旅游活动对张家界世界地质公园土壤影响的研究

在调查张家界世界地质公园土壤影响形态及影响范围的基础上,对公园游道两边不同距离土壤的硬度、含水率、容重进行了测定和分析,并通过计算各游览区土壤影响指数(SII)来评价旅游活动对公园土壤的综合影响。结果表明:游客活动对张家界世界地质公园土壤产生了较大的影响,特别是在游客相对集中的黄石寨景区和金鞭溪景区,影响十分明显;游客对土壤影响的范围主要发生在距游道两侧3米以内的范围;公园内土壤影响形态可分为单侧节型、双侧节型、单侧链型、双侧链型、十字节型和捷径链型6种类型,其中又以单侧节型和双侧节型为主;在六个景区中,距游道边缘1米、2米及3米范围内土壤的平均含水率较对照区分别低了36.6%、24.5%和2.2%;与对照区相比,距游道边缘1米、2米及3米的土壤硬度分别增加了167.9%、122.2%和15.8%,而距游道边缘1米和2米范围内的土壤容重则分别比对照区增加了26.5%和20.9%。文章对如何降低游客对土壤的影响范围及程度进行了讨论。图4表3参16。     

旅游活动对张家界国家森林公园植被的影响的评价

在张家界国家森林公园的三个景区(金鞭溪、将军岩、天书宝匣),分别选择了四个区域作为样地,本文通过对树木的刻伤数量,植被的种类,数量等的调查,分析了旅游活动对林木及植被的影响。结果表明,公园游道两边的林木受到了游客的严重刻伤,尤以黄石寨景区及金鞭溪景区最为明显。林木受伤程度主要与树种、树皮光滑程度及林木和游道边缘之间的距离有关。本研究以植被影响指数(IVI)来衡量旅游活动对植被的影响。结果显示,在受影响最大的三个景区,IVI 值位于59.4%与87.5%之间,表明其游道两边的植被已受到了严重的影响。针对以上问题,本文提出了关于公园游客管理的一些建议。表5参10。     

香山公园绿地人为践踏的调查和分析

香山景色秀丽，名胜遍布，风光旖旎，是我国著名的旅游胜地，是中外闻名的北京十大公园之一。香山久负盛名，吸引了来自世界各地的游客，但是旅游途程中，游客有意无意的践踏对绿地造成了恶劣的破坏。从本文调查的数据可知。践踏影响到了绿地中草本植物物种和个体的数量，而且根据计算所得土壤物理量而知，土壤的容重增大，孔隙度减少对植物的生长，水分和矿物质元素的吸收，呼吸作用等生命活动都有较大的抑制，使绿地中的革本植物生长不好，易造成香山公园内小面积的水土流失。本文在分析说明后。对此提出了定期松动土壤，制造隔栏等合理化建议。     

生态旅游对甘肃祁连山国家级自然保护区景区土壤的影响

选取甘肃祁连山国家级自然保护区天祝三峡森林公园、焉支山森林公园、大野口森林公园和马牙雪山生态旅游景区、窟窿峡生态旅游景区、康乐草原生态旅游景区等6个样地,对该自然保护区土壤的物理性状和化学性状进行了监测分析。结果表明,在游客数量多、干扰强烈的区域,游客对土壤践踏严重,土壤孔隙度减低,容重增加,含水量和有机质含量减少,pH值增大,氮、磷、钾含量减少,肥力下降。     

旅游活动对云蒙山国家森林公园土壤影响的初步研究

该文以云蒙山国家森林公园为研究对象 ,采用抽样调查的方法 ,对森林公园的土壤理化性质进行了监测 ,重点分析了旅游活动对森林公园土壤质地、土壤容重、土壤有机质含量、pH值等性质的影响 ,并运用数学模型对影响程度作出定性分析和定量评价。评价结果表明 ,旅游活动已对云蒙山国家森林公园的土壤造成了一定的负面冲击 ,必须采取有效措施减少旅游活动对公园土壤负面冲击 ,维护公园良好的生态环境 ,以实现公园森林旅游业的可持续发展     

东莞林科园人工果林土壤物理性质研究

文章分3个不同坡位和3个土层深度对东莞林科园园内人工果林土壤容重、孔隙度、通气度、水分含量等物理性质进行了研究。结果表明:园内人工果林上层土壤容重最小,土壤孔隙在不同的土壤层次之间和同一土壤层次不同坡位之间的大小变化规律不一致,土壤通气度随着土壤层次的加深逐渐降低,土壤水分在不同土壤层次之间和同一层次不同坡位之间的差异均不大。总体而言,土壤容重、土壤孔隙及土壤水分的差异主要体现在上土层;不同的坡位对人工果林的土壤物理性质影响较显著。     

宜宾市典型城市绿地土壤理化性质分析

采用室内分析和野外调查相结合的方法,研究了宜宾市土壤容重和速效养分现状。结果表明,公园绿地、街头绿地、附属绿地土壤容重能满足植物生长需求,道路绿地土壤容重偏大,影响植物生长;速效氮和速效钾含量能满足植物需求而速效磷含量不足,需要补充。     

旅游干扰对南湾国家森林公园土壤和空气质量的影响

通过对南湾国家森林公园典型景点的土壤和大气指标进行测定,探讨旅游活动对公园土壤的干扰效应及对空气质量的影响。结果表明,不同强度的旅游活动对土壤、大气质量有不同程度的影响,随着旅游活动干扰增强,公园土壤坚实度增加,植物根系深度较浅,土壤容重增加,土壤含水量下降;南湾大坝、新码头的PM2.5含量较高,空气负离子含量较低,空气受干扰影响较大,鸟岛、罗家沟等景点PM2.5含量较低,空气负离子含量较高,空气质量良好。南湾森林公园的发展应充分考虑生态环境的变化,积极应对旅游活动干扰造成的负面影响,以实现公园的生态恢复和重建。     

朔州市林业土壤速效养分及土壤容重分析

系统采集0~20 cm土壤样本,分析朔州市市区林业土壤土壤容重和速效养分现状。结果表明,朔州市公园绿地、街头绿地和附属绿地土壤容重适宜,基本不会影响绿化植物的生长,但道路绿地土壤容重偏大,不利于绿化植物的生长;土壤速效氮含量总体上处于较低水平,大部分林业土壤速效磷和速效钾丰富。       

森林公园游道模型初步研究

游道作为森林公园的重要组成部分，具有游客输送、景观分割、构建资源及旅游赏景的作用。合理的游道系统应在满足旅游功能的前提下，尽量保持森林生态景观的完整性，降低游道系统所造成的景观破碎。通过对森林公园景点的空间结构、旅游功能及景观保护的分析，结合森林公园的实际情况，在森林公园中合理规划游道以使森林旅游得以可持续发展。     

Effects of the vegetation restoration years on soil microbial community composition and biomass in degraded lands in Changting County,China

We evaluated the effects of the number of years of restoration of vegetation on soil microbial community structure and biomass in degraded ecosystems.We investigated the microbial community structure by analyzing their phospholipid fatty acids then examined microbial biomass carbon and nitrogen by chloroform fumigation extraction of restoration soils over several years.The data were compared with those of highly degraded lands and native vegetation sites.The results show that the duration of vegetation on the sites substantially increased microbial biomass and shifted the microbial community structure even after only 4 years.However,microbial communities and biomass did not recover to the status of native vegetation even after 35 years of vegetation cover.A redundancy analysis and Pearson correlation analysis indicated that soil organic carbon,total nitrogen,available potassium,soil water content,silt content and soil hardness explained 98.4% of total variability in the microbial community composition.Soil organic carbon,total nitrogen,available potassium and soil water content were positively correlated with microbial community structure and biomass,whereas,soil hardness and silt content were negatively related to microbial community structure and biomass.This study provides new insights into microbial community structure and biomass that influence organic carbon,nitrogen,phosphorus and potassium accumulation,and clay content in soils at different stages of restoration.     

中亚热带森林转换对地表CH4氧化的影响

利用静态箱-气相色谱法对中亚热带常绿阔叶天然林与杉木人工林地表CH4氧化速率进行17个月的定位观测研究.结果表明:在观测期间(2009 - 04-2010 - 08),天然林与人工林均表现为大气CH4汇,天然林与杉木人工林地表CH4年均氧化速率分别为32.01和25.31 μg·m -2h-1,天然林地表CH4氧化速率为10.83 ～75.02μg·m -2h-1,人工林地表CH4氧化速率为7.66 ～46.40 μg·m-2h-1;地表CH4氧化速率受土壤温度、含水量及其交互作用的影响,土壤体积含水量显著影响地表CH4氧化速率,而土壤温度对地表CH4氧化速率的影响则因土壤体积含水量和土壤深度而异.     

基于探地雷达的根系探测对土壤含水量的响应

在探地雷达对地下根系进行探测和识别的过程中,土壤含水量是影响根系探测效果的一个极为重要的因素。本文在2种质地土壤(砂质壤土和粘土)不同水分含量下,通过探地雷达对根进行模拟试验,测定了2种质地土壤的电磁波波速,同时测试了根的探测效果。结果表明:土壤含水量是影响电磁波波速的主要因素,电磁波波速不受天线频率的影响,但随着土壤含水量的增大而减小。本研究建立了2种质地土壤的电磁波波速(ν)与土壤含水量(θ)的理论模型,经过验证:发现该模型测算的根深度可以用来评估根的实际深度;在2种质地土壤中,根的分辨率均表现为随土壤水分含量增大而减弱,2者差异较大;当含水量>20.33%(砂质壤土)或>26.82%(粘土)时,均不适宜利用GPR进行根探测。     

Impact of land use on physico-chemical and hydrological properties of ustifluvent soils in riparian zone of river Yamuna,India

Land use influences physico-chemical and water transmission properties of soil, which ultimately determine the suitability of land for different purposes. In present study, impact of different land use (forest and agriculture) on selected physicochemical and hydrological properties of soil was evaluated and compared with a reference site (uncultivated ravinous wasteland). Land use influenced infiltration rate, bulk density, mean weight diameter of aggregates and plant available water of soils. After 25 years of plantation of forest species, soil organic carbon content increased by more than twofold and mean weight diameter of aggregates by 2- to 6-fold in comparison to reference site. Significant reduction in soil bulk density (4–18%) and increase in steady state infiltration rate (1.5–2 times) was observed under the forest land use system. Conversion of ravine to forest system resulted in significant improvement in moisture retention capacity of soil. Conversion of ravine landform to agriculture adversely affected the soil bulk density and infiltration rate. The study provided practical information regarding rehabilitation potential of different tree species (Prosopis juliflora, Leucaena leucocephala, Acacia nilotica and Azadirachta indica) that could be used for restoration of ustifluvent soil susceptible to gully erosion in the semi-arid region.     

Rosellinia necatrix attack according to soil features in the Mediterranean environment

A study was carried out on Rosellinia necatrix attack on young woody plants, as possibly affected by selected soil features under three water regimes. Six different soil systems representing five agro‐environments and one forest in the Puglia Region (southern Italy – Mediterranean climate) were compared. R. necatrix attack on sweet cherry trees was simulated using artificial inoculum and saplings of Prunus mahaleb, the most widely used rootstock of sweet and sour cherries, monitored during the spring period. Soil features significantly influenced disease score, which did not differ from one water regime to another, even though disease level in the different soils was affected by water content. Rosellinia mahaleb saplings grown in forest soil showed the highest disease score, which differed significantly from that observed in all the agricultural soils tested in this study. Amongst these, disease score was lower in sandy soils than in soils that were richer in loamy fraction.     

Effects of soil type and water saturation on growth,nutrient and mineral content of the perennial forage shrub S<Emphasis Type="Italic">esbania sesban</Emphasis>

Sesbania sesban (L.) Merr is a perennial N₂-fixing tree with high potential for use in agricultural production systems as a green manure and livestock forage. We studied the interactive effects of soil type and water level on the growth, biomass allocation, nutrient and mineral content of S. sesban. Four-week old seedlings of S. sesban were grown for 49 days (n = 5) in a factorial mesocosm set-up with six soil types (sediment, sand, alluvial, acid-sulfate, saline and clay) and three water levels (drained, water-saturated and flooded). The soils tested represent the predominant alluvial soil types of the Mekong delta, Vietnam. Sesbania sesban grew well with relative growth rates (RGR) around 0.08 g g^?1 d^?1 in all studied soil types, except the saline soil where plants died. In the low-pH (3.9) acid sulfate soil, that constitute more than 40 % of the Mekong delta, the RGR of the plants was slightly lower (0.07 g g^?1 d^?1), foliar concentration of calcium was 3–6 times lower, and concentrations of iron and sodium up to five times higher, than in other soils. The nutrient and mineral contents of the plant tissues differed between the soils and were also affected by the flooding levels. Foliar concentrations of nitrogen (50–74 mg N g^?1 dry mass) and phosphorus (5–9 mg P g^?1 dry mass) were, however, generally high and only slightly affected by water level. The results show that S. sesban can grow well and with high growth rates on most wet soils in the Mekong delta, except saline soils where the high salt content prevents establishment and growth. The nutrient and mineral contents of the plants, and hence the nutritional value of the plants as e.g. fodder or compost crops, is high. However, soil type and water level interactively affect growth and tissue composition. Hence, optimal growth conditions for S. sesban differ in the different regions of the Mekong delta.     

有机覆盖物对城市绿地土壤含水量的影响研究

有机覆盖物是将废弃的树枝、树叶进行粉碎、加工,再覆盖于城市绿地中的有机物质。对覆盖有机物和未覆盖有机物土壤在雨后、干旱期、单位体积和单位重量含水量的测试说明,有机覆盖物对土壤含水量的保持具有显著的促进作用。     

Experimental studies on rain splash erosion of forest soils after clearing in Okinawa using an artificial rainfall apparatus

The main island of Okinawa, in southwestern Japan, is characterized by a subtropical climate, coral reefs, and reddish soils, which contain Acrisols and Cambisols (FAO/UNESCO classifications). Recently, due to soil erosion on hilly lands, the coral reefs have been damaged by an inflow of reddish soil. Forest clearing is thought to one of the factors increasing rain splash erosion rates on hilly lands, because it is believed that clearing disturbs the forest floor and causes the supply of litter to stop. After clearing, A0, A and B horizons will be denuded, one after the other, by rain splash. In this study, we measured rain splash erosion rates of undisturbed samples of A0, A and B horizons using an artificial rainfall apparatus. The results of experiments on rain splash erosion clarified several aspects of the erosion process in a clearing site. First, it was found that the rain splash erosion rates were higher in fresh litter than in decomposed litter, in decomposed litter than in the A horizon, and in the A horizon than in the B horizon. Thus, the erosion rate increases with soil depth. Secondly, surface-gleyed red and yellow soils are mostly vulnerable to rain splash erosion. The erosion rates of these soils are two to three times higher than those of the red soil and the yellow soils. Thirdly, the erosion rates are affected mainly by bulk density and saturated hydraulic conductivity, not by clay ratio and dispersion ratio. Lastly, the difference between erosion rates of surface-gleyed red and yellow soils and other soils will be even greater if a soil crust has formed, because the formation of a soil crust increases the rain splash erosion rate.     

海口地区木麻黄林根瘤调查及影响结瘤的因子探讨

木麻黄 (Ｃａｓｕａｒｉｎａｅｑｕｉｓｅｔｉｆｏｌｉａ)属双子叶植物纲木麻黄科木麻黄属。常绿乔木 ,高可达 30ｍ ,原产于澳大利亚 ,1 91 9年最早引种到福建省泉州 ,2 0世纪 5 0年代以后 ,广泛种植于东南沿海 ,特别是雷州半岛和海南岛 ,成为我国东南沿海和海南岛周边滨海地带