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101.
翅碱蓬野外光谱对土壤化学性质变化的响应   总被引:2,自引:0,他引:2  
[目的]研究翅碱蓬群落特征以获取下方土壤的化学性质。[方法]通过野外采集的17个翅碱蓬野外光谱数据和相应土壤样品的理化分析数据,探讨了土壤化学性质和翅碱蓬野外光谱之间的关系。[结果]翅碱蓬二阶导数光谱1121nm波段可以用来反映土壤有机质和全氮的含量变化,二阶导数光谱1208nm波段可以很好地反映土壤全磷的含量变化,一阶导数光谱353nm波段可以很好地反映土壤速效钾的含量变化,二阶导数光谱724nm波段可以很好地反映土壤pH值的变化,而反映土壤盐分含量变化最好的为一阶导数光谱950nm。[结论]该研究为利用遥感技术进行翅碱蓬覆盖区域土壤化学性质监测奠定了基础。  相似文献   
102.
追施氮肥对盐地碱蓬生长及其改良盐渍土效果研究   总被引:5,自引:0,他引:5  
为了研究追施氮肥对盐地碱蓬生长及其对盐渍土改良的影响,通过田间小区试验研究了不同追施氮量(0~450 kg/hm2)对盐地碱蓬生长、离子累积以及盐渍土修复的影响。结果表明,追施氮肥能够提高盐地碱蓬茎秆、籽粒和叶片的生物量;在0~450 kg/hm2范围内,盐地碱蓬的各部分生物量均随着追施氮量呈直线增长的趋势。追施氮肥对盐地碱蓬茎秆、籽粒和叶片中的K+、Na+ 、Ca2+、Mg2+含量无显著影响,但不同器官不同离子含量之间存在较明显的差异。追施氮肥能够增加盐地碱蓬各部分对K、Na 、Ca、Mg的累积;450 kg/hm2施氮量的盐地碱蓬的各离子累积量均较不施氮显著增加。土壤表层的Na+、K+含量随着追施氮量增加而降低。总之,追施氮肥能够促进盐地碱蓬对盐渍土的生物修复,降低土壤中的Na+浓度及其危害。  相似文献   
103.
This paper presented the results from the study of irrigation erosion of irrigated lands in southern Kazakhstan. The main purpose of the work is the conservation of the fertility of irrigated soils, and then the soils of the upper, middle and lower sections of the slopes at the experimental site were studied. Based on field investigations, authors studied the water resistance of aggregates of gray-brown soils and light gray soils before and after irrigation and qualitative indicators of changes in physical and chemical properties of structured soils in irrigation were determined by conventional methods of soil research. The results indicated that the changes in the physical properties of soils by using polymeric compounds created a fundamentally new opportunity to control water erosion of soils.  相似文献   
104.
Suaeda glauca is a potential feedstock for ruminants in north‐east China in areas of increasing salinity. The characteristics of S. glauca pasture from June to October and effects on intake, digestion and blood metabolites in lambs given increasing proportions of S. glauca in the forage component of a mixed hay/concentrate (50/50) diet were evaluated. Harvest date had a significant effect on dry matter (DM) yield. There were significant increases in DM content, total energy, neutral detergent fibre and acid detergent fibre (ADF), but declines in leaf proportion, crude protein, total ash and sodium contents with maturity. Inclusion of 25%S. glauca hay in a diet significantly improved daily intake of DM, organic matter (OM) and energy compared with T0% and T50% groups. Supplementation at 25 or 50% significantly increased the digestibility of energy, DM, OM and ADF compared with the T0% group. Water intake, urinary excretion, water content of fresh faeces and sodium excretion from urine linearly increased with increasing S. glauca content, but potassium excretion from urine decreased. K and Mg serum contents were significantly increased compared with T0% group when S. glauca made up 50% of diet. This study indicates that S. glauca is a suitable hay when added as 25% of the lamb diet.  相似文献   
105.
Na+ ions play an important role in the growth of halophyte. The effect of Na+ ions on nitrate uptake and osmotic adjustment in the euhalophyte Suaeda physophora was investigated under glasshouse conditions. Seedlings were exposed to 1 mmol/L NaCl (control),300 mmol/L NaCl,150 mmol/L NaCl plus 150 mmol/L KCl or 300 mmol/L KCl treatments for 24 d. Dry weight was not affected greatly by different salt treatments,but water content and succulence in leaves of S. physophora were significantly increased at 300 mmol/L NaCl and 150 mmol/L NaCl plus 150 mmol/L KCl treatments. The concentrations of Na+ and NO3’ in leaves of S. physophora were the highest at 150 mmol/L NaCl plus 150 mmol/L KCl,but lowest at 300 mmol/L KCl treatment. Moreover,the increase of NO3’ concentration did not result in the decrease of Cl-concentration at 150 mmol/L NaCl plus 150 mmol/L KCl treatments. The estimated contribution of NO3’ to osmotic potential (CNO3) in leaves of S. physophora was 9.8% at 150 mmol/L NaCl plus 150 mmol/L KCl,and CNa and CCl were 31.0% and 23.3%,respectively. However,CNO3,CNa and CCl were respectively 1.6%,7.9% and 11.9% at 300 mmol/L KCl treatment. It is concluded that Na+ stimulates NO3’ absorption and the stimulation is independent on the internal or the external Cl-concentration in the euhalophyte S. physo-phora. These characteristics may explain the high levels of N in leaves of saline desert plants in arid ecosystem.  相似文献   
106.
新疆5种藜科盐生植物的饲用价值   总被引:2,自引:0,他引:2  
为了研究新疆5种藜科一年生盐生饲草红叶藜(Chenopodium rubrum)、野榆钱菠菜(Atriplex aucheri)、盐地碱蓬(Suaeda salsa)、盐角草(Salicornia europaea)和高碱蓬(Suaeda altissima)的最佳刈割时期和相对饲用价值大小,对其3个不同生育时期(营养期、初花期和结实期)的营养成分含量进行测定分析。结果表明,5种植物在初花期营养价值最高,地上部生物量能够满足载畜需求,因此适宜在初花期开发利用;5种盐生饲草在初花期与苜蓿(Medicago sativa)相比,红叶藜的相对饲用价值最高,之后依次为野榆钱菠菜、盐地碱蓬、高碱蓬和盐角草。野榆钱菠菜、红叶藜和高碱蓬甜菜碱含量丰富,在7%左右,盐角草、红叶藜和野榆钱菠菜草酸盐含量超标。总之,这5种植物均具有一定的饲用开发利用价值,但盐分含量偏高不宜长期单一饲喂反刍动物。  相似文献   
107.
受人类不合理利用和气候影响的综合作用,松嫩草地退化程度逐渐加剧。本研究选取羊草(Leymus chinensis)群落、虎尾草(Chloris virgata)群落、碱茅(Puccinellia distans)群落和碱蓬(Suaeda glauca)群落作为4个草地退化阶段,通过调查植被群落特征、分析土壤理化性质,测定土壤团聚体稳定性指标,揭示草地植被退化过程中对土壤结构的影响。结果表明,随着退化演替的进行,植被生物量、物种多样性指数和总盖度总体上均呈现为降低的趋势;土壤含水率、有机质含量和全氮均降低,而pH和容重均增加,且4种退化演替阶段的土壤pH均高于8.0;土壤水稳性团聚体的粒径分布中微团聚体(0.25mm)所占比例增加,大团聚体(0.25mm)所占比例和水稳性团聚体的稳定性递减,且在同一退化阶段的0-30cm各土层呈现出水稳性团聚体的稳定性随土层深度增加而稳定性递减的趋势。研究结果对揭示松嫩草地不同退化阶段土壤团聚体稳定性特征以及退化草地恢复重建均有重要指导意义。  相似文献   
108.
田埂碱蓬带对棉田多异瓢虫种群发生的调控作用   总被引:2,自引:2,他引:0  
【目的】 分析田埂碱蓬带对棉田多异瓢虫种群发生的影响,为合理利用非棉田生境实施棉蚜的生态治理提供科学依据。【方法】 采用田间种群系统调查和天敌控害功能罩笼评价。【结果】 田埂碱蓬带是棉田多异瓢虫的重要来源;有碱蓬带的棉田中多异瓢虫种群密度、多异瓢虫与棉蚜的益害比均高于没有碱蓬带的对照棉田,其中多异瓢虫平均密度是对照棉田的1.9倍、益害比是对照棉田的8.8倍;利用罩笼进行天敌隔离处理,第7和14 d处理组(封闭罩笼)棉花上棉蚜种群增长率均显著高于开放罩笼的对照组;有碱蓬带的棉田中捕食性天敌对棉蚜的控害指数显著高于对照棉田。【结论】 棉田田埂碱蓬带能有效增加棉田中多异瓢虫种群密度并提高益害比,对控制棉田棉蚜发生发挥着重要作用。碱蓬在天敌保育与控害中有重要作用,棉田周边予以留种。  相似文献   
109.
运用高光谱遥感技术分析地物特有的光谱特征可以有效地对地物进行识别。以河北省唐山市曹妃甸湿地为研究对象,使用SR2500便携式地物光谱仪测定了2种典型湿地植被——翅碱蓬[Suaeda salsa (L.) Pall.]和芦苇[Phragmites australis(Cav.)Trin.ex Steud.]的光谱特征,并对2种湿地植被的原始反射率光谱曲线和经过包络线去除法变换后的反射率光谱曲线进行研究。结果显示:由于包络线去除法的限制,在340~380 nm和716~1 020 nm波段范围内,分析芦苇原始光谱曲线更容易区分植被所处的生长期,在340~595 nm和710~920 nm波段范围内,分析翅碱蓬的原始光谱曲线更有利于区分所处的生长期,且2种植被生长旺盛期的反射率均高于生长末期。在508、550、678 nm处利用包络线去除法能够更好地区分芦苇不同生长阶段,在638、678 nm处利用包络线去除法能更好地区分翅碱蓬不同生长阶段。芦苇在绿光波段550 nm处出现明显的反射峰,而翅碱蓬在红光波段638 nm处出现明显的反射峰,这使得2种植被经过包络线去除处理后更好区分。在753~1 020 nm波段范围内,分析原始光谱曲线更适于区分芦苇和翅碱蓬,且芦苇的反射率高于翅碱蓬。  相似文献   
110.
Extremely saline soils are very harsh environments for the growth and survival of most plant species, however, halophytes can grow well. The underlying mechanism of halophyte to resist high saline is not well understood by us. This study was conducted at the potash mine near the Lop Nur, China, where the effects of the halophyte Suaeda salsa L. on the saline-alkaline soils and its growth and sustainability were investigated. Four plots(in which the salt encrustation layers were removed), with different soil treatments were evaluated:(1) undisturbed soil, with no additional treatment(T1);(2) the slag soil zone, in which a 40-cm layer of slag was placed on the undisturbed soil surface(T2);(3) slag+sandy soil, in which a 20-cm layer of slag was placed in the lower layer and 20 cm of sandy soil, taken from an area about 70 km away from Lop Nur potash mine, where Tamarix species were growing, was placed in the upper layer(T3); and(4) a 40-cm sandy soil layer taken from the area where Tamarix species were growing was placed on undisturbed soil(T4). Soil nutrient contents increased in the four treatments, but salt content only decreased in the T1 treatment. Salt content in the T4 treatment increased over the two-year period, which may be partly attributed to salt deposition from wind-blown dust within the mine and salt accumulation within the surface soil(0–20 cm) in response to high evaporative demands. The S. salsa plants exhibited greater improvements in growth under the T4 treatment than under the T1, T2, and T3 treatments, which demonstrated that low levels of salinity are beneficial for the growth of this species. The T1 treatment was sustainable because of its low cost and superior soil improvement characteristics. Therefore, S. salsa plants not only reduced soil salinity and increased soil nutrient levels, but also ameliorated the plant growth environment, which would be beneficial for both the ecological restoration of the Lop Nur area and similar areas throughout the world.  相似文献   
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