新疆螳螂 在营养缺失的地带

<正>新疆荒漠属于亚-非荒漠区的一部分,荒漠构成复杂,多以灌木乔木为主。草原面积大,主要为山地草原、湖区草原和平原草原。这种环境导致分布在新疆的螳螂种类屈指可数,但都特点鲜明,具有适应干旱荒漠环境的行为习性。薄翅螳,交配结束前雄性被雌性啃掉半个身子薄翅螳,属螳螂目下螳科、螳亚科的螳属,是分布非常广泛的种类,从欧洲、     

白刺资源保护及锁阳集约化经营技术

一、锁阳和白刺的特性 锁阳是锁阳科锁阳属多年生肉质草本植物,寄生于白刺的根部。学名锁阳,俗名不老药、锈铁棒、地毛球、黄骨粮、铁严子等。野生锁阳生于荒漠草原、草原化荒漠与荒漠地带。多在轻度盐渍化低地、湖盆边缘、河流沿岸阶地、山前洪积、冲积扇的扇缘地生长,土壤为灰漠土、棕漠土、风沙土、盐土。多分布于甘肃、新疆、内蒙古、青海、宁夏等地的戈壁和沙漠。     

保护和发展荒漠梭梭林

梭梭林,是在干旱荒漠气候条件下,经过漫长的历史演变所形成特有的荒漠灌木林.它属亚洲中部荒漠植被类型,是荒漠生态系统中能量变换与物质循环的主体.在一定意义上说又独自成为荒漠梭梭林生态系统.梭梭是一种灌木或小乔木.在我国内蒙、宁夏、甘肃、青海和新疆等省(区)均有分布,准噶尔盆地是新疆梭梭林的分布中     

筑牢阴山北麓草原生态安全屏障 推动牧区经济社会高质量发展

<正>包头市草原面积辽阔，占全市总土地面积的68%，其中达尔罕茂明安联合旗（以下简称“达茂旗”）草原占包头市总草原面积的83.41%。在阴山北麓形成了从东向西、从南向北，由典型草原向荒漠草原和草原化荒漠过渡的草原类分布格局，荒漠草原和草原化荒漠占全旗草原面积50%以上，属于半干旱农牧交错地区，生态本底十分脆弱，加之气候变暖趋势明显，     

适境而生的植物：广阔天地里的变脸——草原植物

草原是温带半湿润地区向半干旱地区过渡的一种由低温旱生多年生草本植物组成的地带性植被类型。在世界上分布有两大区域，即欧亚草原区和北美草原区。我国草原属欧亚草原区一部分。主要分布在内蒙古自治区和大兴安岭以西的广大地区，自东向西依次递交为草甸草原地带、典型草原地带和荒漠草原地带。     

达茂旗腾格淖尔红柳林区啮齿动物的调查初报

天然红柳林Tamarixramosessima在内蒙古主要分布于西部的荒漠草原和荒漠的部分地区 ,是重要固沙植物。在腾格淖尔 ,除了有红柳盐生灌丛群落 ,其外部还分布着盐爪爪盐生荒漠群落、白刺盐化荒漠群落、芨芨草盐化草甸群落、红砂草原化荒漠群落 ,它们是在盐渍土上形成的荒漠植物群落。由于鼠类的危害使其正常生长发育受到影响 ,甚至死亡。 2 0 0 2年 6月对达茂旗腾格淖尔天然红柳林区的啮齿动物进行了调查 ,调查面积 10 0hm2 。对于夜间活动的啮齿动物采用夹线法 ,即每条夹线布放 5 0只标准板铗 ,行距 5 0m ,铗距 5m ,用白面、素油和在一起作饵…     

我国北方荒漠草原退化研究进展

针对近年来内蒙古地区荒漠草原严重退化的生态问题,文章归纳总结了内蒙古荒漠草原及其退化面积概况,综述了关于内蒙古荒漠草原退化表现及影响因素、荒漠草原退化监测及评价体系以及荒漠草原退化治理对策,并在此基础上分析认为:目前关于荒漠草原退化研究多集中在荒漠草原退化现状、荒漠草原退化影响因素以及退化不同阶段植被及土壤特征等方面,而在荒漠草原退化监测及评价、荒漠草原退化过程机理、荒漠草原生态重建的方法及技术体系方面具有很大改进余地及深入研究价值。     

黑沙蒿的优良特性与开发利用

一、黑沙蒿的分布 黑沙蒿,又名沙蒿、油蒿、鄂尔多斯蒿,分布范围跨越了典型草原、荒漠化草原和草原化荒漠3个自然带。据西北水土保持生物土壤研究所调查,沙蒿在西北和内蒙古西部地区分布面积达37,500万亩。     

新疆鸟类资源介绍〈一〉

新疆地处祖国的大西北,地域辽阔,环境多样,鸟类资源丰富。据调查有340多种,约占全国鸟类总数的三分之一。这些种类繁多,形态各异的鸟类,有的栖息、繁殖于森林、草原;有的生活在荒漠、半荒漠;有的分布在高山、水域,有些则飞翔于城镇、乡村上空,与人类结伴。它们装扮了祖国的河山,给人类带来了无穷的乐趣。     

新疆天燃胡杨林的开发利用和经营管理的探讨

胡杨分布地区甚为广泛,在我国,以新疆分布面积最大,数量最多,尤其是在南疆的塔里木河流域和叶尔羌河、喀什河的下游,分布最广,发育最茂密.新疆地区的胡杨,是一项宝贵的荒漠森林资源.在全疆范围内,除北部额尔齐斯河流域部分平原、丘陵地带少见生长外,几乎所有荒漠戈壁平原河沟两岸地区都有它的踪迹.由于它在塔里木河流域面积大,木材蓄积量丰富.因此,成为新疆三大自然林区之一.     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.     

CAD与建筑设计的关系

本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。     

Natural Regeneration in Clear-cuts: Effects of Scarification,Slash Removal and Clear-cut Age

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.     

Risk Perception Among Non-industrial Private Forest Owners

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.     

Interactions in decomposition and N mineralization between tropical legume residue components

In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.     

Pasture production and tree growth in a young pine plantation fertilized with inorganic fertilizers and milk sewage in northwestern Spain

The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha⁻¹ target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha⁻¹. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹); (2) Lolium perenne L. var. Tove (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m², with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.