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1.
Kern Ewing 《Estuaries and Coasts》1986,9(1):49-62
Environmental characteristics were measured and recorded in the Skagit Marsh, a brackish intertidal marsh on Puget Sound, Washington. Four transects were placed perpendicular to a known gradient of increasing salinity which began with fresh water at the bank of one of the outlets of the Skagit River and reached a surface water salinity of 22‰ at a point alongshore 5 km north of the outlet. The environmental characteristics which were measured varied along gradients (soil texture, organic carbon in fines, soil column temperature, free soil water salinity) or had a patchy distribution (soil redox potential, soil macro-organic matter). Growth and production vary across the marsh. The maximum aboveground standing crop (1,742 g m?2 dry weight) was measured at a site with 0–4‰ free soil water salinity, dominated by the sedgeCarex lyngbyei. In more saline areas (8–12‰), the bulrushScirpus americanus was dominant and standing crop values dropped to a third of the maximum. Species performance varied in a complex manner as did the environment.C. lyngbyei had diminished growth and decreased standing crop in areas where salinity was higher.S. americanus was equally productive in low elevation, high salinity sites and in high elevation, low salinity sites. An increase in shoot density for dominant species occurred in saline areas as individual shoot weights and leaf areas decreased. Because species responded differently, environmental variation was magnified in the population and community responses of the marsh vegetation. 相似文献
2.
The results of a study of soil factors in relation to plant growth for a tropical mangrove forest in northern Australia are presented and discussed. Basic soil properties are described briefly in terms of particle size distribution, bulk density and total carbon, nitrogen and phosphorus. Soil redox potential, pH, salinity and extractable nitrogen and phosphorus were monitored monthly over a 14 month period commencing April 1979. Sampling was carried out at 9 sites along a 370 m transect which exhibits strong gradients in topography, above ground biomass, canopy height and species distribution. Statistical analysis of the data shows that above ground biomass correlates significantly with the following soil factors, averaged over depth within the rooting zone and over time: Extractable P (r=0.85, p<0.01), redox potential (r=0.89, p<0.01) and salinity (r=?0.79, p<0.05). The strong biomass-EH correlation may be partly due to oxygen translocation by the plants to the root zone. Soil ammonium levels were within the range of 1–14 μg N per g (dry wt) and, unlike the above parameters, showed only minor variation with position along the transect. Variation of ammonium levels with time was apparent, but no significant correlation with rate of new shoot growth could be demonstrated, although depth profiles indicated depletion of ammonium by plant uptake during rapid growth periods. In addition neither soil ammonium, extractable phosphorus nor rate of plant growth showed any definite seasonal periodicity in this tropical system. 相似文献
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4.
B. Zaman B. H. Niazi M. Athar M. Ahmad 《International Journal of Environmental Science and Technology》2005,2(1):7-12
Wheat being a glycophyte crop, responds differently to saline-sodic soil environmental conditions. The application of calcium is multidimensional with respect to sodium ion and plant part response. This study was conducted to record the response of shoot and root to sodium and calcium interaction under saline environment. Wheat seed of variety Punjab 85 were raised in quartz sand. Later on the seedlings were transplanted to pots containing Hoagland’s nutrient solution along with NaCl at 0 mM. and 50 mM. Calcium was applied as CaSO2 2H2O at 3 mM. and 6 mM. Under saline conditions shoot showed positive response to sodium ion in the presence of higher calcium. Relative water contents were higher in the root system at 6 mM of CaSO4. 2H2O under saline condition. Growth responses to potassium and Magnesium in the presence of sodium induced salinity with calcium ion interaction remained variable. 相似文献
5.
【研究目的】为仁怀市农业生产中土壤养分的合理利用、农业结构调整及土地利用价值的提升等提供科学依据。【研究方法】本文利用电感耦合等离子体发射光谱法、容量法及电位法获取了5486件表层土壤样品氮磷钾（全量和有效态）及有机质的含量，系统研究了其地球化学特征及含量影响因素。【研究结果】仁怀市耕地土壤氮、磷、钾、有机质、碱解氮、速效磷及速效钾的平均值分别为1.74 g/kg、0.75 g/kg、19.90 g/kg、30.90 g/kg、100.28 mg/kg、10.40 mg/kg和101.03 mg/kg。其中，氮、碱解氮、磷、钾及有机质的含量及分布与地层关系密切；速效磷及速效钾的含量及分布与地层关系较差。仁怀市耕地土壤肥力较好，以较丰富等级为主，较丰富及丰富等级占比为57.6%。其中，氮、磷及钾皆处于丰富水平；碱解氮及有机质处于中等水平；速效磷及速效钾处于缺乏水平。【结论】仁怀市耕地土壤养分的含量及分布不仅受地质背景、土壤类型、海拔高度、酸碱度及土壤深度等自然因素影响，还与土地利用方式等人为活动有关。创新点：系统统计了仁怀市耕地土壤氮磷钾（全量和有效态）及有机质的含量，对其地球化学等级开展了评价，并系统分析了它们的含量影响因素。耕地土壤养分的含量及分布不仅受地质背景、土壤类型等自然因素影响，还与土地利用方式等人为活动有关。 相似文献
6.
Y. Ali Z. Aslam G. Sarwar F. Hussain 《International Journal of Environmental Science and Technology》2005,2(3):223-228
Wheat cultivars of diverse origin including approved varieties of different provinces of Pakistan i.e. Punjab, NWFP and Sindh were tested against different salinity levels in laboratory as well as in naturally saline fields in different ecological zones. Initially, 16 genotypes were studied for germination test at 6 different salinity levels ranging from 0–25 dS/m (2, 5, 10, 15, 20, 25, EC= dS/m). Then, out of 16 cultivars, 11 were studied for the relative growth rate at different levels of salinity and after their study in the laboratory, 9 genotypes were selected for testing in the naturally saline areas of Punjab province. Under germination percentage study, the varieties viz. Pasban-90, Sarsabz, Bakhtawar, 93032 and 933118 were less affected than other varieties. As regards the relative plant growth, varieties viz. Sarsabz, Bakhtawar, and Pasban-90 were tolerant to salinity at seedling stage while Inqlab was graded as sensitive to salt stress. Regarding field performance, significant differences were observed in the varieties grown under different saline environments and varieties x environment interaction. Varieties x environment (Lin) interaction was non significant while nonlinear interaction (pooled deviation) was significant. Based on overall yield performance, the Sarsabz variety produced the highest seed yield (4.37 T/ha) followed by Bakhtawar (4.24 T/ha) and Pasban-90 (3.93 T/ha). Regression coefficient values showed non significant differences to unity while standard deviation to regression showed significant differences to zero. These results indicated that the genotypes viz. Sarsabaz, Bakhtawar and Pasban-90 are better tolerant to saline environment as compared to others. The two genotypes, Marvi and 25219 had low regression values and can fit under stress environment. 相似文献
7.
冬小麦田咸水灌溉与土壤盐分调控试验 总被引：6，自引：0，他引：6
利用浅层咸水灌溉，可使浅层咸水分布区无效降水转化为有效水资源，缓解北方水资源紧缺的矛盾；通过王瞳试验场进行的咸水灌溉与土壤盐分调控试验表明，利用3g/L左右的微咸水连续灌溉5a，根层土壤溶液浓度未超过小麦的耐盐能力，且作物增产；多年盐分变化趋势为：1994－1997年1m深度内土壤总含盐量在一定范围内波动，总体变化不大，连续干旱的1997－1998年略呈上升趋势；麦秸覆盖和施有机肥能减少根层土壤盐分，对土壤盐分具有有利的调控作用，具有增产效果。 相似文献
8.
Abu El-Eyuoon Abu Zied Amin 《Arabian Journal of Geosciences》2018,11(23):759
Most arid and semi-arid soils, especially calcareous sandy soils, are widely distributed in the Middle East region; the deficiency in their content of many nutrients particularly phosphorus and organic matter limits crops production. This study aimed to assess the effects of adding biochar (B) with farmyard manure (FYM) and poultry manure (PM) on some soil properties, phosphorus (P) availability, and barley growth in calcareous sandy soil. The pot experiment includes the following treatments: Control, B, B?+?FYM (1:1), B?+?PM (1:1), B?+?FYM (2:1), B?+?PM (2:1), FYM?+?B (2:1), and PM?+?B (2:1). Biochar combined with FYM and PM enhanced the water holding capacity (WHC) and soil organic matter (SOM) content in calcareous sandy soil. Phosphorus availability was increased significantly by applying biochar mixed with farmyard manure and poultry manure at all treatments. Green biomass of barley improved because of adding biochar alone, poultry manure alone, and biochar co-applied with poultry manure at all mixing ratios. Biochar application caused significant increases in phosphorus use efficiency (PUE) by barley plants compared to all other treatments, except for the control. We recommend adding biochar either individually or mixed with poultry manure to improve the productivity of calcareous sandy soil. 相似文献
9.
Mats Söderström 《Environmental Geology》1992,20(2):85-92
Spatial distribution of the salinity in groundwater used for irrigation and irrigated soil was investigated on Gammouda Plain, an important agricultural area in central Tunisia. Samples from 188 wells and irrigated fields were obtained in November 1988. Groundwater salinity ranges from 2 to 30 dS/m, and 50 percent of the sampled wells have a salinity higher than 3.5 dS/m. In most cases the soil samples have a salinity higher than 4 dS/m. Maps of salinity and leaching were produced by a geostatistical interpolation method based on ordinary kriging. In a great part of the plain, the estimated salinity levels indicate that there is a considerable risk for reduced yield potential for several of the most important crops grown. A rough estimation of the leaching fraction was computed from the soil and water salinity. Computer-based models of salinity ought to facilitate the general planning of irrigation management and crop selection. 相似文献
10.
In order to study the distribution and evolution features of saline soil, the correlations between the groundwater depth, salinity and salinization of soil are examined through analyzing the hydrometeorological data and distribution maps of saline soil, groundwater depth and salinity in 1957 and 2005. The results show that the area of salinization has generally decreased. The area of salinization decreases with the increasing groundwater depth, and the dynamic evolution characteristics appeared between the groundwater depth and area of salinization. The area of heavy salinization is greatest when the groundwater salinity is > 5 g/L, the area of moderate salinization is greatest when the groundwater salinity is between 2-5 g/L, the area of light salinization is greatest when the groundwater salinity is 1-2 g/L and the area of non-salinization is greatest when the groundwater salinity is <1 g/L. The area of heavy salinization was characterized with groundwater depth <2.5 m and salinity >1.8 g/L. The area of non-salinization was characterized with groundwater depth >4.0 m and salinity 0.2-1.5 g/L. 相似文献
11.
微咸水在西北干旱区广泛分布, 越来越多地被运用于灌溉棉花(Gossypium hirsutum L.)等作物.微咸水中NaCl和微量元素含量比淡水高, 有关NaCl和微量元素各自对棉花生长的影响已有大量研究, 而他们对棉花生长的相互作用研究比较缺乏.选取对棉花生长作用敏感的NaCl和微量元素Zn, 开展不同NaCl和Zn浓度灌溉水盆栽试验.结果表明, 缺Zn环境下, 在灌溉水电导率为2.90~3.95 dS/m的范围内, 随着电导率增大, NaCl促进棉花根和地上部生长及皮棉产量增加.富Zn环境下, 灌溉水电导率大于5.04 dS/m时, 随着电导率增大皮棉产量明显下降.在灌溉水中Zn浓度为0.192 0~3.068 0 μmol/L的范围内, Zn浓度越大棉花营养生长越快; 大于0.767 6 μmol/L时, 随着Zn浓度增大皮棉产量下降.灌溉水中NaCl和Zn对棉花生长和产量的影响作用, 表现为相互拮抗作用关系.棉花叶的Ca、K、Mg、B和Fe含量以及铃的Cu和Zn含量高于其他组织, Na和Mn不易迁移, 易富集在棉花根部.Zn在盐胁迫条件下影响棉花对营养元素的吸收, 使棉花体内相关营养元素含量发生变化, 进而影响棉花生长及产量. 相似文献
12.
Fei Zhang Tashpolat Tiyip Jianli Ding Hsiangte Kung Verner C. Johnson Mamat Sawut Nigara Tashpolat Dongwei Gui 《Environmental Earth Sciences》2013,69(8):2743-2761
There has been growing interest in the use of reflectance spectroscopy as a rapid and inexpensive tool for soil characterization. In this study, 53 soil samples were collected from the oasis in the Weigan and Kuqa River delta along the middle reaches of Tarim River to investigate the level of soil chemical components in relation to soil spectral. An approach combining spectral technology and multi-variant statistical analysis was used to determine the reflectance spectral features of saline soil. The spectral data was first pretreated to remove noises and absorption bands from water, which eliminated influence from instrument errors and other external background factors. Several spectral absorption features were calculated for several saline soil samples to confirm that soil at the same salinity level had similar absorption spectral properties. Secondly, a correlation relationship between reflectance spectra and salinity factors was estimated by bivariate correlation method. Fourteen salinity factors including eight major ions and soil electrical conductivity (EC), soil salt content (SSC), pH, and total dissolved solid (TDS) in the saline soil were evaluated. Datasets of the salinity factors that correlated significantly with field data measurements of reflectance rate and the corresponding spectrum data were used to construct quantitative regression models. According to the multiple linear regression analysis, SSC, SO4 2?, TDS, and EC had a correlation coefficient at 0.746, 0.908, 0.798, and 0.933 with the raw spectral data, respectively, which confirmed strong correlation between salinity factors and soil reflectance spectrum. Findings from this study will have significant impact on characterization of spectral features of saline soil in oasis in arid land. 相似文献
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为了研究不同草本植物间作对空心菜生长状况及对Pb的吸收、转运效果,采用盆栽试验,研究了空心菜在Pb污染土壤中单作及与10种草本植物(高丹草、苏丹草、狼尾草、黑麦草、苦荬菜、菊苣、籽粒苋、三叶草、紫花苜蓿、紫云英)间作对Pb吸收、积累的影响。结果表明：空心菜与黑麦草、苦荬菜、菊苣、籽粒苋、三叶草、紫花苜蓿以及紫云英间作后的茎叶生物量较空心菜单作增加显著(P<0.05),增加了15.79%~84.75%。不同间作方式下的空心菜茎叶Pb含量为7.11~15.36 mg/kg,茎叶Pb富集系数(BCF)为0.024~0.051,根茎叶Pb转运系数(TF)为0.240~0.470。与高丹草、苏丹草、苦荬菜、菊苣以及籽粒苋间作后,空心菜茎叶Pb含量较单作(对照)降低了24.39%~41.46%,茎叶Pb积累量较单作降低了65.36%~75.06%;此外,与上述5种植物间作后空心菜的根际土壤有效态Pb含量降低了4.47%~9.09%,根际土壤pH值则增加了0.32%~2.74%。10种间作植物茎叶Pb含量大小为菊苣>黑麦草>苦荬菜>高丹草>苏丹草>紫云英>紫花苜蓿>狼尾草>三叶草>籽粒苋。不同间作方式下每盆植株Pb总积累量为0.560~2.108 mg/盆,10种间作处理是空心菜单作处理的1.73~3.76倍。研究结果表明,高丹草、苏丹草、苦荬菜、菊苣和籽粒苋与空心菜间作有效降低了空心菜对Pb的吸收积累,同时提高了整个体系对土壤中Pb的总积累量,在间作修复中是较为理想的组合模式。 相似文献
14.
Muhammad Zia ur Rehman Muhammad Rizwan Shafaqat Ali Muhammad Irfan Sohail Amjad Hussain Muhammad Farooq Qayyum Hinnan Khalid Muhammad Zeeshan Naveeda Majid 《Arabian Journal of Geosciences》2018,11(21):685
Biochar is considered a promising amendment for the reduction of metal concentration in plants; however, the effects of biochar in terms of dose and feedstock on metal uptake by plants remain widely unclear. In the current study, three individual biochars were prepared at 450 °C from different feedstocks (wheat straw, sukh chain (Pongamia pinnata), and cotton sticks). The main aim was to evaluate their ability to remediate cadmium (Cd)-spiked soil in terms of growth response and Cd uptake by wheat (Triticum aestivum) tissues. Biochars were separately applied at 0, 1, and 2% (w/w) in Cd-spiked soil and wheat was grown until maturity in pots and then morphological and physiological parameters and Cd concentrations in grains, roots, and shoots were determined. The post-harvest soil was analyzed for extractable Cd concentrations. Plants grown in Cd-spiked soil treated with biochars had higher seed germination, lengths of roots, shoots, and spikes, grains per spike and leaf relative water contents, chlorophyll contents, and dry weight of roots, shoots, and grains as compared to the untreated control. Biochar treatments significantly decreased the Cd concentrations in shoots, roots, and grains as well as total Cd uptake by grains. Soil extractable Cd concentrations were significantly decreased with biochar treatments. The application of 2.0% wheat straw biochar was the most efficient treatment in increasing grain yield and decreasing Cd in grains as well as soil extractable Cd than the other two biochars and doses applied. 相似文献
15.
《International Geology Review》2012,54(6):495-500
The authors consider those geobotanical indicators which differentiate ground-water resources of varying salinity and depth. The territory under study is the Chernyye Zemli region; the aim is primarily to locate potable water for cattle. The most reliable fresh-water indicators were found to be certain sweet clover associations. The lower the mineral content of the water and the closer it is to the surface, the more luxuriant this plant species. A specie of sagebrush is another reliable sign. Moderately saline waters were marked by associations of wormwood with some dwarfed sagebrush and cypresses or with vetch, Gypsophila and wild rye. It is noted that the latter are indicators of moderately saline water, when found in association with wormwood. Saline waters (dry residue over 12 g per L) were characterized by various sagebrushes, particularly Artemisia incana, and if this species is present in sweet clover associations even in small numbers, a higher degree of salinity is present. Field checking verified 78 percent of interpretations from aerial photography. --A. Eustus. 相似文献
16.
Recent environmental changes in Laguna Mar Chiquita (central Argentina): a sedimentary model for a highly variable saline lake 总被引：1，自引：0，他引：1
Abstract Laguna Mar Chiquita, a highly variable closed saline lake located in the Pampean plains of central Argentina, is presently the largest saline lake in South America (≈ 6000 km2). Recent variations in its hydrological budget have produced dry and wet intervals that resulted in distinctive lake level fluctuations. Results of a multiproxy study of a set of sedimentary cores indicate that the system has clearly recorded these hydrological variations from the end of the Little Ice Age (≈ ad 1770) to the present. Sedimentological and geochemical data combined with a robust chronology based on 210Pb profiles and historical data provide the framework for a sedimentary model of a lacustrine basin with highly variable water depth and salinity. Lake level drops and concurrent increases in salinity promoted the development of gypsum–calcite–halite layers and a marked decrease in primary productivity. The deposits of these dry stages are evaporite‐bearing sediments with a low organic matter content. Conversely, highstands are recorded as diatomaceous organic matter‐rich muds. Average bulk sediment accumulation rose from 0·22 g cm?2 year?1 in lowstands to 0·32 g cm?2 year?1 during highstands. These results show that Laguna Mar Chiquita is a good sensor of high‐ and low‐frequency changes in the recent hydrological budget and, therefore, document climatic changes at middle latitudes in south‐eastern South America. Dry conditions were mostly dominant until the last quarter of the twentieth century, when a humid interval without precedent during the last 240 years of the lake's recorded history started. Thus, it is an ideal system to model sedimentary and geochemical response to environmental changes in a saline lacustrine basin. 相似文献
17.
通过野外定位观测和室内分析,探讨了冻融季节的微域尺度(32 m长的横剖面)苏打盐渍土的水分和盐分的变化规律.结果表明:冻结期大量地下水迁移并储存在盐化草甸土的冻层中,同时地下水位埋深迅速从1.2 m下降到2.5 m以下;苏打盐化草甸土冻结层的含水率明显增加,其中30~40 cm土层的含水率变化最明显(从冻结前的20%增加到50%).苏打碱土冻层的含水率增量不明显,但盐分显著增加,其中白盖苏打碱土表层的盐分增量幅度达80%.盐分变化主要表现为苏打盐渍土表层HCO3-、CO32-、SO42-以及Na+的增加,大量盐分表聚使消融期土壤的盐渍化程度不断加重. 相似文献
18.
为了全面地揭示硫酸盐渍土击实性能的变化原因和规律,对不同条件下配制的硫酸盐渍土进行了一系列的轻型击实试验。试验研究表明,含盐量对硫酸盐渍土最大干密度和最优含水率的影响规律并不是单一不变的,它取决于土中硫酸钠的3种状态（硫酸钠溶液、无水硫酸钠和十水硫酸钠）及3种状态间的相对含量。硫酸盐渍土的最大干密度和最优含水率与土中不同状态硫酸钠相对含量间的关系曲线具有反相关性。闷料时间和初始含水率对硫酸盐渍土击实性能的影响与含盐量有关,当含盐量较低（如1.5%）时,其影响甚小;当含盐量较高（如5.0%）时,其影响显著。硫酸盐渍土在由湿到干的过程中会出现“假干现象”。该试验结果对工程中硫酸盐渍土的击实性能和压实度的合理评价都具有重要的参考价值。 相似文献
19.
依据引黄水在北大港水库蓄存期水质咸化的事实以及传质理论,定性地分析了引黄水水质咸化的主要原因,包括盐碱土传质作用、蒸发浓缩作用以及风的扰动加速传质作用等.在北大港水库旁修建了一个模拟试验水池,进行了现场模拟试验研究.依据水量平衡和氯离子总量平衡的原理,分别定量地计算了传质作用和蒸发浓缩作用对水质咸化影响的比重.结果表明,在模拟水池蓄水后的30 d内,传质作用对水质咸化影响的比重有随时间增加而增长的趋势;30 d后,传质作用对水质咸化影响的比重稳定在80%,蒸发浓缩作用对水质咸化影响的比重稳定在20%,说明导致水质咸化的最主要因素是盐碱土传质作用. 相似文献
20.
M. L. Dotaniya S. Rajendiran M. Vassanda Coumar V. D. Meena J. K. Saha S. Kundu A. Kumar A. K. Patra 《International Journal of Environmental Science and Technology》2018,15(2):441-448
A pot culture experiment was conducted to study impact and interaction of multi-metals on growth, yield and metals uptake by spinach (variety All Green). Three levels of each chromium (0, 50 and 100 mg/kg), cadmium (0, 1 and 2 mg/kg) and zinc (0, 10 and 20 mg/kg) in combinations (total treatments 3 × 3 × 3 = 27) were applied in a Vertisol (5 kg). The results showed that increasing the concentration of chromium, cadmium and zinc in soil enhanced the respective metal concentrations in spinach root and shoot. When cadmium at 2 mg/kg along with chromium at 100 mg/kg soil was applied, chromium concentration and uptake were decreased in root and shoot. Meanwhile, zinc application had no significant effect on chromium uptake and concentration in spinach biomass. From the results, it was concluded that cadmium at higher dose had an antagonistic effect over chromium. On the other hand, in chromium, cadmium and zinc combinations particularly at their higher levels, a competition among each other was found. Therefore, the findings could be used as guidelines for controlling and management of heavy metals pollution in farmland. 相似文献