽对土壤呼吸的影响也不显著;垂直带随海拔升高土壤呼吸呈现波动性,总体趋势随海拔升高土壤呼吸逐渐降低,但是差距较小;水平带、垂直带和林窗的年土壤呼吸量分别为1.184,1.426,1.179 kgCO2·m-a-1,垂直带最高,水平带次之,林窗最低.影响垂直带土壤呼吸的关键因素是土壤温度,林窗则是土壤湿度,而水平带土壤温度和湿度的条件则介于垂直带和林窗之间.这说明在不同的皆伐方式条件下,影响土壤呼吸的关键因素并不完全相同.     

新世纪木工机械新理论研究的成果综述

综述了国内外木材加工机械行业的理论发展现状,找出了国内木材加工行业与国际先进水平的差距,提出了木材加工行业未来的发展趋势,总结了木工机械机电一体化技术的新成果和木工机械检测技术的新进展。着重介绍了新西兰林科院在木材视频技术和木材缺陷探测方面的一些研究成果,综述了人造板加工机械和木材加工机械的新理论研究。