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1.
Nahid Rezaie Ali Reza Sepaskhah 《Communications in Soil Science and Plant Analysis》2019,50(5):611-626
Greenhouse experiment was conducted to investigate the effect of different levels of irrigation water salinity (0.5, 2.5, 5 and 7.5 dS m?1) and wheat straw biochar (0%, 1.25%, 2.5%, and 3.75% w/w) on growth and yield of faba been using complete randomized design with three replications. Stomatal conductance (green canopy temperature) of faba bean increased (decreased) by application of biochar at each salinity level. The results showed increasing salinity to 2.5 dS m?1 at zero biochar application increased the seed yield through osmotic adjustment, while by declining the osmotic potential, the nutritional values of biochar caused the seed yield to increase by increasing salinity to 5 dS m?1. The root length density and root dry weight density in 0–8 cm soil layer declined under application of 3.75% w/w biochar in all salinity levels in comparison with that obtained in 2.5% w/w biochar, due to higher saline condition of the soil as result of higher biochar application. The results showed that addition of 2.5% w/w biochar can significantly mitigate salinity stress due to its high salt sorption capacity and by increasing potassium/sodium ratio in the soil. In general, since 2.5 % w/w biochar and salinity of 5 dS m?1 increased dry seed yield and irrigation water productivity compared with that obtained in control (B0S0.5), these levels are recommended to improve faba bean growth and yield; however, these levels have to be evaluated under field conditions. 相似文献
2.
为探明干旱地区盐碱地膜下滴灌不同灌水下限施用生物炭对玉米产量和水肥利用效率的响应差异及相互影响关系,提出较优的灌溉制度和生物炭用量。连续2年在河套灌区盐渍化农田玉米生长阶段进行小区控制试验,设计3个灌水下限[土壤基质势为-15(W15),-25(W25),-35(W35)kPa,灌水定额为22.5 mm]和3个生物炭用量水平[0(B0),15(B15),30(B30)t/hm2],2因素完全随机试验设计,共9个处理。测定并分析玉米全生育期0—15 cm土壤理化性状、作物生长特征和水氮利用效率。结果表明：不同灌水下限施用生物炭整体提高玉米全生育期土壤含水率、有机质和碱解氮含量,同一灌溉水平下生物炭用量越高,各指标提升的幅度越大。施用生物炭提高玉米地上部干物质积累量和产量,灌溉水利用效率和氮肥偏生产力显著提高,且生物炭施用当年的效果普遍优于翌年。相较于不施用生物炭的对照,W15、W25、W35条件下,B15使玉米产量平均增加12.8%,10.3%,14.2%,灌溉水利用效率提高14.2%,10.4%,12.9%,氮肥偏生产力提升12.8%,10.4%,14.0%,其节... 相似文献
3.
西辽河平原覆膜和浅埋对滴灌玉米生长的影响 总被引：1，自引：0，他引：1
为对比研究覆膜和浅埋对滴灌玉米生长的影响,以西辽河平原为研究区,设置膜下滴灌与浅埋滴灌2种灌溉方式和高、中、低3种灌溉水平,对滴灌玉米生长指标、根系分布、耗水量及产量等进行分析,寻求适宜试验区玉米高效节水灌溉模式。结果表明:(1)平均叶面积指数膜下滴灌较浅埋滴灌处理高13%～20%。膜下滴灌根系在30 cm土层内分布均匀,浅埋滴灌根系分布较膜下滴灌深10 cm。(2)膜下滴灌总耗水量较浅埋滴灌低9%,节水效果明显。(3)平水偏枯年膜下滴灌处理产量高于浅埋滴灌7%～15%,平水偏丰年膜下滴灌处理的产量低于浅埋滴灌处理6%～19%(p0.05)。(4)中水处理产量高,水分生产率最大,为最佳灌水处理。(5)对不同研究区通过多年平均降雨量和当年降雨预报推算生育期降雨量,对于268.32 mm的地方推荐使用膜下滴灌更佳,灌溉定额为186.1 mm,灌水7次。降雨量268.32 mm的地方推荐使用浅埋滴灌更佳,灌溉定额为228.0 mm,灌水8次。研究结果可为试验区及类似地区玉米高效灌溉生产提供理论依据。 相似文献
4.
加入不同量生物质炭盐渍化土壤盐分淋洗的差异与特征 总被引：5，自引：1，他引：4
生物质炭作为土壤调理剂,能够显著地改良培肥土壤,但对盐渍化土壤盐分淋洗的影响缺乏研究和了解。本研究采用土柱模拟试验,将蘑菇棒生物质炭按照不同的质量比(0%、2%、5%、10%),添加到内蒙古河套地区硫酸盐盐渍化土壤0～20 cm的土层中,并进行淋洗,测定淋出液和土壤盐分及主要盐分离子含量,以期了解生物质炭对土壤盐分和主要盐分离子洗脱的影响。结果表明:加入生物质炭的土柱,淋洗液出现的时间提前了5～36 d,电导率降低至5 mS cm-1缩短了41～100 d;生物质炭加入量越大,淋洗液出现的时间越早,电导率降低至5 mS cm-1所需的时间也越少。其中,生物质炭用量2%的处理,淋洗结束表层脱盐效果较好,含盐量与对照相比降低了34.25%。显然,向盐渍化土壤加入生物质炭,不仅能够缩短盐分洗脱时间,而且提高洗盐效率,但对盐分离子洗脱先后顺序及其速率,并没有表现出明显的影响。 相似文献
5.
ABSTRACT A two-year consecutive experiment was conducted at agriculture Research Institute Mingora Swat, Pakistan during Rabi 2016–17 and 2017–18 to study the residual effect of carbon sources on water use efficiency and subsequent wheat productivity. Carbon sources (peach leaf and rotten fruits on dry basis, compost of peach residues and biochar of these residues), Three P rates (P1 = 50, P2 = 75, and P3 = 100 kg P ha?1) with two irrigation levels (225 and 175 mm) along with traditional planting with no irrigation, were used in the experiment. No carbon sources or phosphorus was applied to the wheat crop at any stage. The results clearly indicated that CS such as biochar with improved irrigation system of 225 mm could enhance the soil water availability in 0–100 cm during the key growth stages, as well as WUE and rainfall use efficiency were improved by 34% and 51% as compared with no irrigation, respectively. Maximum yield components were produced by compost while biological yield was increased with biochar amendments. It is concluded that irrigation volume of 225 mm produced higher grain yield when wheat was sown after the preceding crop treated with biochar and 75 kg P ha?1. It is concluded that biochar with 225 mm irrigation level is a suitable treatment for efficient consumption of local rainfall and increase subsequent wheat productivity under the northern climatic scenario of Pakistan because it improves the Evapo Transpiration (WUE), Radiation Use Efficiency (RUE) and reduces ET levels, thereby enhancing the grain yield, net pro?t, and food security. 相似文献
6.
生物质炭和果胶对再生水灌溉下玉米生长及养分、重金属迁移的影响 总被引：1，自引：0，他引：1
利用根箱试验方法比较了生物质炭和果胶对再生水灌溉下土壤—植物系统养分和重金属迁移特征的影响及差异性。结果表明,再生水灌溉不利于植物的生长,果胶和生物质炭两个处理相比,虽然植株生长无显著差异,但果胶处理植株的生长状况优于生物质炭处理;再生水灌溉时,果胶处理地上部生物量比对照增加了59.32%。与蒸馏水灌溉相比,再生水灌溉增加了根际土壤pH;灌溉水源相同时,果胶处理根际土壤pH略低于生物质炭处理。生物质炭和果胶都增加了土壤养分的含量,果胶对土壤碱解氮、有效磷和有机质的增加效果优于生物质炭,生物质炭对土壤有效钾的增加幅度大于果胶。生物质炭增加了植株的养分含量,果胶提高了养分的转运能力。生物质炭降低了土壤有效态Fe、Mn、Cu、Ni的含量,果胶增加了土壤有效态Fe、Mn、Cu、Pb、Ni的含量。果胶处理植株根系重金属含量普遍高于生物质炭处理,如蒸馏水灌溉下果胶处理根系Fe、Mn、Cu、Zn、Pb、Cd、Ni含量分别比生物质炭处理增加了165.29%,113.01%,21.16%,92.74%,14.61%,26.86%和53.43%,但Cu、Zn、Pb、Cd、Ni等元素在果胶处理的转运系数最低。该研究可为再生水灌溉下生物质炭和果胶在北方碱性土壤的农业安全利用提供理论依据。 相似文献
7.
Saeed Sanaei Ardakani Mehdi Shorafa Abdolmajid Liaghat Mohsen Farahbakhsh Farhad Dehghani 《Communications in Soil Science and Plant Analysis》2019,50(3):237-253
Disruption in the nitrogen (N) cycle balance has a negative impact on the overall trend of sustainable development, and using soil amendments is necessary to reduce these hazards. This study was carried out as a factorial experiment in a completely randomized design. The treatments consisted of three levels of amendments (0, 7.5 g/kg of pistachio residues, and 7.5 g/kg of biochar) and four levels of irrigation water salinity including 0.5 (urban water), 5.5, 8, and 10.5 dS/m and in three replications. Two pistachio seedlings were transferred to all columns and then in three steps, and in each step, 25 mg N/kg of potassium nitrate was added. The results indicated that pistachio residuals and its biochar increased nitrate outflow from effluent by 9% and 52%, respectively. The effects of amendment treatment and irrigation water salinity on all three characteristics of output nitrate, soil nitrate, and absorbed plant nitrate were significant at 1% level. 相似文献
8.
A. R. A. USMAN M. I. AL-WABEL Y. S. OK A. AL-HARBI M. WAHB-ALLAH A. H. EL-NAGGAR M. AHMAD A. Al-FARAJ A. AL-OMRAN 《土壤圈》2016,26(1):27-38
Thermally modified organic materials commonly known as biochar have gained popularity of being used as a soil amendment.Little information, however, is available on the role of biochar in alleviating the negative impacts of saline water on soil productivity and plant growth. This study, therefore, was conducted to investigate the effects of Conocarpus biochar(BC) and organic farm residues(FR) at different application rates of 0.0%(control), 4.0% and 8.0%(weight/weight) on yield and quality of tomatoes grown on a sandy soil under drip irrigation with saline or non-saline water. The availability of P, K, Fe, Mn, Zn and Cu to plants was also investigated. The results demonstrated clearly that addition of BC or FR increased the vegetative growth, yield and quality parameters in all irrigation treatments. It was found that salt stress adversely affected soil productivity, as indicated by the lower vegetative growth and yield components of tomato plants. However, this suppressing effect on the vegetative growth and yield tended to decline with application of FR or BC, especially at the high application rate and in the presence of biochar. Under saline irrigation system, for instance, the total tomato yield increased over the control by 14.0%–43.3% with BC and by 3.9%–35.6% with FR. These could be attributed to enhancement effects of FR or BC on soil properties, as indicated by increases in soil organic matter content and nutrient availability. Therefore, biochar may be effectively used as a soil amendment for enhancing the productivity of salt-affected sandy soils under arid conditions. 相似文献
9.
咸水畦灌农田土壤水热盐动态及油葵生长的试验与模拟 总被引：1，自引：1，他引：0
为探究中国西北旱区咸水畦灌条件下农田土壤水热盐动态及其对作物生长的影响,采用大田试验和WASH-C模型(Layered Soil Water-Solute-Heat Transport and Crop Growth Model,土壤水热盐迁移和作物生长耦合的模拟模型)模拟相结合的方法,分析油葵全生育期内不同灌水量和矿化度处理下土壤剖面水盐分布特征、温度变化及油葵生长规律。试验设置包括2个灌水量水平(分别为油葵畦灌需水量的100%、50%)和3种畦灌水矿化度(分别为0.7、4.0、8.0 g/L)。结果表明,土壤剖面的水、盐、热分布在根区(0～40 cm)的变动幅度要大于深层(40～100 cm),灌水量越多,水分、盐分变幅越大。随着灌水次数的增加,土壤剖面在0.7 g/L矿化度下出现脱盐现象,4.0、8.0 g/L矿化度下出现积盐现象,并且灌水量越大,相应的脱、积盐率越高。试验前期各层地温变化幅度较后期大,温度变化幅度随土壤深度增加而减小。0.7g/L、100%油葵需水量下的作物LAI和产量最大,8g/L、50%油葵需水量下最小,两处理的LAI分别为8.41、3.80 cm~2/cm~2,产量分别为5.49、3.08t/hm~2,差异显著(P0.05)。模拟结果表明,WASH-C能够较好地模拟各时期土壤中根区、深层含水率的分布特征,所有模拟结果的R2不低于0.53。在咸水矿化度小于等于3g/L的情景模拟下,作物根区不会产生明显的积盐现象。合理的咸水畦灌制度有利于充分利用咸水资源并提高油葵的水分利用效率和产量。 相似文献
10.
咸淡水轮灌对棉花产量和土壤溶质迁移的影响 总被引：3，自引：2，他引：3
为探讨不同咸淡水膜下滴灌方式对棉花根系、产量和土壤剖面溶质迁移的影响,于2012–2013年在巴州灌溉试验站开展大田试验,共设置全生育期微咸水、淡水和咸淡水轮灌(蕾期—花铃前期淡水、其余生育期微咸水)3个处理。对比不同咸淡水处理下,棉花根系发育、地上部生长和产量的差异,分析0~100 cm土壤中铜、铁、锰、钙、钾、钠6种溶质垂向分布与变化特点。结果表明:2012年,微咸水灌溉条件下,钠离子未发生表聚,40 cm以上土壤微量元素含量显著增高(P0.05),棉花总根长密度、最大根长密度呈咸水处理轮灌处理淡水处理,咸水和轮灌处理下,单株棉花地上部干物质、单位面积铃数和籽棉产量显著高于淡水处理,分别达32%、20%和22%。2012–2013年,咸水处理下棉花总根长密度骤减,导致该处理下单株棉花地上部干物质、单位面积铃数和籽棉产量显著降低(P0.05)。在土壤盐害离子增加,微量元素减少的情况下,采用蕾期至花铃前期淡水灌溉、其余生育期微咸水灌溉的方式,钠离子未发生表聚,2013年棉花总根长密度高于咸水处理达24%,地上部干物质、单位面积铃数和籽棉产量较咸水处理高出13%~24%。咸淡水轮灌一定程度上促进了棉花根系生长,缓解盐害离子对棉花造成的生长胁迫。另外,不同咸淡水灌溉处理下,土壤溶质迁移规律不同:2012–2013年,土壤中铜、铁、锰平均质量分数降低约40%,0~10 cm的表聚系数由0.14~0.17增长至超过0.20,3种处理下铜、铁、锰都表现出强烈的表聚性;钙、钾、钠平均质量分数增加33%~45%,3种处理下钙、钾未表现出明显的表聚性,而微咸水处理下钠由不表聚转变为显著表聚。该成果可为干旱地区合理利用微咸水,实现棉花优质稳产提供参考。 相似文献
11.
Edris Gavili Farzad Moradi Choghamarani 《Archives of Agronomy and Soil Science》2018,64(12):1714-1727
Drought and low amounts of organic matter are two main constraints in arid and semiarid regions and their adverse effects on soils and plants can be alleviated by biochar (B). Therefore, the influence of 0 (0B), 1.25 (1.25B), 2.5 (2.5B) and 5% (5B) cattle-manure biochar on the growth and physiological traits of spinach and physical characteristics of postharvest soil under field capacity (FC), 0.7FC and 0.55FC conditions was evaluated. Drought decreased stomatal conductance (SC), water use efficiency (WUE), shoot dry matter yield (SDMY), soil water repellency (WR) and saturated hydraulic conductivity (Ks) by 13–45%, 3–17%, 27–51%, 48–60% and 26–36%, respectively. Whereas, all B treatments increased SC, Ks and total porosity by 11–63%, 82–221% and 2–12%, respectively. Application of 1.25B increased SDMY and WUE, whereas higher B levels were ineffective, i.e. 2.5B did not significantly affect the measured parameters and 5B reduced them. At all B levels, drought reduced SDMY. However, the lowest decrease in SDMY was observed by 1.25B. Despite their positive influence on soil’s physical quality, high B levels induced excessive salinity. Therefore, a low B level (1.25B) may be recommended since it provides positive impacts on the plant’s growth and yield while mitigating the adverse effects of drought. 相似文献
12.
L. Wang C. R. Butterly Y. Wang H. M. S. K. Herath Y. G. Xi X. J. Xiao 《Soil Use and Management》2014,30(1):119-128
Strongly acidic soil (e.g. pH < 5.0) is detrimental to tea productivity and quality. Wheat, rice and peanut biochar produced at low temperature (max 300 °C) and differing in alkalinity content were incorporated into Xuan‐cheng (Ultisol; initial pHsoil/water = 1/2.5 4.12) and Ying‐tan soil (Ultisol; initial pH soil/water = 1/2.5 4.75) at 10 and 20 g/kg (w/w) to quantify their liming effect and evaluate their effectiveness for acidity amelioration of tea garden soils. After a 65‐day incubation at 25 °C, biochar application significantly (P < 0.05) increased soil pH and exchangeable cations and reduced Al saturation of both tea soils. Association of H+ ions with biochar and decarboxylation processes was likely to be the main factor neutralizing soil acidity. Further, biochar application reduced acidity production from the N cycle. Significant (P < 0.05) increases in exchangeable cations and reductions in exchangeable acidity and Al saturation were observed as the rate of biochar increased, but there were no further effects on soil pH. The lack of change in soil pH at the higher biochar rate may be due to the displacement of exchangeable acidity and the high buffering capacity of biochar, thereby retarding a further liming effect. Hence, a significant linear correlation between reduced exchangeable acidity and alkalinity balance was found in biochar‐amended soils (P < 0.05). Low‐temperature biochar of crop residues is suggested as a potential amendment to ameliorate acidic tea garden soils. 相似文献
13.
E. W. Bruun C. T. Petersen E. Hansen J. K. Holm H. Hauggaard‐Nielsen 《Soil Use and Management》2014,30(1):109-118
Crop yields and yield potentials on Danish coarse sandy soils are strongly limited due to restricted root growth and poor water and nutrient retention. We investigated if biochar amendment to subsoil can improve root development in barley and significantly increase soil water retention. Spring barley (Hordeum vulgare cv. Anakin) was grown in soil columns (diameter: 30 cm) prepared with 25 cm topsoil, 75 cm biochar‐amended subsoil, and 30 cm un‐amended subsoil lowermost placed on an impervious surface. Low‐temperature gasification straw‐biochar (at 0, 0.50, 1.0, 2.0, and 4.0 wt%) and slow pyrolysis hardwood‐biochar (at 2 wt%) were investigated. One wt% can be scaled up to 102 Mg/ha of char. After full irrigation and drainage, the in‐situ moisture content at 30‐80 cm depth increased linearly (R2 = 0.99) with straw‐biochar content at a rate corresponding to 0.029 m3/m3/%. The lab determined wilting point also increased linearly with char content (R2 = 0.99) but at a much lower rate (0.003 m3/m3/%). Biochar at concentrations up to 2% significantly increased the density of roots in the 40–80 cm depth interval. Addition of 1% straw‐biochar had the most positive effect on root penetration resulting in the highest average root density (54% coverage compared to 33% without biochar). This treatment also resulted in the greatest spring barley grain yield increase (22%). Improving the quality of sandy subsoils has global potentials, and incorporation of the right amount of correctly treated residues from bioenergy technologies such as straw‐biochar is a promising option. 相似文献
14.
北疆膜下滴灌棉花产量及水分生产率对灌水量响应的模拟 总被引：5，自引：6，他引：5
膜下滴灌技术是一种节水高产的灌溉技术,在新疆棉花种植中得到了广泛的应用。灌溉是影响新疆棉花产量的重要因素。为研究棉花产量和水分生产率对灌水量的响应,该文首先采用2010年和2011年新疆棉花膜下滴灌田间试验数据验证二维土壤水与作物生长耦合模型模拟棉花产量和耗水量可靠性。结果表明,二维土壤水与作物生长耦合模型能够可靠地模拟土壤含水率、叶面积指数、地上部分干物质量、籽棉产量和耗水量。土壤含水率模拟值与实测值的标准均方根误差(normalized root mean square error,n RMSE)为4.6%~23.4%,一致性指数为0.677~0.974;叶面积指数和地上部分干物质量n RMSE分别为6.3%~15.7%和7.2%~14.1%;籽棉产量和耗水量的模拟值与实测值之间相对误差分别仅为1.1%~6.7%和0.3%~9.2%。利用率定和验证后的模型参数进一步模拟10种灌水量情景下的棉花籽棉产量和水分生产率,结果表明籽棉产量随着灌水量的增加而增加,二者呈抛物线关系,而水分生产率则随着灌水量的增加而减小。综合考虑产量和水分生产率,北疆地区膜下滴灌棉花优化灌水量为280~307 mm。该研究可为北疆地区棉花灌水实践提供科学依据。 相似文献
15.
Leila Romdhane Yasser Mahmoud Awad Leila Radhouane Cristian Dal Cortivo Giuseppe Barion Anna Panozzo 《Archives of Agronomy and Soil Science》2019,65(6):846-866
This study investigated the effects of wood-derived biochar (BC) applied at 1% to a C-poor silty-loam soil in the drought-tolerant (D24) and in the drought-sensitive (P1921) Pioneer Hi-Bred maize hybrids in pot and field trials (NE Italy). D24 had better growth than P1921 under rain-fed conditions without irrigation and soil amendment. The addition of biochar increased root growth in D24 (+38% root area) and decreases it in P1921 (?9%) at the silking stage, while the fraction of finer roots (<250 µm diam.) was reduced in D24 and increased in P1921. This led both hybrids to maintain the maximum transpiration at a lower fraction of transpirable soil water (from 82% to 45% in D24, and from 46% to 22% in P1921). There were no significant variations in plant nutrient contents, productivity and in the protein and starch contents of the grains, whereas the lipid content was reduced by biochar, particularly in P1921 (2.6% vs. 3% DW, ?13%).We conclude that biochar can be profitably used to enhance drought tolerance in maize, possibly due to improvements in the physicochemical characteristics and the water content of treated soils, although maximum benefits are expected in drought-tolerant hybrids through increased root elongation and transpiration. 相似文献
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Biochar has the potential to decrease salinity and nutrient loss of saline soil. We investigated the effects of biochar amendment (0–10 g kg−1) on salinity of saline soil (2.8‰ salt) in NaCl leaching and nutrient retention by conducting column leaching experiments. The biochar was produced in situ from Salix fragilis L. via a fire-water coupled process. The soil columns irrigated with 15 cm of water showed that biochar amendment (4 g kg−1) decreased the concentration Na+ by 25.55% in the first irrigation and to 60.30% for the second irrigation in sandy loam layer over the corresponding control (CK). Meanwhile, the sodium adsorption ratio (SAR) of soil after the first and second irrigation was 1.62 and 0.54, respectively, which were 15.2% and 49.5% lower than CK. The marked increase in saturated hydraulic conductivity (Ks) from 0.15 × 10–5 cm s−1 for CK to 0.39 × 10–5 cm s−1, following 4 g kg−1 of biochar addition, was conducive to salt leaching. Besides, biochar use (4 g kg−1) increased NH4+-N and Olsen-P by 63.63% and 62.50% over the CK, but accelerated NO3–-N leaching. Since 15 cm hydrostatic pressure would result in salt accumulation of root zone, we would recommend using 4 g kg−1 of biochar, 30 cm of water to ease the problem of salt leaching from the surface horizon to the subsoil. This study would provide a guidance to remediate the saline soil in the Yellow River Delta by judicious application of biochar and irrigation. 相似文献
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稻壳炭对红壤理化特性及芥菜生长的影响 总被引：2，自引：0，他引：2
本文探讨了不同热解温度制备的稻壳炭的基本性质,并通过盆栽试验研究了500℃热解稻壳炭添加量对南方红壤理化性质和芥菜产量的影响。结果表明:稻壳炭添加量3%、5%和10%三个处理显著改善了红壤的理化性质,土壤体积质量较对照处理依次降低0.11、0.28和0.42 g/cm~3,p H由4.5分别增加到7.5、7.8、8.4,CEC依次增加52.16%、187.02%和214.35%,土壤有机质、速效磷和速效钾显著增加,但稻壳炭添加量10%处理的土壤碱解氮含量降低。稻壳炭对芥菜的养分含量、产量等指标影响较为显著,随着施炭量的增加,芥菜的生物量增加,叶片全氮从1.63 g/kg增加到2.44 g/kg,全磷从2.32 g/kg增加到3.09 g/kg,全钾从47.1 g/kg增加到56.7 g/kg,产量由108.37 g/盆增加到608.7 g/盆。总之,添加5%的500℃热解稻壳炭有效改善了酸度较强的红壤的理化性质,促进了芥菜的生长和增收以及对氮磷钾养分的吸收和储存。在红壤改良上,稻壳炭的最佳添加比例为5%。 相似文献
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为对城市绿地草坪草进行更合理的种植灌溉,采用小区微灌试验,对剪股颖、马蹄金、早熟禾和白三叶四种具有代表性的绿地草坪草的需水规律进行研究。试验结果表明:（1）供试草坪草根系在土层中的分布呈“伞”形结构,83%～94.4%的根系聚集在0—10 cm的土层中,不耐干旱,需适时补充灌溉,以维持其正常生长;（2）供试草坪草年需水总量在1 000 mm左右,66%的需水量集中在6—9月4个月内。在水资源紧缺的北方城市绿地建设中,不宜大面积配置草坪草;（3）草坪草的灌水周期以5 d,次灌水量33 mm较为适宜。 相似文献
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通过田间小区试验,研究膜下滴灌条件下农田施用生物炭0 t/hm2(A0)、15 t/hm2(A15)、30 t/hm2(A30)和45 t/hm2(A45)后玉米各生育期土壤含水率、温度和有机质及速效养分含量的变化规律.试验结果表明:在每个生育期,各处理耕层土壤含水率均随生物炭施用量增加呈先增加后减少的趋势,且均高于对照.在玉米拔节期、抽雄期和灌浆期差异性显著,且显著相关,其中A30处理增幅最大,达13.74%;在玉米三叶期和拔节初期,施用生物炭显著提高土壤表层温度,且呈正相关;在抽雄期、灌浆期和成熟期,土壤表层温度依次为A30>A0>A45>A15,与施炭量没有表现出显著相关;耕层土壤有机质和有效磷含量随施炭量增加而显著增加,且均高于对照,与施炭量表现出极显著相关;整个玉米生育期,相比对照A0,处理A15、A30和A45有机质最大增幅分别为:14%、20%和58%,有效磷最大增幅分别为:62%、99%和113%;施用生物炭后,各处理均显著提高了耕层土壤碱解氮和速效钾含量,相比对照A0,处理A15、A30和A45碱解氮的最大增幅分别为13%、17%和10%,速效钾的最大增幅分别为:35%、48%和63%.综上所述,膜下滴灌条件下适量施用生物炭可有效增加耕层土壤含水率、土壤温度和有机质及速效养分,生物炭具有一定的保水、保温、保肥特性,有利于提高土壤水、肥利用率. 相似文献
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