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1.
黑河中游河道生态环境需水量研究 总被引：1，自引：0，他引：1
在黑河流域水资源开发利用过程中,人们只重视河流的经济效益而忽略了河流系统的生态环境需求,导致严重的生态环境问题随之而生.为了减少水资源开发利用过程中的生态环境问题,提出河道生态环境需水量的概念和计算方法,计算结果显示:黑河流域河道生态环境需水量为10.44亿m3/a,其中莺落峡生态环境需水量为4.755亿m3/a,约占河流地表水资源来水量的30%,正义峡生态环境需水量为3.06亿m3/a,约占河流地表水资源来水量的30%.考虑到其他因素.实际的生态环境需水量可能比计算结果要大.研究结果表明:黑河流域水资源利用率非常高,如何调控水资源开发利用,减少潜在生态环境问题是当务之急. 相似文献
2.
针对地下水资源可持续利用与表生生态协调发展的问题,在对天山北麓野外调查及已有研究结果分析的基础上得出细土平原区生态水位埋深为3～6 m。应用数值模拟技术对现状及调整开采布局后地下水位引起的表生生态效应进行对比,结果表明:现状地下水资源开发布局不仅易诱发表生生态负效应,而且造成了水资源浪费;通过调控地下水状态可以实现地下水资源可持续利用与表生生态协调发展的目的,并确定了不同地貌单元地下水开采阈值即山前戈壁带、细土平原区和沙漠边缘分别为7.3亿m3/a,16.4亿m3/a和2.4亿m3/a。 相似文献
3.
由于喀斯特流域独特的水文地质条件,其枯水也较非喀斯特流域不同,以贵州省为例,从喀斯特水文地貌学的角度,系统定义了喀斯特枯水,并分析了喀斯特流域枯水的特征和影响,提出了相应的开发利用措施,为以后的开发利用提供借鉴。 相似文献
4.
5.
泾惠渠灌区水环境劣变特征及地下水调蓄能力分析 总被引：7，自引：7，他引：0
为确保泾惠渠灌区水环境安全及地下水资源的可持续开发利用,该文通过对20世纪80年代以来泾惠渠灌区地表水和地下水环境劣变特征分析,重点指出了灌区地下水环境劣变的严重性,同时也证实了对地下水实施涵养调蓄的必要性。从取水条件、地下库容、蓄水水源和蓄水方式4个方面论证了灌区具备良好地下水调蓄能力,并利用体积疏干法对灌区各测站的地下调蓄库容进行计算,确定出灌区最大调蓄库容达6.46亿m3,年调蓄库容0.281亿m3。提出对灌区春、夏两季适当加大地表灌溉力度,并针对调蓄空间较大的石桥、泾阳等站进行优先调蓄,实现灌区“以井补渠,以渠养井”,即涵养了当地地下水资源,又有利于灌区水资源的可持续利用,最终保障了灌区的生态环境及粮食安全。 相似文献
6.
引黄灌区水资源联合利用耦合模型 总被引：9，自引：6，他引：3
随着引黄水量日益减少,如何有效利用有限的地表水和地下水,成为内蒙河套灌区亟待解决的问题。该文以引黄水量最小和地下水开采量最大为目标,以控制各用水区地下水位在适宜范围作为约束条件,通过动态耦合地下水模拟模型与地表地下水联合利用优化模型,建立了灌区水资源联合利用耦合模型,最后应用此耦合模型对灌区2020和2030年的引黄水和地下水进行了优化分配。结果表明：通过合理调整产业结构和有效利用地表地下水,灌区2020和2030年的引黄水量分别为39.15、38.54亿m3/a,可以达到国家规定的40亿m3/a指标。研究成果可为黄河流域乃至全国其它干旱灌区的水资源高效利用、盐碱化防治等方面提供借鉴和参考。 相似文献
7.
《山西水土保持科技》2019,(4)
地下水是寿阳县的主要供水水源。据统计,2016年地下水开采量1 428万m3,开发利用程度高达85%。由于高强度利用,地下水位年均下降0.34 m,累计已下降3.06 m。为给县域社会经济持续发展提供强有力的水支撑,根据水资源分布、开发利用状况及水质现状,提出了地下水资源分区保护目标和具体措施。 相似文献
8.
基于MIV-BP型的喀斯特地区水资源安全影响因素分析 总被引：1，自引：0，他引：1
[目的]分析喀斯特地区水资源安全的影响因素及其影响趋势,提出促进喀斯特地区水资源安全的措施与建议。[方法]采用贵州省近10a的数据,建立BP型网络模型计算平均影响值(mean impact value,MIV),对其影响因素进行实证分析。[结果]地下水供水比例、工业用水率、水资源利用率、人均粮食产量以及产水模数是水资源安全的阻碍因素。其中产水模数的影响程度呈现波动中逐年递减趋势,其余4个阻碍因素影响程度均显示逐年增强;工业固废综合利用率、工业废水排放达标率、中度以上石漠化面积比、单位GDP需水量以及地下水开发利用程度共同构成了水资源安全的驱动因素。从时间顺序来看,单位GDP需水量和地下水开发利用程度的影响趋于稳定,中度以上石漠化面积比因子对水资源安全影响越来越显著。工业废水排放达标率的影响逐年减弱,而工业固废综合利用率的影响情况波动比较大。[结论]模型计算表明,MIV-BP模型在喀斯特地区水资源安全影响因素研究方面具有一定的现实可行性。 相似文献
9.
摸清中国南方石漠化地区的畜禽粪便资源能源化底数,构建禽畜粪便资源的能源化利用模式,对于提高喀斯特森林生态系统服务功能、能源生产与消费革命等具有极强的现实意义。该研究以中国南方喀斯特石漠化问题严重的贵州省为研究区,以贵州省9个市/州的统计年鉴为数据来源,运用数理统计方法对贵州省4类畜禽粪便资源量、人均禽畜占有量等进行潜力估算,明确了贵州省畜禽资源地域性特征,揭示了贵州省畜禽粪便资源量在喀斯特县和非喀斯特县差异性,以及与石漠化等级之间的关联性,提出禽畜粪便资源能源化利用的生物天然气模式,测算了该模式的环境、社会和经济可行性。结果表明,2017年贵州省4类畜禽粪便理论资源量5 287.40万t,可收集资源量为3 635.86万t,牛粪和猪粪占绝对优势;空间上呈现东南向西北增长趋势,县域差异显著;肥料化资源量为1 815万t,可能源化资源量为1 820.86万t;以禽畜粪便为原料的沼气工程模式在高原山地潜在-轻度石漠化地区具有良好的经济性和可行性,巩固了石漠化治理成效且增加了农户健康和福祉。 相似文献
10.
贵州省是我国西南部喀斯特地区的典型代表,蕴藏着丰富的生物、矿产、水能和旅游资源,但突出的人地矛盾、脆弱的生态环境、恶劣的气候及落后的生产习惯严重制约着它的可持续发展。在深入分析贵州喀斯特地区的资源优势与制约因素的基础上,提出了加大生态建设力度、调整产业结构、加快科技创新步伐等适合贵州喀斯特地区可持续发展的战略建议,对贵州喀斯特地区乃至我国整个西南喀斯特地区资源的可持续开发利用具有一定的参考价值。 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.
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
19.
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
20.
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