浙江省森林生态系统五大碳库碳汇功能及结构特征

为准确评估浙江省森林生态系统5个碳库碳储量,基于浙江省森林资源年度监测体系,建立了各碳库基础数据外业调查、样品采集系统抽样调查体系,并在全省共调查地上、地下和枯死木碳库样地4252个,调查枯落物、土壤碳库样地906个.以样地为基本单元,运用系统抽样估计方法,测算了各碳库碳储量,分析了各碳库碳储量结特征,提供了评估结果的...     

中国南方复杂地形森林样地的测量标定方法

【目的】中国南方存在很多地形复杂的喀斯特和非喀斯特区域,在这些地形陡峭的区域进行森林监测样地测量标定时,一般容易出现测量误差较大和一般测量方法适用性不佳的问题。为此,本研究提出一种适用于复杂地形的森林样地测量标定方法。【方法】以全站仪放样测量为基础,充分利用复杂地形中一般岩石出露较多的特点,改进定桩点标记方法,同时改进制点的选择方法并编制相应的计算器程序。【结果】利用该方法,成功地在地形复杂的弄岗国家级自然保护区的喀斯特森林标定了1个15hm~2的样地,并在地形同样复杂的十万大山地区标定了多个1hm~2的森林样地。【结论】本方法适用于地形陡峭复杂的喀斯特地区和非喀斯特地区,在测量大型森林监测样地时,具有较高的精度。     

基于GF-2的乔木生物量估测模型研究

以福建省将乐林场为研究区,使用野外实测样地数据,结合福建省二类调查数据,获取了共192个样地的生物量数据,其中杉木纯林112个,马尾松纯林80个．对覆盖研究区的2景GF-2影像进行预处理,提取光谱信息、植被指数、纹理特征及地形因子,筛选与样地生物量相关性较高的因子作为建模的自变量,采用支持向量机、随机森林及多元逐步回归3种方法分别建立了杉木和马尾松生物量模型．结果表明:支持向量机、随机森林模型拟合效果均比多元逐步回归模型好,其中随机森林模型决定系数R2最高,2种样地的R2分别为0.65和0.72,估计精度也最高,分别为65.28%和76.82%;杉木样地3种模型的均方根误差分别为64.27、48.16和77.03,马尾松样地3种模型的均方根误差分别为54.79、48.18和65.63,其中随机森林模型的最低．在3种模型中,随机森林模型为乔木生物量的最优模型．      

松辽平原玉米遥感估产采样框架的布设研究

利用遥感技术对玉米进行大面积、快速地长势动态监测，随作物主要生长期的变化进行动态估产，必然依赖于地面样地所提供的各种参数。如何在广大区域布设具有可靠和代表性的采样框架，是遥感估产的一个关键问题。为满足面积估算和单产预测要求，必须采取布设多级样地的采样格局。多级样地的布设应该建立在综合估产区划的基础上，根据综合估产区划体系布设与之相适应的各类样地。在各类样地上，分别进行农学参数、环境背景参数的观测和     

华北落叶松天然次生林树高曲线的混合效应模型

【目的】建立华北落叶松天然次生林树高曲线,为森林可持续经营提供技术支撑。【方法】基于116块华北落叶松天然次生林样地单木数据,从11个具有生物学意义的备选模型中选出一个最优基础模型。考虑地域和样地对树高曲线的干扰,基于94块样地利用带哑变量的非线性混合效应模型构建了树高曲线,并对22块样地数据进行验证。【结果】利用全部数据拟合11个备选模型,其中最优模型是Logistic方程,决定系数为0.765 3,均方根误差为3.279 4。引入哑变量和随机效应后,所建模型决定系数为0.915 2,均方根误差为1.892 2,与基础模型相比拟合精度显著提高。验证数据结果表明,带哑变量的非线性混合模型对树高的预测效果良好。【结论】样地随机效应对华北落叶松树高曲线干扰较大,当模型考虑这些随机效应对树高曲线的影响时能显著提高模型预测精度。该模型可用于华北落叶松天然次生林其他样地树高的预测。     

基于蜥蜴干扰的大针茅草原补偿生长研究

基于内蒙古锡林郭勒盟大针茅草原毛登牧场的生态监测,进行实地采样,通过对围封样地、大针茅样地、蜥蜴样地进行对比,研究蜥蜴活动对大针茅草原地上生物量、物种多样性、植物个体形态的干扰作用,进而探讨蜥蜴干扰对不同植物类群补偿效应的影响.结果表明,蜥蜴活动对大针茅草原地上总生物量增加的影响极显著(P<0.01),对大针茅草原生物多样性增加的影响显著(P<0.05).大针茅和羊草个体生物量在样地间存在差异,羊草生物量由大到小排序为围封样地、蜥蜴样地、大针茅样地;大针茅生物量由大到小排序为大针茅样地、蜥蜴样地、围封样地.通过样线法对蜥蜴活动的生境状况进行调查,表明蜥蜴活动所在生境的斑块的周长与聚集的洞穴的个数成线性关系.     

常绿落叶阔叶混交林群落定量分析方法比较

利用无样地抽样法和样方法对万罗山自然保护区常绿落叶阔叶混交林群落进行调查 ,并对其调查数据进行关联度分析 ,得出无样地抽样法与经典样方法的关联度均大于 0 .7,证明无样地抽样法在常绿落叶阔叶混交林群落调查中的应用是可靠的 ,为我国山地常绿落叶阔叶混交林调查使用不同方法提供了依据。     

无样地法在我国温带山地森林中的应用

在植被研究中,野外取样是一项十分重要的工作。它不仅关系到野外工作效率问题,而且影响所取得的数据是否有代表性的问题。目前,世界上有关植被野外取样方法有两大类:样地法(plot method)和无样地法(plotless method)。根据国内外研究表明见参考文献([1]、[2]、[3]、[4]、[5]),无样地法比样地法有代表性强、操作简便和工作量少     

基于森林连清数据的林分直径结构生长规律研究

根据连续清查的固定样地及样木检尺有关数据,选择人工起源的同龄纯杉木样地２２６块,采用三参数Ｗｅｉｂｕｌｌ分布对每块样地的直径分布进行拟合,通过对分布参数与林分年龄的变化关系分析,提出大地域上林分直径结构生长的普遍规律。     

弄岗淡黄金花茶种群年龄结构与空间分布格局

淡黄金花茶Camelia flavida Chang是一种具有黄色花瓣山茶属植物,具有一定的观赏价值。本文以广西弄岗自然保护区2个固定监测样地NG(300m×500m)和CS(100m×100m)内的淡黄金花茶种群为研究对象,分析其种群年龄结构,并利用单变量和双变量g(r)函数分别分析其种群分布格局和3个不同生活阶段之间的空间关联性。结果表明:(1)NG样地淡黄金花茶年龄结构近似呈正态分布,为稳定型;CS样地年龄结构近似倒"J"型,为增长型;(2)淡黄金花茶在NG和CS样地存在显著聚集分布格局的距离分别为24m和35m,前者的聚集程度明显大于后者;(3)相同样地内淡黄金花茶3个不同生活阶段之间的空间关联性相似,在24m范围内均表现显著正相关。     

黑河下游荒漠河岸林植物水分传输观测试验研究

荒漠河岸林是长期适应干旱区内陆河流域环境的产物,具有独特的水分利用和生存策略.对黑河下游胡杨、柽柳等主要荒漠河岸林植物液流、水势、木质部导水率、根系水分再分配以及植物水分来源等的测试分析表明,在降水稀少、蒸发强烈的黑河下游,胡杨、柽柳主要利用的是深层土壤水和地下水,其中成熟胡杨主要吸收地下175~325cm处土壤水和地下水供其蒸腾和生存所需;胡杨根系水力提升过程主要发生在10~70cm土层,蒸散导致的土壤耗水量中有10%来自根系提升的水量;植物根和枝条木质部的初始导水率(K_(s0))和最大导水率(K_(s,max))相对较高,其中柽柳木质部的潜在导水能力比胡杨强;胡杨、柽柳液流速度呈单峰型,在午后达到峰值,黎明前水势无显著变化,反映未受到严重水分胁迫;黑河下游河道附近的地下水埋深大多在4m以内,基本可以满足荒漠河岸林植物的生长发育,黑河下游荒漠河岸林生态系统处于稳定和发展状态.     

Response of the accumulation of proline in the bodies of<Emphasis Type="Italic">Populus euphratica</Emphasis> to the change of groundwater level at the lower reaches of Tarim River

The content of proline in the plant bodies is closely related to the converse-succession-resistant capability of plants. Under the drought stress, the proline accumulates rapidly in the plant bodies for maintaining a certain mois-ture content and an expanding-pressure momentum in cells through the osmoregulation, thus the drought-resis- tant capability and the converse-succession-resistant ca-pability of plants are increased[1,2]. Many researches on the relationship between the proline and the…     

干旱区内陆河流域荒漠河岸林变化研究

新疆塔里木河流域以胡杨为建群种的荒漠河岸林是我国及世界上胡杨分布最为集中的地区之一。通过分析该地区土壤含水率、地下水埋深、地形地貌类型与胡杨空间分布、龄级结构、郁闭度的关系,探讨其生长状况。同时,采用１９８３年、１９９２年及１９９６年遥感信息源编制植被专题图件,在ＧＩＳ支持下处理图件,并应用制图数据及相关自然及人文数据,分析胡杨面积变化及演替规律,强调了系统重建设及恢复的重要作用。     

额济纳旗胡杨幼叶糖类物质变化

以额济纳国家级胡杨林自然保护区中两种不同样地中的胡杨幼叶为材料,进行可溶性糖和淀粉含量的变化研究,并对胡杨叶的形态结构的生长发育状况进行观测。实验结果表明:胡杨叶形态结构表现为随时间变化,叶的长、宽逐日增大,胡杨叶中可溶性糖的含量随时间变化而明显增大;淀粉含量则随时间变化呈略微增大趋势.在土壤含水量较低的样地,胡杨叶中可溶性糖含量较大,这是对干旱胁迫的一种适应.     

Analysis on water potential of Populus euphratica oliv and its meaning in the lower reaches of Tarim River,Xinjiang

Combined with materials measured on leaves water potential of Populus euphratica oliv in the process of ecological water delivery in the lower reaches of Tarim River, the influence of ground-water depths and soil salinity on leaves water potential of P. euphratica was analyzed. We found that there was evident negative correlation between the leaves water potential of P. euphratica and ground-water depths. The deeper the ground-water depths were, the lower the leaves water potential of P. euphratica was, the more serious drought stress P. euphratica suffered from. Besides, there was evident negative correlation between the soil salinity and the leaves water potential of P. euphratica. The bigger the soil salinity was, the lower the leaves water potential of P euphratica was, the more serious drought stress was indicated from which P. euphratica suffered. For sections rather distant for Daxihaizi Reservoir as well as for those places of wells rather distant from the river course, ground-water depths and the soil salinity were high; the leaves water potential of P. euphratica was low. The leaves water potential of P. euphratica can reflect the degree at which P. euphratica suffers from drought and salt stress, and has an important reference meaning in analyzing proper ground-water depths for the survival and growth of P. euphratic in the lower reaches of Tarim River.     

Analysis on water potential of Populus euphratica oliv and its meaning in the lower reaches of Tarim River, Xinjiang

Combined with materials measured on leaves water potential of Populus euphratica ofiv in the process of ecological water delivery in the lower reaches of Tarim River, the influence of ground-water depths and soil salinity on leaves water potential of P. euphratica was analyzed. We found that there was evident negative correlation between the leaves water potential of P. euphratica and ground-water depths. The deeper the ground-water depths were, the lower the leaves water potential of P. euphratica was, the more serious drought stress P. euphratica suffered from. Besides, there was evident negative correlation between the soil salinity and the leaves water potential of P. euphratica. The bigger the soil salinity was, the lower the leaves water potential of P. euphratica was, the more serious drought stress was indicated from which P. euphratica suffered. For sections rather distant for Daxihaizi Reservoir as well as for those places of wells rather distant from the river course, ground-water depths and the soil salinity were high; the leaves water potential of P. euphratica was low. The leaves water potential of P. euphratica can reflect the degree at which P. euphratica suffers from drought and salt stress, and has an important reference meaning in analyzing proper ground-water depths for the survival and growth of P. euphratic in the lower reaches of Tarim River.     

Analysis on water potential of Populus euphratica oliv and its meaning in the lower reaches of Tarim River,Xinjiang

Science Bulletin - Combined with materials measured on leaves water potential of Populus euphratica oliv in the process of ecological water delivery in the lower reaches of Tarim River, the...     

艾比湖流域阿其克苏河床森林覆盖率调查研究

文章通过对研究区阿其克苏河床森林覆盖率遥感图像分析、胡杨立木胸经与树高在不同监测样地中的对应关系分析以及胡杨树冠覆盖率状况分析等，得出该地区胡杨林整体衰败，已经丧失了自然更新能力，面临着毁灭的危险。因此，加大对研究区生态恢复与重建是今后首要的任务。     

额济纳胡杨有性繁殖失败因素分析

对内蒙古额济纳绿洲胡杨种群的苗库状况、种子雨、种子生活力以及环境因子对种子萌发的影响进行了研究,结果表明:胡杨萌生苗占更新苗的绝大多数;胡杨能够产生出大量的有生活力的种子,胡杨种子散播时间在种群内部存在异质性;在恶劣的自然条件下,胡杨种子在落种后生活力迅速降低,(6-40)d后绝大部分种子(95%)会丧失活力。种子萌发试验表明:表土层含水量低、含盐量高、生化他感作用是胡杨种子萌发的限制性因子。由于胡杨种子属于短命种子,在其短暂的活力期内没有适宜的环境条件使之萌发,从而造成种子萌发失败。缺水所导致的种子安全萌发生境的缺失是额济纳胡杨的有性繁殖失败的首要原因。     

Physiological response of natural plants to the change of groundwater level in the lower reaches of Tarim River, Xinjiang

Based on the analysis of the three-year (2000-2002) monitoring data of the four times intermittent stream water conveyance to the lower reaches of Tarim River where the stream flow was dried up for more than 30 years and the measurement of PRO, SOD and POD in plants collected from 24 vegetation plots, it is concluded that the stream water conveyance plays an important role in lifting groundwater level. The groundwater nearby the watercourse was raised from 5～8 m in depth before the stream water conveyance to 2.5～5 m after stream water conveyance. The physiological response of Phragmites communis, Tamarix spp. And Populus euphratica to the change of groundwater is sensitive and represents a grads change obviously. The growth of the plants in the lower reaches of Tarim River is stressed by drought to various degrees. Lengthways, the drought stress exposed to the plants increases with groundwater depth from the upper sections to the lower sections; and breadthwise, the drought stress exposed to the plants is increased with the increase of distance away from the river channel of stream intermittent water releases and of the groundwater depth. Combining the field investigation and the analysis of the plots, it is considered that the stress groundwater depths for the Phragmites communis, Tamarix spp. And Populus euphratica are 3.5 m, 5 m and 4.5 m respectively.