北京市林业用地价值核算

<正> 一、北京市林业用地概况 根据北京市“八五”森林资源二类调查,北京市林业用地概况为: 1.林业用地面积:北京市总面积166.6667万公顷,林业用地面积82.9149万公顷,占全市总面积49.7％;非林业用地面积83.7518万公顷,占全市总面积50.3％。在林业用地中,有林地面积46.4594万公顷,占林业用地面积56.0％。疏林地面积1.6798万公顷,占2.0％;灌木林地面积17.3797万公顷,占21.0％;未成林造林地面积2.8303万公顷,占3.4％;苗圃地面积0.3363万公     

基于遥感和GIS的黄土高原中阳县土壤侵蚀评价

黄土高原地区是我国水土流失最严重的地区,定量评价土壤侵蚀量、土壤侵蚀强度及其空间分布特征,可以为水土流失防治措施的制定提供依据.基于遥感和GIS,应用修正的通用土壤流失方程(RUSLE)对山西中阳县土壤侵蚀进行评价.结果表明,中阳县平均土壤侵蚀模数为2 874.25t/(km2·a),属于中度侵蚀地区,年平均土壤侵蚀量408.78×104 t.发生中度以上土壤侵蚀面积占总面积的29.95％,土壤侵蚀量占总侵蚀量的85.61％,这部分土地是土壤侵蚀防治的主要区域.黄土区发生轻度以上土壤侵蚀面积大,所占比例多,侵蚀程度严重.微度土壤侵蚀面积以有林地为主,轻度和中度土壤侵蚀面积主要是未成林造林地和灌木林地,发生强烈以上土壤侵蚀面积主要是疏林地、未利用地、灌木林地和农田,土地类型、植被覆盖与土壤侵蚀有着密切关系,林业生态工程建设对于中阳县控制水土流失和改善生态环境有着重要作用.     

深化改革 依靠科技振兴山区林业——山西省绛县林业发展的点滴调查

<正> 山西省绛县地处中条山西北麓,是个多山少川的地方,坡、沟地貌构成了当地的主要特色,是山西省40个林业重点县之一。全县土地面积149万亩,其中林业用地72万亩,占48.32％。有林地52万亩,占林业用地的72.22％。宜林地20万亩,占林业用地面积的27.78％。近年来,在县委、县政府的正确领导下,林业部门的广大干部、职工,坚持改革开放的方针,本     

晋陕蒙接壤区林草覆盖变化的遥感分析

以晋陕蒙接壤区1986年和2000年的TM影象为信息源,运用遥感技术与地理信息系统技术,结合建立了两期全区土地资源数据库,从中提取林草覆盖空间数据.分析得出2000年全区有林草地面积332.19×104hm2,占总面积的56.87%,其中林地占13.72%,草地占86.28%.14年间林草植被净增加了2.29×104hm2,占林草面积的0.69%,总的变化趋势是林草覆盖对生态环境的保护和调节功能趋向衰减.林地被毁、草地开垦和沙漠化是林草覆盖减少的主要原因,而其新增部分主要是实施植树造林、退耕还林还草等生态环境建设措施的结果.     

雅安国有人工商品用材林经营现状与对策

<正> 四川雅安市国土面积1.52万平方公里,山地占94％,森林覆盖率45％。林业用地110万公顷。全市有国有森工企业局1个,国有林场(所)15个,国有林地总面积72万公顷,森林总面积43万公顷,总蓄积6300万立方米。其中公益林面积为39万公顷,占92.4％,绝大部分为天然林或天然次生林;商品林面积3万多公顷,约占8％,全部为人工林。     

我国人工林生产力长期保持问题

<正> 人工林的发展在世界范围内都很受重视。世界人工林现在有1.35亿公顷,其中温带占75％,热带、亚热带占25％。热带人工林面积1965年占世界人工林的8％,1979年约占13％,1990年约占25％。中国近年每年人工林保存面积为330万公顷,速生丰产林15年间要营造667万公顷,相当于年平均营造40～50万公顷。从总体看世界人工林面积虽然只占世界天然林面积的3％,但人工林的     

阿坝藏族羌族自治州土地资源特征

四川省阿坝藏族羌族自治州(简称自治州)地处青藏高原东南缘,南北长414公里,东西宽约360公里,平均海拔3000米以上,属川西北高寒地区,是四川省林牧业重要基地。全州总土地面积为834.26万公顷(12513.93万亩)。其中,草地面积为421.90万公顷,占土地总面积的50.6％;林地304.94万公顷,占36.3％;耕地仅9.93万公顷,占1.2％;水域5.94万公顶,占0.7％。草地、林地、耕地和水域用地比值为71.0:51.0     

贵州省长顺县摆茶大队山地利用

摆茶大队位于长顺县南部,土地面积5.35平方公里,海拔1100—1440米,气候温暖湿润,年均温15℃,≥10℃积温值4650℃,无霜期280天,年雨量1365毫米。该大队属亚热带山地,其自然条件和农业生产状况在我国南方有比较广泛的代表性。 在大队土地总面积中,有耕地1145亩,约占14％;林地1600亩,约占20％,其中用材林1307亩,占林地面积的82％;其他主要为荒山和草坡所占据。大队境内可以大致分为四个地貌类型,即河谷平坝、灰岩丘陵、砂页岩丘陵台地和砂页岩中山。它们的土地利用方式有着明显的差别(附表)。     

南江县发展立体农业的体会和构想

南江县是个山区县,位于106°27′—107°10′E,31°50′—32°45′N,在川北边缘,大巴山南坡。人口52万。全县土地面积3446.7平方公里(517.0万亩),其中宜林地面积2340.0平方公里(351.0万亩),占全县土地面积的67.9％,大部分分布在海拔800     

河北农业用地规划问题浅论

土地是农业赖以进行的不可替代的生产资料,又是国民经济各部门和人民生活须臾不可离开的基础。农业用地是土地利用的主要组成部分。河北省土地总面积18.7万平方公里,目前农业用地,(包括农、林、牧三业用地和水产养殖及农田水利占地)占74.8％,其中,耕地占40.8％,林地占16.3％,牧草地占16.7％,工交城乡等建设用地占10.6％,尚有14％左右的土地资源未被利用,已利用的也多不尽合理。因此,研究农业用地问题,作好农业用地规划,不仅关系到整个国土资源的开发和利用,而且关系到农业经济的调整,关系到     

我国森林资源的保护和合理开发利用

40年来,特别是近10年来,我国森林面积有所增加。这对保护生态环境、支援经济建设、改善群众生活起着重要的作用。但发展很不平衡,有些林区森林质量下降严重,问题不少。为改变这种局面,要采取十项措施。     

广西土地合理利用与生态环境建设探讨

生态环境的破坏与建设与土地利用是密切相关的，分析了广西土地类型和土地利用现状，探讨了由于土地不合理利用导致的生态环境问题，提出了通过合理利用土地来建设生态环境的措施。     

我国的土地资源

本文通过与世界土地资源的对比,详细论述了我国土地资源的数量、质量、利用问题及利用途径。随着人口数量的增长,我国土地资源与粮食需求之间的矛盾日益尖锐。目前我国地力减退,土地承载力下降,水土流失,土地沙化,土壤盐碱化及沼泽潜育化,耕地侵占等问题较为严重。为合理开发利用我国的土地资源,本文提出了一些合理化建议,并将全国分成8个土地利用区,进行扼要说明。     

森林利用的冲突与调解途径理论探讨

森林价值的多样性和利用群体的多样性,是森林利用冲突的根源,也决定了森林利用的冲突形式。同一社会中,不同利益群体从各自的利益和兴趣出发,竞相利用有限的森林资源的各种价值,导致森林利用的冲突,冲突若不及时解决,将影响森林为人类社会持续提供价值。是伴随着森林管理的一种不可避免的现实,不论是哪一种管理方式都存在着这样或那样的冲突。解决的途径也不相同,包括技术途径、调解、仲裁和诉诸法律等。村社林业是相对于政府直接控制管理森林的另一类林业管理方式,村社林业的实践也需要解决冲突,建立和培养村社解决冲突的机制和能力是开展村社林业的一项重要任务。村社林业管理模式的成功需要建立冲突的调解和仲裁机制,透明、参与、合作和创造是建立这种机制并使这种机制发挥作用的基础。     

海南岛森林资源的特点及林业可持续发展对策

分析了海南岛森林资源的特点,指出林业生产存在的主要问题。根据其特点,构建森林资源可持续经营管理的基本模式,并对海南林业可持续发展提出相应的对策。     

新疆森林资源动态分析

1 M ethod ofsurvey and analysis1.1 Survey area and dataThe survey area am ounted to 1.647 m illion km 2,covering the w hole territory of X injiang.TheLandsat TM im age data obtained from rem ote sensing in w hole X injiang during the periods1995-1996 and …     

Simulation on the dynamics of forest area changes in Northeast China

There is plenty of forests in Northeast China which contributes a lot to the conservation of water and land resources, produces timber products, and provides habitats for a huge number of wild animals and plants. With changes of socio-economic factors as well as the geophysical conditions, there are dramatic changes on the spatial patterns of forest area. In this sense, it is of great significance to shed light on the dynamics of forest area changes to find the underlining reasons for shaping the changing patterns of forest area in Northeast China. To explore the dynamics of forest area change in Northeast China, an econometric model is developed which is composed of three equations identifying forestry production, conversion from open forest to closed forest and conversion from other land uses to closed forest so as to explore the impacts on the forest area changes from demographic, social, economic, location and geophysical factors. On this basis, we employ the Dynamics of Land System (DLS) model to simulate land-use conversions between forest area and non-forest cover and the land-use conversions within the sub-classes of forest area for the period 2000–2020 under business as usual scenario, environmental protection scenario and economic growth scenario. The simulation results show that forest area will expand continuously and there exist various kinds of changing patterns for the sub-classes of forest area, for example, closed forest will expand continuously and open forest and shrub will decrease a little bit, while area of other forest will keep intact. The research results provide meaningful decision-making information for conserving and exploiting the forest resources and making out the planning for forestry production in the Northeast China region.     

Dynamic analysis and evaluation of Xinjiang forest resources: based on RS and GIS

The forest resources in Xinjiang were surveyed and analyzed based on RS and GIS. Satellite data interpretation was adopted to obtain the general situation of Xinjiang forest resources in assistance with the sampling method and on-the-spot investigations. Based on GIS, related data obtained from satellite remote sensing in 1996 and 2001 were studied through contrastive analysis. Moreover, the dynamic variation of Xinjiang forest resources was studied in an all-around way. In the past five years, the areas of the forestland, woodland, sparse woodland, nursery garden and the land usable for forestry in Xinjiang kept growing, moreover, the forest cover rate and the total standing stock volume increased correspondingly, showing that the wooded area and the amount of growing stock in Xinjiang were increasing. The forestland area in Xinjiang went up to 17,837 km2 from 17,331 km2, with an annual average increase of 101 km2. Accordingly, the forest vegetation came to 1.08% from 1.05%, up 0.03 percentage point; the total standing stock volume went up to 289,985,200 m3 from 262,416,000 m3, a total increase of 27,569,200 m3, an annual average increase of 5,514,000 m3 and an annual average net growth rate of 2.00%. The analysis results showed that the forest resources in Xinjiang were increasing on the whole, however, there remained some problems, such as the sparse natural forests, low forest cover rate, imbalanced wood age structure, and mono tree species composition, etc.     

建水县林地保护利用研究

利用实地调查法、GIS和相关分析法研究分析建水县林地保护利用现状及存在的问题,研究发现：建水县建设占用与林地保护矛盾突出;林地生产力较低;林地树种结构较单一,生态功能比较脆弱;大多数林地分布在地质灾害中高易发区,地质灾害对林地破坏较大;林地保护管理队伍难以满足现实需求.研究结论：根据林地保护级别对林地实施分级管护,要依法正确处理林地保护和建设占用的关系,完善林地保护管理队伍,建立健全管理机构,加强林地的防灾、抗灾、减灾能力建设,大力促进天然林、人工林和经济林的合理有效培养和发展.     

中国东北地区林地面积变化的动态模拟

There is plenty of forests in Northeast China which contributes a lot to the conservation of water and land resources, produces timber products, and provides habitats for a huge number of wild animals and plants. With changes of socio-economic factors as well as the geophysical conditions, there are dramatic changes on the spatial patterns of forest area. In this sense, it is of great significance to shed light on the dynamics of forest area changes to find the underlining reasons for shaping the changing patterns of forest area in Northeast China. To explore the dynamics of forest area change in Northeast China, an econometric model is developed which is composed of three equations identifying forestry production, conversion from open forest to closed forest and conversion from other land uses to closed forest so as to explore the impacts on the forest area changes from demographic, social, economic, location and geophysical factors. On this basis, we employ the Dynamics of Land System (DLS) model to simulate land-use conversions between forest area and non-forest cover and the land-use conversions within the sub-classes of forest area for the period 2000–2020 under business as usual scenario, environmental protection scenario and economic growth scenario. The simulation results show that forest area will expand continuously and there exist various kinds of changing patterns for the sub-classes of forest area, for example, closed forest will expand continuously and open forest and shrub will decrease a little bit, while area of other forest will keep intact. The research results provide meaningful decision-making information for conserving and exploiting the forest resources and making out the planning for forestry production in the Northeast China region.