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研究了铜、锌在双城、海伦、方正农田黑土中的吸附解吸行为.3地土壤吸附Cu2+、Zn2+的量均随着平衡液中Cu2+、Zn2+质量浓度的增加而增大.双城、海伦、方正农田黑土对Cu2+的吸附解吸行为用Freundlich方程拟合最佳,吸附态Cu2+的解吸有明显滞后现象,而且3地土壤吸附态Cu2+的解吸率均较低.供试土壤对Zn2+的吸附行为用Freundlich方程拟合最佳,而对Zn2+的解吸行为用Langmuir方程拟合最佳.  相似文献   
2.
Top phaeozem samples were collected from Nenjiang County (in Heilongjiang province) to Changtu County (in Liaoning province) in Northeast China every 6 km by using global positioning system (GPS) and analyzed for their content of organic C, total N, total P, organic P, and the organic to inorganic P (Po/Pi) ratio. The content of organic P was significantly correlated with organic C and total N contents (P<0.01). The contents of organic P and total P and the Po/Pi ratio were significantly correlated with latitude (P<0.01), with r 2 coefficient of 0.59, 0.46, and 0.36, respectively. Since inorganic P content was not correlated with latitude (r 2=0.07) and the contents of organic P and total P were significantly correlated (P<0.01, r 2=0.70), it is reasonable to hypothesize that organic P can play an important role in the spatial differentiation of total P and the Po/Pi ratio. Probably, the causes of these spatial differentiations were the effects of climate and reclamation variations along the North–South transect.  相似文献   
3.
Repeated applications of bordeaux mixture (a blend of copper sulfate and calcium hydroxide) and pyrethroid insecticides (Pys) have led to elevated copper (Cu) and Pys concentrations in vineyard surface soils. To understand the potential influence of Cu on the fate of Pys in the soil environment, we selected two Pys, cypermethrin (CPM) and lambda-cyhalothrin (λ-CHT), and two typical Chinese vineyard soils, Haplic Acrisol and Luvic Phaeozem, as experimental samples. The dissipation experiment was conducted at room temperature in the dark, and the transport of both Pys through the soils was investigated using soil thin-layer chromatography. The results showed that the transport of Pys in both soils increased as the Cu2+ concentration increased from 0 to 100 mg L-1 , and Pys were more transportable in Haplic Acrisol (HA) than in Luvic Phaeozem (LP) under the same experimental conditions. For CPM, only 100 mg L-1 of Cu2+ significantly (P<0.05) increased Pys transport through both soils relative to water. Lambda-CHT was significantly (P<0.05) transported through HA by all the Cu2+ concentrations compared to water, and all but the 1 mg L-1 of Cu2+ significantly (P<0.05) increased the transport of λ-CHT through LP relative to water. However, the dissipation rates of CPM and λ-CHT decreased with the addition of Cu to soils. Our findings suggest that the risk of groundwater contamination by Pys increases in the soils with elevated Cu concentrations.  相似文献   
4.
自然降雨对黑土地表氮素养分流失的影响   总被引:9,自引:1,他引:9  
针对黑土利用现状,在吉林农业大学黑土区选择不同利用方式的玉米地、休闲地、果园、草地,并在玉米区进行了不同数量的施肥。通过野外试验,采集2002年度5~10月历次自然降雨(共7次)产流及泥沙样品,同时采集降雨前后的耕层土壤样品,研究了黑土区地表径流对氮素养分特征及肥力退化的影响。结果表明:侵蚀泥沙的粒级分布特征表现为(1~0.05mm与0.05~0.01mm)2个粒级接近80%。土壤TN流失随植被覆盖度增加而减少;径流矿质氮流失随植被覆盖度增大并无减少,即植被覆盖度并不能减少土壤矿质氮流失;不同的植被类型,NH46^+—N流失相差较大,NO3^-—N相差较小。在土壤养分含量差异不明显时.施肥量对黑土径流氮素养分流失的影响表现为泥沙TN、径流TN浓度均随氮用量增加而增加;当氮肥施用量为N2(98kg/hm^2),磷肥(44kg/hm^2)施用量为P2时,泥沙和径流氮素流失相对较小。  相似文献   
5.
吉林省主要耕作土壤中结合态腐殖质组成特征的研究   总被引:6,自引:0,他引:6  
通过化学分析方法研究了吉林省主要作土壤白浆土、黑土、黑钙土的结合态腐殖质的组成特征。结果表明:3种土壤中有机质有72%-95%以结合态开式存在,土壤结合态腐殖相对含量和组成因土类的不同而异,其中黑土相对含量最高,黑钙土最低,结合态腐殖质组成(胡敏酸/富里酸:HA/FA)呈现地带性分布特征,即由中部向西部和东部呈递减的趋势;土壤中腐殖均以松结合态为主,白浆土、黑土、黑钙土下层(20-40cm)土壤结合态腐殖质的相对含量和HA/FA均高于上层(0-20cm)。随土壤粒径的增大,3种土壤的结合态腐殖质都呈规律性的变化,其中白浆土结合态伎俩南相对含量增加,而黑土和黑钙土相对含量减少。随土壤肥力水平的提高,白浆土,黑土结合态腐殖质相对含量增加,其中黑土3种结合态腐殖质的相对含量变化均呈规律性,松结合态,紧结合态腐殖质相对含量随肥力水平提高而增加,而稳结合态的腐殖质相对含量则相反;黑钙土只有紧结合态腐殖质相对含量随肥力水平的提高而降低,3种土壤结合态腐殖质的HA/FA均随土壤肥力水平的增加而增大。  相似文献   
6.
为了研究激光扫描技术应用于土壤侵蚀监测的可靠性,利用3D激光地貌分析仪对黑龙江省水土保持科技示范园内坡耕地径流小区土壤侵蚀进行监测.采用恒定降雨强度(20、40、60、80、100和120 mm/h)对径流小区进行连续6次等历时(30 min)人工降雨,每场降雨前后使用3D激光地貌分析仪对小区内不同位置的坡面形态进行扫描,并与集流桶收集土壤侵蚀量进行对比分析.结果表明:3D激光扫描分析法与集流桶测量法得到的土壤侵蚀量之间具有良好的线性相关关系,3D激光地貌分析仪用于径流小区内土壤侵蚀测定具有较高的精度与可靠性.  相似文献   
7.
In a long-term field trial (Halle, Germany, founded in 1949 by K. Schmalfuß, soil type Haplic Phaeozem), the effects of different mineral and organic fertilization on dry matter yields, soil C and N contents and N balances were investigated. Over a period of 60 years, yields increased on average in all cultivated crops (winter and spring cereals, potatoes, sugar beets, silage maize), even without any fertilization. Nitrogen deficiency in unfertilized and PK treatments caused strong decreases in yield (up to 48%) in comparison with the N2PK standard treatment. The effect of omitting K or P supply was smaller (up to 18% and 7% yield reduction, respectively). The highest yields were obtained with high mineral N + PK application and (except winter wheat) with farmyard manure in combination with mineral fertilization. The N balances were negative in all treatments. However, if N immission from the air (40 kg ha?1 a?1) was included in the calculation, N balances were negative only in low N treatments. The soil C and N contents increased up to 1975. A considerable decrease has been seen since about 1985. The highest soil C and N contents were observed in the farmyard manure treatments. In addition to fertilization effects, this development of soil properties reflects changes in environmental pollution, climatic changes, as well as shifts in cultivation methods like tillage depths, over recent decades.  相似文献   
8.
不同利用方式及施肥对黑土地表磷素养分流失的影响   总被引:6,自引:2,他引:6  
本文针对黑土利用现状,在吉林农业大学教学试验场黑土区选择不同利用方式的玉米地、休闲地、果园、草地,并在玉米区进行了不同数量的施肥。通过野外试验,采集2002年度5~10月历次自然降雨(共7次)产流及泥沙样品,同时采集降雨前后的耕层土壤样品,研究了黑土区地表径流对磷素养分特征及肥力退化的影响。结果表明:径流TP流失比和DP流失比随覆盖度都表现为先增加后逐渐降低;不同利用方式表层土壤的TP和DP相差很大,就全磷富积表现为果园>草地>玉米地>休闲地,可溶性磷的富积却表现为:休闲地>玉米>果园>草地;随P肥用量的增加而径流磷素(TP、DP)浓度及径流磷素流失量也增加;流失泥沙TP浓度随着磷素施入的增加而增加;泥沙磷素浓度、泥沙磷素流失量均比CK大,但泥沙流失量均比CK小;增施氮磷虽能增加作物的产量,但N、P施用量必须适度,从试验期间径流、泥沙的TP、DP流失量观测,可以初步得出黑土氮磷配合施肥的宜于选配的方案是B5区N98P44N570。  相似文献   
9.
研究不同施肥处理对农田黑土纤维素酶、过氧化物酶和多酚氧化物酶活性的影响。结果表明,不同施肥处理下0~20 cm土壤纤维素酶活性、过氧化物酶活性有机肥与化肥配施(NPK+M)休闲地(FW)单施化肥(NPK)不施肥(CK),21~40 cm土壤NPK+MNPKFWCK处理;多酚氧化酶的活性0~20 cm为FWNPKNPK+MCK处理,21~40 cm为CKFWNPKNPK+M处理。在玉米的生育期内,土壤纤维素酶和多酚氧化酶的活性在出苗后50 d(拔节期)达最大;过氧化物酶的活性在出苗后15 d(苗期)最大。施肥有利于提高土壤纤维素酶、过氧化物酶和多酚氧化酶的活性,有机无机肥配合施用效果最佳。  相似文献   
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