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1.
生物肥部分替代化肥对甘蓝(Brassica oleracea)养分吸收、光合作用以及品质的影响 总被引：2，自引：0，他引：2
采用大田试验,研究了化肥减量20%~40%、配施生物肥对春茬甘蓝(Brassica oleracea)生长、养分吸收利用、光合作用以及品质的影响。结果表明:与当地施肥量(底肥:N 139.2kg·hm-2,P2O5255kg·hm-2,K2O 93.6kg·hm-2;追肥:N 208.8kg·hm-2)相比,化肥减量并配施生物肥使甘蓝生长前期、后期的茎粗变小;对甘蓝的叶片数、冠幅投影面积无显著影响;叶片的气孔导度、净光合速率均与对照无显著差异;促进了甘蓝叶球生长,叶球中硝酸盐和可溶性固形物含量降低,Vc含量增加;甘蓝叶球、叶片和根系氮含量降低,氮在叶球分配的比例提高,在叶片、根系分配的比例降低。化肥减量并配施生物肥提高了幼苗株高、增加了茎粗,气孔导度和净光合速率升高,降低了硝酸盐和可溶性固形物含量、叶球氮含量和根系的钾含量。 相似文献
2.
目前灵芝等食药用菌大多采用阔叶树栽培,对林木消耗极大,以草代木成为了现今的栽培趋势,不仅解决了原料来源的问题,而且可有效地保护森林生态环境。实验菌株选自实验室杂交菌株中的7株和亲本2株,通过统计菌丝生长速度、子实体大小、产量等农艺性状,并运用分光光度法及高效液相色谱法分析成熟子实体有效成分的含量,筛选出适合菌草栽培的菌种。实验结果表明,菌株J-1/AL-12的产量最高,同时有效成分含量也相对较高。分析不同杂交菌株间及菌草灵芝与木屑灵芝间的灵芝三萜指纹图谱,发现不同菌株的三萜含量有差异,而不同原材料栽培的灵芝子实体其三萜指纹图谱无明显差异。 相似文献
3.
肥草协同调控下紫色土油茶园土壤肥力和油茶生长特征 总被引：1，自引：0，他引：1
《亚热带资源与环境学报》2020,(2)
为了评价不同调控措施对闽西紫色土油茶园土壤肥力和油茶生长的影响,本研究设计了有机肥+黑麦草+复合微生物肥+圆叶决明(T1)、复合肥+黑麦草+圆叶决明(T2)、复合肥(T3) 3种调控措施,以不采取任何调控措施的处理为对照(CK),对比分析不同调控措施下闽西紫色土油茶园土壤养分及油茶生长特征,并揭示油茶生长特征与土壤养分改良之间的关系。结果表明:试验1年后,T1的土壤全氮含量为CK的1. 13倍;土壤铵态氮与硝态氮含量均为T1、T2显著高于CK (P0. 05);土壤速效磷、速效钾含量均为T1、T2显著高于T3、CK (P0. 05),其中土壤速效磷含量分别为CK的3. 83、3. 56、1. 72倍,土壤速效钾含量分别为CK的2. 93、2. 93、1. 68倍。试验1年后,3种调控措施下油茶树的株高增量、地径增量、冠幅增量、新梢长、叶面积、叶绿素相对含量SPAD值均显著高于CK (P0. 05); 3种调控措施下油茶叶片的氮、磷、钾含量较CK有明显提高;油茶长势特征、叶片养分与土壤速效养分含量具有较强的相关性。可见,3种调控措施能提升油茶园紫色土肥力和促进油茶生长,其中T1、T2对紫色土肥力的调控效果更优。 相似文献
4.
栽培条件下甘草的甘草酸及多糖含量 总被引：1，自引：0，他引：1
通过对3年生相同人工栽培条件下的不同种甘草及2种不同栽培措施的乌拉尔甘草为分析样本,采用高效液相色谱和苯酚-硫酸比色法对其甘草酸及多糖含量进行测定,分析比较甘草酸与甘草多糖含量之间的相互关系,并筛选出乌拉尔甘草的最优栽培措施。结果表明：甘草酸含量顺序为乌拉尔甘草〉胀果甘草〉黄甘草〉光果甘草;多糖含量以光果甘草3．76％为最高,其余3个种间含量相差不大。正交试验的方差分析表明：（1）对于播种3年生乌拉尔甘草,以甘草酸含量为评价指标,最优栽培措施为：灌溉量4500m^3／hm^2、二铵0kg／hm^2、种子（对照）、尿素0 kg/hm^2、播种量90kg/hm^2;若以甘草多糖含量为获取目标,最优栽培措施为：灌溉量1500m^3／hm^2、二铵300kg/hm^2、种子（包衣,尿素0．5％浸泡24h）、尿素300kg／hm^2、播种量90kg/hm^2。（2）对于移栽3年生乌拉尔甘草,以甘草酸含量为评价指标,最优栽培措施为：灌溉量1500m^3／hm^2、移栽苗（对照）处理、二铵0 kg／hm^2、尿素0kg/hm^2、株距5cm;若以甘草多糖含量为评价指标,最优栽培措施为灌溉量3000m^3／hm^2、移栽苗（对照）处理、二铵150kg／hm^2、尿素300kg／hm^2、株距10cm。 相似文献
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利用2005年安排在临泽边缘绿洲沙地农田的长期施肥定位试验，研究不同用量有机肥、化肥、有机肥和化肥配施对绿洲沙地土壤肥力及有机碳积累的影响。试验包括高量有机肥单施（M3），氮磷化肥单施（NP3），低、中、高量氮磷钾化肥单施（NPK1，NPK2，NPK3），及低、中、高量氮磷钾化肥配施高、中、低量有机肥9个处理（NPK1M3，NPK2M2，NPK3M1），测定分析10年后不同施肥处理耕层（0~20 cm）土壤物理化学性状特征及有机碳动态。结果表明：施有机肥及有机无机配施处理较单施化肥处理容重下降0.13 g·cm-3，田间持水量提高6.7%，单施有机肥、有机无机配施较单施化肥，土壤有机碳（SOC）和全氮含量分别提高64.8%、36.3%和64.9%、49.5%。高量施用氮磷化肥和氮磷钾化肥处理全磷含量最高，有机肥及有机无机配施较单施化肥有效氮含量显著增加，有机无机配施及高量施用磷肥土壤有效磷积累明显，高量施用有机肥能显著提升有效钾含量。连续施肥处理10年后，SOC含量提高了1.68~2.84倍，土壤全氮、全磷、碱解氮及有效磷均有一定程度的提高，但单施化肥及有机肥与氮磷化肥配施有效钾含量下降。SOC的积累速率单施化肥、有机无机配施，单施有机肥处理分别为0.27、0.59，0.87 g·kg-1·a-1。增施有机肥、适量减少化肥投入、氮磷钾化肥的平衡施用是绿洲沙地农田土壤肥力持续提升的施肥管理对策。 相似文献
6.
由于具有提高沙土的稳定性和保水性等特征,复合高吸水性固沙材料在荒漠化土地治理方面具有一定的潜力和应用前景。研究了蓝藻结皮在不同比例凹凸棒基高分子固沙材料中的生长状态和生理特性。结果表明:蓝藻结皮与经4 mol·L-1硫酸改性后的凹凸棒基高分子固沙材料以1∶3质量比配比生长情况最佳;比较了复配材料喷洒量为400、500g·m-2处理下蓝藻叶绿素a、丙二醛、可溶性蛋白及可溶性糖含量等生理指标,喷洒量为500 g·5m-2的蓝藻结皮与经4 mol·L-1硫酸改性后的凹凸棒基高分子固沙材料生理特性较好。 相似文献
7.
九段沙上沙湿地植物钾元素的分布、积累与动态 总被引：5，自引：2，他引：3
2005年4～12月,逐月对长江口九段沙上沙湿地生态系统主要植物群落进行了定位样品采集与生态环境因子监测。通过对样品的分析化验,研究了该区典型湿地植物群落的海三棱蔗草（Scirpus mariqueter）、互花米草（Spartina alterniflora）和芦苇（Phragmites australis）3种植物中钾元素的空间分布特征和时间动态变化规律,揭示了上沙主要类型湿地植物钾元素的含量特征、分布、迁移与积累规律。结果表明：①上沙不同湿地群落植物钾元素的含量与分布规律存在差异,3种植物相比,叶、叶鞘和茎或秆的钾含量均以海三棱蔗草最高;果实和地下部分的钾含量以芦苇最高;叶和地下部分的钾含量以互花米草最低。3种植物果实钾含量的差异最大,地下部分钾含量的差异最小。海三棱蔗草叶的钾含量最高,其次为秆、叶鞘和根,果实的钾含量最低。互花米草茎的钾含量最高,其次为叶、果实、叶鞘与根,须根的钾含量最低。芦苇果实的钾含量最高,其次为叶、茎、根状茎与叶鞘,根的钾含量最低。②不同时期,植物钾元素贮量受钾元素含量和生物量的影响程度存在差异,但总体影响程度基本相当。芦苇钾元素贮量最高,互花米草其次,海三棱蔗草最低。3种植物叶的钾贮量差异最小,而地下部分的钾贮量差异最大。③植物中钾元素含量随植物生长发育过程而呈动态变化。不同植物以及不同植物构件中钾含量变化规律有明显的共性,3种植物总体表现为,随着生长进程,植物钾含量逐渐减少。植物生长初期,茎的钾含量最高,地下部分钾含量最低;旺盛生长期,叶的钾含量普遍比较高,最低值不一致;生长末期最后阶段,地下部分钾含量最高,叶鞘的钾含量最低。 相似文献
8.
砂蓝刺头(Echinops gmelini)是沙区常见一年生草本,具有繁殖比例高、密度高和生长速度快等特征,是研究区春季和早夏季节植物群落组成中最重要的草本植物。沙区人工植被演替过程中,群落中砂蓝刺头个体构件形态和生物量分配特征及其对土壤生境恢复的指示意义是本研究目的。分析了不同植被恢复阶段的沙地中(2010年铺设草方格、始植花棒、始植油蒿和1989年始植柠条与油蒿的固沙区,分别为生境1、2、3和4)砂蓝刺头构件形态及生物量分配特征。结果表明:(1)人工植被建立早期,初步稳定的沙面条件有利于砂蓝刺头的生长,而随着人工植被建立时间的增长呈现出种群衰退的趋势。4个生境间砂蓝刺头在株高、基径、根长、花序数及各器官生物量方面均差异显著(P<0.05),其大小关系是生境2>3>1>4。(2)不同生境地上-地下生物量间均为等速生长关系,且存在共同相关生长指数1.036,支持等速生长假说;地上-叶生物量间具有共同异速生长指数(0.874,异速生长关系);营养体-繁殖生物量间均表现出α>1异速生长关系,即繁殖生长资源的积累速率快于营养体生长。(3)株高、花序数与地上部分生物量间具有显著或极显著的正相关关系,表现出较好的协同变化趋势。总之,不同生境间砂蓝刺头形态结构及生物量特征具有明显差异,而构件生物量间相关生长关系的一致规律性及较稳定的繁殖生物量分配,有利于其适应异质生境并完成生长发育。 相似文献
9.
《中国沙漠》2019,(3)
解淀粉芽孢杆菌(Bacillus amyloliquefaciens)FZB42是一种植物根际促生菌(PGPR),能够促进植物生长,提高植物抵抗病害\,干旱和盐胁迫的能力。但关于干旱胁迫下解淀粉芽孢杆菌FZB42自身生物被膜形成能力及根际定殖能力的研究鲜见报道。利用PEG-6000模拟干旱胁迫,进行渗透势分别为-0.05、-0.50、-1.48、-2.95 MPa的干旱胁迫处理,测定分析此胁迫条件对解淀粉芽孢杆菌FZB42的生长、生物被膜的形成、根际定殖能力以及胞外多糖产量的影响,为进一步阐明解淀粉芽孢杆菌FZB42对提高植物的抗干旱能力提供理论依据。结果表明:(1)高浓度的PEG-6000能够显著抑制解淀粉芽孢杆菌FZB42的生长、生物被膜的形成及在拟南芥(Arabidopsis thaliana)根际的定殖能力。当添加15%PEG-6000时,生物被膜吸光度(OD_(600))和根际定殖数量达到最低值,分别为1.542和1 500 cfu·mm~(-1)。(2)解淀粉芽孢杆菌FZB42的胞外多糖分泌量随PEG-6000浓度的增加而增加。不添加PEG-6000时,胞外多糖含量最低为150.2 mg·L~(-1)。当添加15%PEG-6000时,胞外多糖的产量最高为568.8 mg·L~(-1)。 相似文献
10.
光周期对沙枣尺蠖病菌（Dh菌株）离体培养的影响 总被引：1，自引：1，他引：0
研究了光周期对沙枣尺蠖病菌（Emericella quadriclineata）Dh菌株菌丝生长及产孢量的影响。结果表明,光照对液培菌丝生物量和平板培养产孢有明显的影响,长光照有利于菌丝生长,菌丝生物量明显高于短光照和全黑暗;培养4 d菌丝生物量最大,其中以18 h光照与6 h黑暗交替菌丝生物量最大。光照对Dh菌株平板产孢具有一定的促进作用,连续光照与各温度组合的累积产孢量显著高于连续黑暗下各温度组合,以全光照25℃培养7 d产孢量最高,第3天至第5天时增长率达到顶点;30℃和35℃下无论是光照还是黑暗条件均不适合产孢,其产孢速率呈持续下降状态。紫外光对Dh菌株生长的影响程度与照射时间有关,在供试范围内,照射时间越长菌落生长越慢。 相似文献
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《The Professional geographer》1988,40(4):471-499
Books reviewed in this article: USA, Eine Geographische Landeskunde , Vol. I, Der Grossraum in Strukturellem, Wandel, 3rd Ed. Helmut Blume . Introduction to Remote Sensing . James B. Campbell . The Sounds of People and Places: Readings in the Geography of American Folk and Popular Music . George O. Carney , ED. Development and Underdevelopment . John Cole . Mobility and Employment in Urban Southeast Asia: Example from Indonesia and the Philippines . Michael A. Costello , Thomas R. Leinbach , AND Richard Ulack . Soviet Asia: Economic Development and National Policy Choices . Leslie Dienes . The Third World City . David Drakakis -Smith . Scholars' Guide to Washington, DC for Cartography and Remote Sensing Imagery (maps, charts, aerial photographs, satellite images, cartographic literature and geographic information systems). Ralph E. Ehrenberg . Population and Development in the Third World . Allan AND Anne Findlay . The Early Mapping of Hawaii . Gary L. Fitzpatrick . Energetics of Physical Environment: Energetic Approaches to Physical Geography . K. J. Gregory , ED. Wildland Recreation: Ecology and Management . William E. Hammitt and David N. Cole . Agricultural Commercialization and Government Policy in Africa . J. Hinderink AND J. J. Sterkenburg . The Dynamics of American Housing . James W. Hughes AND George Sternlieb . Thailand: Buddhist Kingdom as Modern Nation State . Charles F. Keyes . Resolving Locational Conflict . Robert W. Lake , ED. Lands at Risk in the Third World: Local-level Perspectives . Peter D. Little and Michael M. Horowitz , EDS. Nathaniel Southgate Shaler and the Culture of American Science . David N. Livingstone . Regions: The Economics and Politics of Territory . Ann R. Markusen . Wetlands . William J. Mitsch and James G. Gosselink . Historical Geography: Progress and Prospect . Michael Pacione , ED. Loess and Periglacial Phenomena . Marton P$eacsi and Hugh M. French , EDS. Regional Management of Metropolitan Floodplains, Experience in the United States and Abroad . Rutherford H. Platt , ED. Human Cartography: Mapping the World of Man . Janos Szegö . Atlas of Great Lakes Indian History . Helen H. Tanner , ED. The Botany of Mangroves . P. B. Tomlinson . Urban Spatial Traffic Patterns . Rodney Vaughan . The Night After … Climatic and Biological Consequences of a Nuclear War . Yevgeni Velikhov , ED. Industrial Geography . H. D. Watts . Dictionary of Quotations in Geography . James O. Wheeler and Francis M. Sibley . Vermont Townscape . Norman Wiliams , Jr. , Edmund K. Kellogg and Peter M. Lavigne . 相似文献
14.
P. Guilizzoni A. Marchetto A. Lami N. G. Cameron P. G. Appleby N. L. Rose Ø. A. Schnell C. A. Belis A. Giorgis L. Guzzi 《Journal of Paleolimnology》1996,15(3):245-264
A palaeoecological study of an oligotrophic alpine lake, Paione Superiore (Italy), provided a record of historical changes in water quality. Historical trends in lake acidification were reconstructed by means of calibration and regression equations from diatoms, chrysophycean scales and pigment ratios. The historical pH was inferred by using two different diatom calibration data sets, one specific to the alpine region. These pH trends, together with the record of sedimentary carbonaceous particles and chironomid remains, indicate a recent acidification of this low alkalinity lake.Concentration of total organic matter, organic carbon, nitrogen, biogenic silica (BSiO2), chlorophyll derivatives (CD), fucoxanthin, diatom cell concentration and number of chironomid head capsules increased during the last 2–3 decades. When expressed as accumulation rates, most of these parameters tended to decrease from the past century to c. 1950, then all except P increased to the present day. A marked increase in sedimentary nitrogen may be related to atmospheric pollution and to the general increases in output of N in Europe. High C/N ratios indicate a prevailing allochthonous source of organic matter.Finally, the increase in measured air temperature from the mid-1800's appeared to be related to lake water pH before industrialization: cold periods generally led to lower pH and vice-versa. The more recent phenomenon of anthropogenic acidification has apparently decoupled this climatic-water chemistry relationship. 相似文献
15.
K. F. Walker I. G. Dunn D. Edwards T. Petr H. Z. Yang 《International Journal of Salt Lake Research》1995,4(3):169-222
Quinghai Hu is a large, high-altitude, saline lake in north-western China, and supports a fishery based on an endemic species of naked carp (snow trout). The fish take seven years to attain maturity and a marketable weight of 300 g, and have a lifespan of 14–21 years under the present fishery regime. They seasonally migrate from the lake to spawn over the gravel beds of inflowing rivers, but these areas have been reduced by weirs and irrigation diversions and recruitment may have declined. The population may have been affected also by a 1.85-m fall in the lake level over the past 30 years, and by associated changes in salinity. The fishery was opened to large-scale exploitation in 1958. Yields declined sharply (max. 28,523 tonnes, 1960) as the larger, older fish were removed, and then more slowly (min. 2523 tonnes, 1983). Since 1987 the fish factory has been limited to an annual quota of 1200 tonnes, taken by a fleet of four pair trawlers. Another 800 tonnes are taken by licensed fishermen, mainly using gill nets, and perhaps 1000 tonnes are taken illegally. The estimated total catch in 1992 was 3000 tonnes. New trawlers introduced in 1989–90 substantially increased the factory's catch per unit effort, and in 1990 the quota was virtually filled in one month in a zone within 20 km of the factory. Although this could suggest that the stocks will be conserved if the quota is retained, at least half of the catch in 1989–92 consisted of immature individuals. Trawling operations recently were suspended following a further decline in the catch after 1992. While the new trawlers are capable of a major increase in effort, neither the changing environment, the fish stocks or the present markets favour intensified pressure. Gillnets may provide better control over the minimum size limit and may cause less damage than trawling. Other options to improve the viability and profitability of the fishery include improvements in handling, processing and marketing. Failure to develop the fishery may encourage attempts to introduce exotic fish, at some risk to survival of the local species. 相似文献
16.
17.
Chironomidae (Diptera) remains in surficial lake sediments from the Canadian Cordillera: analysis of the fauna across an altitudinal gradient 总被引：3，自引：0，他引：3
The altitudinal distribution of Chironomidae (Diptera) in the southern Canadian Cordillera was analyzed by means of head capsules preserved in surficial sediments of 30 lakes. Taxa characteristic of late-glacial deposits of southern, coastal British Columbia are extant at high elevations, particularly in the Rocky Mountains, and in large, deep, low-elevation lakes. Many chironomid taxa common at low elevations in the southern Canadian Cordillera were not found in alpine and upper subalpine lakes. These faunal differences are probably climatically related. The differences in fauna between high and low-elevation lakes parallel differences between arctic and temperate lakes. 相似文献
18.
MATT K. MATSUDA 《Geographical review》2007,97(2):230-243
ABSTRACT. Narratives concerning Pacific Ocean territories are often historically derived from European and American mainland visions of great, empty oceans dotted with deserted and uninhabited islands. However, research by indigenous and outlander scholars, along with struggles for political and cultural autonomy in the Pacific, has brought attention to vital island communities and 6has raised questions about a Pacific‐island way of understanding the world. This understanding is traced through scholarly and artistic engagements with history, island‐community studies, and navigational philosophies and is framed by a growing theoretical literature on epistemologies of place from the disciplines of geography and oceanography. 相似文献
19.
Precipitation is an important component of global water and energy transport and a major aspect of climate change. Due to the scarcity of meteorological observations, the precipitation climate over Tibet has been insufficiently documented. In this study, the distribution of precipitation during the rainy season over Tibet from 1980 to 2013 is described on monthly to annual time scales with meteorological observations. Furthermore, four precipitation products are compared to observations over Tibet. These datasets include products derived from the Asian Precipitation-Highly-Resolved Observational Data(APHRO), the Global Precipitation Climatology Centre(GPCC), the University of Delaware(UDel), and the China Meteorological Administration(CMA). The error, relative error, standard deviation, root-mean-square error, correlations and trends between these products for the same period are analyzed with in situ precipitation during the rainy season from May to September. The results indicate that these datasets can broadly capture the temporal and spatial precipitation distribution over Tibet. The precipitation gradually increases from northwest to southeast. The spatial precipitation in GPCC and CMA are similar and positively correlated to observations. Areas with the largest deviations are located in southwestern Tibet along the Himalayas. The APHRO product underestimates, while the UDel, GPCC, and CMA datasets overestimates precipitation on the basis of monthly and inter-annual variation. The biases in GPCC and CMA are smaller than those in APHRO and UDel with a mean relative error lower than 10% during the same periods. The linear trend of precipitation indicates that the increase in precipitation has accelerated extensively during the last 30 years in most regions of Tibet. The CMA generally achieves the best performance of these four precipitation products. Data uncertainty in Tibet might be caused by the low density of stations, complex topography between the grid points and stations, and the interpolation methods, which can also produce an obvious difference between the gridded data and observations. 相似文献
20.
Jean-Claude Plaziat 《Journal of Paleolimnology》1993,8(2):163-169
Potamids generally live in estuaries, lagoons, and along protected sea shores. However, their ability to colonize intracontinental lakes has been underestimated due to non- or misidentifications. Potamides conicus, the only present lacustrine Potamid currently found in North Africa, belongs to a lagoon-type (thalassoid) malacofauna, dominated by the Cardium Cerastoderma glaucum: this fauna occurs in association with Foraminifera (especially Ammonia beccarii) and Ostracoda (Cyprideis gr. Torosa). Potamids have been found 250 to 900 km from the nearest sea shore: passive dispersal (probably through birds) is the primary dispersal mechanism. Shell morphology and ornamentation can be used to characterize life environment (lacustrine versus marine) but not distance from sea shore. The presence of Potamid-Foraminifera fauna in the fossil record has been interpreted as providing evidence for a sea connection (e.g., gulfs, lagoons). However, more recent paleoecological studies have demonstrated that such assemblages span an ecological gradient from freshwater to hypersaline lacustrine environments. Thus, the occurrence of modern Potamids in lacustrine (in addition to maritime) environments has important implications for Quaternary and Tertiary paleogeographic investigations. Lacustrine Potamids have been recorded from the European Tertiary (France, Spain) and from the Sahara Holocene. More research is required for the better understanding of the distribution and ecology of Potamids in modern and fossil lakes of other continents.This publication is the fifth of a series of papers presented at the Conference on Sedimentary and Paleolimnological Records of Saline Lakes. This Conference was held August 13–16, 1991 at the University of Saskatchewan, Saskatoon, Canada. Dr Evans is serving as Guest Editor. 相似文献