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1.
以北京市郊安达木河为研究对象,通过调查河流的生态特征、水文特征、地貌特征以及景观娱乐功能,在综合指数分析法的基础上,将集对分析的确定与不确定系统引入综合评价中,从相同、偏同差异、偏反差异、相异4个方面进行了分析,同时采用时间尺度和空间尺度相结合并着重从时间尺度上对评价结果进行分析。结果表明,近年来,安达木河局部河段生态环境遭到破坏,加强河流生态环境的治理,寻找农村垃圾合理有效的处理方式,减少不必要的人类活动对河流生态的影响,以及在发展旅游业和河流生态整治方面寻找平衡点,将成为下一步河流生态整治的重点内容。 相似文献
2.
生态河流构建原理与技术 总被引：11，自引：0，他引：11
传统的河流整治技术，如裁弯取直、疏开挖河道、浆砌石或混凝土加固河岸、高筑河堤等，忽略了河流的生态特性，结果导致河流水文发生改变，生态系统受到严重创伤。分析了河流治理技术的发展现状及遇到的问题，提出生态河流的概念，并探讨了生态河流的基本特征和构建原理，然后分别从河道景观设计、河道平面形态设计、河道断面设计和岸堤设计几个方面论述了生态河流构建的技术体系。最后，以镇江古运河生态岸堤构建为例，介绍了生态岸堤构建的实施办法，旨在探讨河流的生态治理的方法，实现人与自然和谐发展。 相似文献
3.
河流生态修复研究进展 总被引：2，自引：0，他引：2
在河流生态系统普遍遭受严重破坏的今天,河流生态修复成为研究的热点。该文在广泛查阅国内外河流生态修复资料的基础上,分析认为河流生态系统的影响因素主要为水文条件、流域气候、河流地貌、河流的水力特性和水质,以及人类活动在传统水利工程、污染物排放、过量引水及农渔业活动方面对河流生态系统的胁迫作用。在明确河流生态修复概念与任务的基础上,对河流生态修复理论研究中的河流健康、河流生态需水、河流生态修复尺度与机理,以及河流生态修复模型进行了分析与综述。对河流生态修复原则及生态修复中的几个重要技术问题进行了分析与评价。最后提出了我国河流生态修复研究和建设中应特别关注的几个问题及发展建议。 相似文献
4.
中国西北部生态脆弱区典型区域土地综合整治分区——以甘肃省兰州市为例 总被引：3，自引：0，他引：3
[目的]探讨土地整治规划的重要内容——土地整治分区,为确定土地整治重点区域和土地整治规划提供参考依据。[方法]以西北部生态脆弱区典型区域甘肃省兰州市为研究区域,基于生态保护视角,在充分考虑区域自然地理特征、土地利用特点及区域主要生态问题的基础上,从地形地貌、降雨、土壤类型、植被类型、水土流失、土地利用等5方面选取指标因子初步构建分区指标体系,并从水资源供给、水系分布及行政区划等方面进一步完善。同时运用ArcGIS空间叠加分析功能,使用综合分析法进行土地综合整治分区。[结果]形成了"方位+地貌+土地利用类型"命名的土地整治两级分区体系,二级分区较为详细。兰州市划分为7个一级区和15个二级区。[结论]中国西北部生态脆弱区域在土地综合整理过程中应该通过选择合理的指标体系分区进行整治。各分区应该针对其土地资源、水资源、生态环境状况等具体特征,基于生态保护视角采取有效措施进行土地综合整治。 相似文献
5.
娄利华 《水土保持应用技术》2024,(1):24-25
根据河流生态用水特征,选择河道未渠化率、污水处理率、植被覆盖率、透水表面率和河道疏浚频率5个指标,采用模糊物元法评价分析朝阳市2011—2021年城市河流生态用水效率。结果表明,经过近10 a整治朝阳市生态水系取得显著成效,但仍需加大河道生态景观、污水处理、绿化等投入,研究成果为城市河流生态治理及其用水效率评价提供了参考。 相似文献
6.
基于模糊矩阵法的河流健康评价体系 总被引：1，自引：0，他引：1
基于河流健康评估,针对威胁河流生态健康及河流治理的问题,提供关于河流健康及其问题河段的科学解释与依据。在综合国内外河流健康状况评价方法及各项表征指标的基础上,建立了基于模糊矩阵法的河流健康评价体系。应用模糊关系合成原理,从多个因素对河流隶属等级状况进行综合评判。具体评价时分为目标层、准则层和指标层,结合模糊矩阵采用层层推进的计算方法,最后将计算结果分为自然、近自然、退化、人工4大类。结果表明:怀沙河总体得分为2.6分,其中自然状态占整条河段的41%,近自然状态占整条河段的32%,退化自然状态占整条河段的27%。分段评价结果表明:三岔、渤海、口头河段状态较好,四渡河、南冶、辛营需要采用合理措施来改善河流生态系统。该评价方法可以针对性地提出改进措施和建议,为城市郊区河流的健康和生态环境建设的可持续性提供思路。 相似文献
7.
8.
城市内小流域综合整治及效益分析--以重庆市清水溪流域为例 总被引：3，自引：0，他引：3
城市内小流域是城市生态系统的重要组成部分。城市小流域的合理规划和综合整治,是城市水土保持和城市可持续的重要途径。清水溪是流经重庆市主城区的一条河流,流域污染严重,环境恶化,已严重影响城市形象,制约城市发展。本文在界定城市内小流域概念的基础上,对清水溪小流域综合整治的措施及环境效益进行了分析。认为城市内小流域的综合整治应以通过恢复小流域生态系统为目标;城市内小流域综合整治的效益分析,应从生态、经济和社会等几方面进行评价。 相似文献
9.
浅淡城市河流整治与生态环境保护 总被引：8，自引：2，他引：8
城市河流是城市生态系统的组成要素之一 ,其供水、环保、绿化、游乐等生态功能 ,已逐渐被应用到生态城市建设中。传统的用混凝土等硬化覆盖河岸的城市河流整治方法 ,已逐步被各国普遍否定 ,而建设生态河堤成为国际大趋势。城市河流整治应以保护、修复生态环境为前提 ,以建立良好的滨水环境为目的。 相似文献
10.
西苕溪是太湖上游的重要支流,由于人类活动的干扰,河流健康状况受损,功能下降。基于河流健康的内涵,选取河流形态结构、河流社会经济功能和河流生态功能3类诊断河流健康状况的1级指标。针对西苕溪流域健康现状和可获取的资料,构建了诊断西苕溪健康状况的18个2级指标。选用多目标多层次模糊模型诊断西苕溪健康状况,建立了各指标标准特征值,确定了各指标权重。计算和分析结果表明,西苕溪综合健康状况大部分处于中等和良好状态,河流形态结构的改变和较差的水质是影响其健康的主要原因。西苕溪流域的生态修复措施主要包括创建多样性生物栖息地,有效控制面源污染,建立水库适应性管理程序等。 相似文献
11.
低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响 总被引：2，自引：2，他引：0
【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。 相似文献
12.
Aleš Lebeda Ivana Doležalová Eva Křístková Barbora Mieslerová 《Genetic Resources and Crop Evolution》2001,48(2):153-164
Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions. 相似文献
13.
Kyle Devey Michael Mucalo Gordon Rajendram Joseph Lane 《Communications in Soil Science and Plant Analysis》2015,46(4):72-80
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing. 相似文献
14.
Thomas Larsen Jesper Luxhøi Jakob Magid Lars Stoumann Jensen Paul Henning Krogh 《Biology and Fertility of Soils》2007,44(1):59-68
We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization
and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition
with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the
decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots
with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass,
soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration,
N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially
(<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation
in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils,
indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but
the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation
for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community
performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea. 相似文献
15.
《中国生态农业学报》2014,(6)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
16.
《中国生态农业学报》2014,(7)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
17.
《中国生态农业学报》2014,(8)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
18.
M.A. Callaham Jr. J.M. BlairT.C. Todd D.J. KitchenM.R. Whiles 《Soil biology & biochemistry》2003,35(8):1079-1093
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils. 相似文献
19.
I.L. Boyd 《Biological conservation》2010,143(7):1664-1674
“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options. 相似文献
20.
Soil-profile distribution of primary and secondary plant-available nutrients under conventional and no tillage 总被引：1，自引：0，他引：1
Nutrient distributions under no tillage (NT) compared with conventional disk-and-bed tillage (CT) management in the warm, humid region of the southeastern USA need to be assessed so that future placement, quantity, and type of fertilizers can be altered, if necessary, to efficiently match crop demands. We determined soil-profile distributions of pH, N, P, S, K, Ca, Mg, Na, Zn, Fe, Mn, and Cu to a depth of 0.9 m at the end of 8.5 years of continuous CT and NT management on a Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas. Most dramatic changes occurred within the 0–0.05 m depth, where soil under NT had lower pH, Fe, and Cu than under CT, but greater P, K, Zn, and Mn. Greater P and K under NT than under CT also occurred below the till-zone (0.15–0.3 m). At a depth of 0–0.3 m, soil under NT contained greater amounts of extractable P, K, Zn, Fe, Mn, and Cu than under CT. Nitrogen fertilization had little effect on nutrient distributions, except resulting in greater extractable K at 0–0.05 m and greater nitrate at 0–0.15 m. Few changes in soil-profile distributions were observed for extractable S, Ca, Mg, and Na. Long-term continuous use of NT on this fine-textured, high-fertility (except for N) soil had no apparent adverse effects on nutrient distributions relative to CT, but enhanced conservation and availability of P, K, Zn, Fe, Mn, and Cu near the soil surface where crop roots proliferate. 相似文献