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1.
辽阳市位于辽宁中部城市群的中心,水资源总量11.22亿m3。现有各类供水工程3 711处,其中蓄水工程9处,引水工程59处,提水工程26处,调水工程8处,水井工程3 616眼。2009年辽阳市供水量13.18亿m3。开发利用存在的问题:水资源贫乏,区域水资源开发潜力有限;水污染严重,水生态安全受到影响;水资源利用效率偏低,用水浪费现象严重;地下水超采,引发一系列严重的水环境问题;经济社会发展用水需求加大,未来城镇缺水形势严峻。建议搞好水资源的科学规划;加快节水型社会建设,提高水资源利用效率;强化水资源保护,改善水生态环境质量以节水配置为主线,严格水资源管理制度。  相似文献   

2.
以柳河流域阜新段为例,全面研究了其水质状况以及污染趋势.结果发现:柳河流域阜新段水质污染严重且水资源较为短缺,主要污染物浓度快速增长导致水质恶化速度加快,然后结合区域实际情况提出有针对性的污染防治对策,可为柳河流域水污染治理以及水资源合理开发利用提供一定参考.  相似文献   

3.
宁夏水资源可持续利用的理性思考   总被引:1,自引:0,他引:1  
宁夏水资源极度短缺,严重制约经济发展,依据水资源可持续利用的思想,从农业用水、工业用水、生活用水和水务管理四个方面分析了宁夏的水资源现状,对其现状进行理性思考并提出了对策,即实体水和虚拟水策略的联合运用、节水型社会构建及水务科学管理模式构建,其中实体水和虚拟水的联合调度包括“四水”的联合调度和虚拟水战略在宁夏的运用。  相似文献   

4.
沈阳区域水资源动态变化及可持续利用对策   总被引:1,自引:0,他引:1  
21世纪是全球水资源供需矛盾空前尖锐的时代.水资源短缺成为经济社会可持续发展的重要制约因素已经在许多区域凸显出来。沈阳是缺水地区之一,人均占有水资源量仅4876m^3,约是全国人均占有量的1/5。分析了沈阳区域水资源的动态变化、水资源的利用现状。提出了区域水资源可持续利用的对策,为政府进行水资源宏观调控和工程建设决策提供科学依据。  相似文献   

5.
山西省是我国严重缺水省份之一,针对其水资源总量较少、分布不均和流失严重的总体特点,结合其水利建设现状,系统分析了水资源污染、浪费、超采等问题,探讨了水资源可持续发展的对策。  相似文献   

6.
开发利用水资源改善西北生态环境   总被引:1,自引:0,他引:1  
西北地区水源枯竭,用水浪费,水体污染严重、水资源严重短缺,是制约西北区域经济发展关键因素,提出合理利用天然降水资源,经济可行,是水资源科学利用的一个途径;全民节水,科学配水,建设节水型社会,是合理利用水资源的一个侧面;理顺管理关系,优化配置水资源,综合治理,确立生态农业,涵养水分,改善生态环境,是水资源科学管理的有效途径,启动南水北调工程,是解决西北地区水资源短缺、改善生态环境的战略之计,通过以上途径,开发利用水资源,改善西北生态环境,支持区域经济可持续发展。  相似文献   

7.
基于2009年自然、社会经济以及水资源相关数据,选取水资源利用率、缺水率、灌溉率、降水量、人均占有水资源量、生态用水率6个指标作为评价因素,应用模糊综合评判模型,对北方八省市水资源承载力进行了研究。结果表明,该研究区综合评分值高于0.570,水资源开发已有一定规模,但仍有一定潜力,水资源供给在一定程度上能满足区域发展需要。对8个评价子区域而言,承载力状况差异很大,北京、天津、河北(京津冀)水资源承载能力比较脆弱,而山西、内蒙古、辽宁、山东、河南水资源承载能力相对较强,最后针对不同地区的水资源承载状况,提出了相应的措施。  相似文献   

8.
西部干旱半干旱地区水资源合理利用问题探讨   总被引:5,自引:0,他引:5       下载免费PDF全文
中国西部干旱半干旱地区约占全国土地面积的37.1%,降水稀少,蒸发量大,具有独特的水资源特征。该区域水资源的开发利用面临水资源短缺、地下水超采、地下水位下降、荒漠化加剧、水资源污染严重等问题。要合理开发利用该区域水资源,可考虑实施水资源管理战略,提高公众环境意识,并综合运用行政、经济、法津等手段,确保水资源的可持续利用。  相似文献   

9.
通过对自然集雨区水分动态10年定位观测研究,初步明确了我国亚热带丘岗区生态系统水资源的分布特征与水平衡状况。该区域雨水丰沛,总量可维持系统水分平衡,但其时空变化大,加之蒸发变化与之错位和土壤持蓄水分性能差等因素作用,导致系统水分盈亏现象发生,水分“高盈期”的湿害和“亏缺期”的伏旱严重制约了丘岗区农业的发展。强化工程、农艺措施调控能力,提高农业水资源管理水平,是促进我国亚热带丘岗区农业持续稳定发展的技术保障。  相似文献   

10.
亚热带丘岗区生态系统水平平衡及农业反应   总被引:2,自引:0,他引:2  
通过对自然集雨区水分动态10年定位观测研究,初步明确了我国亚热带丘岗区生态 系统水资源的分布特征与水平衡状况。该区域雨水丰沛,总量可维持系统水分平衡,但其时空变化大,加之蒸发变化与之错位和土壤持蓄水分性能差等因素作用,导致系统水分盈亏现象发生,水分“高盈期”的湿害和“亏缺期”的伏旱严重制约了丘岗区农业的发展。强化工程、农艺措施调控能力,提高农业水资源管理水平,是促进我国亚热带丘岗区农业稳定发展的技  相似文献   

11.
【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.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
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.
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   

19.
Abstract

A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species.  相似文献   

20.
Potassium (K) fixation and release in soil are important factors in the long-term sustainability of a cropping system. Changes in K concentration and characteristics of K fixation and release in rhizosphere and nonrhizosphere soils in the rapeseed (Brassica napus L.)–rice (Oryza sativa L.) rotation were investigated using a rhizobox system. The concentrations of different forms of K in both rhizosphere and nonrhizosphere soils decreased with plants compared to without plants, regardless of K fertilizer application. Potassium uptake by crops mainly came from the rhizosphere soil. In the treatment without K fertilizer (–K), the main form of K supplied by the soil to the crops was 1.0 mol L?1 nitric acid (HNO3) nonextractable K, followed by nonexchangeable K, and then exchangeable K. In the treatment with K fertilizer (+K), the main K forms supplied by the soil to the crops were exchangeable K and nonexchangeable K. The amount and rate of K fixation after one cycle of the rapeseed–rice rotation was greater in rhizosphere soil than in nonrhizosphere soil. The amount and rate of K fixation of soil in the +K treatment were significantly less than in the –K treatment. The cumulative amounts of K released with 1.0 mol L?1 ammonium acetate (NH4OAc) and 1.0 mol L?1 HNO3 extraction increased with the increasing numbers of extractions, but the K-releasing power of soil by successive extraction decreased gradually and finally became almost constant. The release of K was less in rhizosphere soil than in nonrhizosphere soil. The release of K in the +K treatment was similar to that in the –K treatment in rhizosphere soil, but the K release in nonrhizosphere soil was greater with the +K than the –K treatment. Overall, the information obtained in this study will be helpful in formulating more precise K fertilizer recommendations for certain soils.  相似文献   

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