Abstract:In order to learn how the organic manure application influences the structural characteristics of humic acids in soils, a comparative study was initiated by the method of ¹H-NMR spectra of humic acids separated from the soils (brown soil, meadow soil and paddy soil) with and without organic manure applications (pig manure, corn stalk and rice straw) in field and incubation experiments. The results obtained are summarized as follows:In the solvent system of DMSO-d₆, the absorption peaks of ¹H-NMR spectra were 0.8, 1.2, 3.4, 3.7, 4.4, 6.7, 7.2 and 8.1 ppm. The absorption peaks of 0.8 and 1.2ppm were the contribution of-CH₃ and polymethylene chain(-CH₂-)_n in saturated hydrocarbons respectively; the signals of 3.4, 3.7 and 4.4ppm were due to the H connected with the carbons in carbonhydrate (α-CH;and the peaks at 6.7, 7.2 and 8.1ppm were generally assigned to aromatic H and-COOH (Ac-H).In the solvent system of NaOH-d₁, signals at 1.8, 2.1,and 2.4ppm. were found. It was suggested that these arise from protons attached to carbon a to aromatic ring or other unsaturated groups and α-CH or β-CH in indanes and tetralins of the humic acid.Application of organic manures led to the increase in the relative content of aliphatic H (ali-H).However, the methylene chains (n value) became shorter after organic manure application. On the other hand, the content of aromatic protons (Ar-H) and aromaticity (faH) in humic acids decreased because of organic manure application, which resulted in the increase in the ratio of aliphatic H to Ar-H in the humic acids. Results also showed that pig manure (PM) was more effective than corn stalk (CS) or rice straw (RS) in raising the proportion of aliphatic chain hydrocarbons in humic acids. Whereas CS and RS were more effective in increasing the relative content of carbohydrates in humic acids.

Abstract:A quantitative method of remote sensing for soil erosion is described in this paper. Although form of the model for monitoring losses in the method is the same as the USLE and RUSLE, the formula and algorithms for model factors are generated from loss data observed in our country. Therefore, it is more applicable to loss regions in our country, and suits personal computer proccssing of the GIS and remote sensing data. The results of its application which include the total loss of region, the area of soil loss grades, the soil erosion map and the forecast map of soil conservation, are more accuracy and useful than those of existing methods for the conventional survey and qualitative remote sensing.

Abstract:This paper deals with the primary and secondary mineralogical properties of seven pedons of albic soils from the northern subtropical region of China. The contents of heavy and light minerals show that the soils inherit the parent material properties, the parent material between albic E horizon and argillic horizons are lithologically uncountinous, and the former horizons are weathered strongly than latter ones. The surface of the arenaceous quartz shows albic E horizons result from the loess reaccumulation. Hydromica dominates the clay fraction of albic soils, the kaolinite formation and clay mineral crystallinity show the desilicification and depotassication, the clay minerals can collapse to some extent. The dominant iron oxides are hematite and geothite, these iron oxides are proved to have formed under the conditions consistent with present ones.

Abstract:The clay mineral composition, canon exchange capacity, the quantity of charge and phosphorus adsorption of 21 soil layers from five soil profiles at different altitudes of the Mufu Mountain were measured. The results indicated that with the increase of the altitude, the type of layer silicates varied, and the contents of the active iron and aluminum oxides and organic matter were raised. As a result, the surface properties and anion adsorption changed correspondingly. These changes involved the increase of CEC and AEC, the strengthening of variable charge characteristic, the increase of phosphorus sorption capacity and the decreasing of phosphorus desorption ratio.

Abstract:The genetic characteristics of the soils under coniferous forest in the north western part of Altai Mountains were studied in comparison the podzolic soil and dark brown soil in the eastern part of China. There exists distinct difference between the soils under the coniferous forest and the podzolic soild and dark brown soil.The frigid and moist hydrothermal condition and seasonal freezing layer have important effect on the characteristics of the soil. So the soils under the forest should be called cold brown soil (brown coniferous forest soil).

Abstract:Effect of irrigation water quality on soil chemical characteristics and on crop growth was studied in this work. The salt content and sodium adsorption ratio (SAR) of irrigation water were considered to be two main indexes which were combined in the 16 treatments of irrigation water quality in the experiment. Results showed that salts of irrigation water were accumulated and leached alternately in the soil. When salt content of irrigation water was below 3.0g/L, the salt was kept balanced in soil profile. When the salt content of irrigation water was more than 3.0g/L, the salt was accumulated in the soil, even resulting in the medium secondary salinization. High SAR and high Na₂CO₃ in irrigation water can cause Ca²⁺ and Mg²⁺ to form sediment of CaCO₃ and MgCO₃ to decrease Ca²⁺ and Mg²⁺ concentration and to increase Na⁺ concentration in the soil solution. Thus SSP, SDR and SAR were risen. As a result ESP increased in the soil. When the SAR of irrigation water was more than 14, and the salt content was more than 3.0g/L or 4.0g/L, the growth and yield of soybean and wheat were influenced, a medium or strong soil secondary alkalization occurred.

Abstract:Effect of long-term fertilization on components and changes of phosphorus in fluvo-aquic soil was studied in Tianjin during 1979-1993. Results showed that inorganic phosphorus was predominant, in which Ca-P occupied the largest percentage, O-P was second only to Ca-P and only small part was the Al-P and Fe-P. Long-term fertilization could significantly influence both the content of soil available P and the range of its changes. The effects of chemical phosphorus were more obvious than those of organic sources. The increasing and decreasing of soil available P depended heavily on whether chemical phosphorus was applied or not, soil available p increased or decreased at the rate of 1 mg/kg when 45kg P/ha was added or removed. In addition, our study also suggested that the changes of soil available P differed with the periods of experiment at time. Generally speaking, soil available P changed largely in the first two years, and the changes became smaller in the later 6-8 years, finally it remained in a normal value with quite small changes. Soil phosphorus could be balanced in 15 years when 18 kg/ha. year P₂O₅ was lied for per 100 kg of grain yield under the wheat-corn cropping system with the grain yield of 11400kg/ha in total.

Abstract:5-year-fixed experiments indicated that spontaneous nutrient-suppling capacities of typical black soil in Song Nen Plain were: nitrogen, around 90%; phosphorus, over 95%; and potassium, 100%. The amounts of N, P and K released from farmland were 55-99 kg/ha·year, 14-26 kg/ha·year and 48-93 kg/ha·year seperately. Although black soil farmland has rather high potential fertility, its dependence on fertilization is rising gradually. The spontaneous supplying capacity of nitrogen decreased from 90% to 60% in the treatment with no nitrogen appling during the 5 years, and that of phosphorus declined from 95% to 80-90% in the treatment without phosphorus application during the 5 years.

Abstract:If the mechanisms of different things can be described by the mathematical models whose function forms are exactly same, we believe that there is a mechanism similarity among the things. The mechanism similarity may aid our scientific inquiries in mechanistic modelling. The microorganisms of degrading organic chemicals are mechanistically similar to the predator populations in the Volterra model of interacting populations, but the variance of concentration of the organic chemicals is mathematically different to that of density of the prey populations in the Volterra model. The degradation rate of organic chemicals may be described as:
-dx/dt=jx+kxm
where x is the concentration of organic chemical at time t, m is the number of microorganisms capable of degrading the organic chemical at time t, and j and k are the nonbiological (i. e. chemical) and biological degradation rate constants respectively. The contribution of biological factors to degradation rate is greater by far than that of nonbiological factors within the range of ordinary growth temperature. In this case, the equation may also be written as:-dx/dt=kxm. This paper discusses some methods to express m, thereby expressing the degradation rate as a form that can be integrated.

Abstract:The effect of chlorobenzene and nitrophenol on soil biological activity was studied through analyzing soil respiration intensity, microbial numbers and soil enzyme activities. The results showed that the effect of chlorobenzene and nitrophenol on soil biological activity was complex. Chlorobenzene below 200mg/kg could stimulate soil respiration and total numbers of bacteria, actinomyces and fungi, but inhibit amoniafying bacteria, nitrifying bacteria and denitrifying bacteria. The chlorobenzene below 200mg/kg also stimulated the activities of urease and dehydrogenase but slightly inhibited the activity of sucrase. Nitrophenol below 200mg/kg inhibited the growth of almost all microbes and the activities of several enzyme.

Abstract:A strongly salined coastal soil was reclaimed by fish culture with accumulated rain water together with additional irrigation using slightly salined river water. The rate of salt leaching was distinctly decreased after the salt contents of the soils declined to certain values. Two years later, in the same soils, a new culture model of mixed culture of fish and barley (MC)¹⁾ was set up and compared with only barley culture (BC)²⁾ and with only fish culture (FC)³⁾ to exame the effect of saline soil reclamation. The results obtained in the following three years were as follows. 1.The maximum rate of salt leaching, the biggest decrease of Na⁺/Ca⁺⁺ and the distinct enrichment of Ca⁺⁺ in surface soil (0-20cm) were obtained in the soils of MC. 2. Better soil fertility indexes, such as soil physical and chemical properties, could also be found in the soils of MC. Thus, soil organic carbon of MC was 1.48 times that of BC, the ability of nitrogen supply was in the order of MC>BC>FC, and the biggest activity of soil urease was obtained in the soil of MC, which was closely related to the fertility of coastal saline soil.

Abstract:The environment and nutrient status of the rhizosphere were studied using three apple rootstock seedlings, Malus hupehensis Reld, M. prunifolia Bork and M. sieversii Roem. The results showed that pH and Eh decreased and N, P and K were depleted in the rhizosphere compared with the bulk soil. Ca and Mg were enriched in the rhizoplane. The rhizosphere range of apple rootstock seedlings was mostly about 2-3mm from root surface, sometimes it might reach to 4-5mm. Results also showed that different species had different environments and nutrient status of the rhizosphere.

Abstract:In the work, the reason of ginseng red skin sickness in albic soil were studied by the ecological quadrat methods. Results showed that active reducing organic substances could form in bed soil under moisture capacity and well aerated conditions, and they promoted the activation of iron and manganese oxides and enhanced the accumulation of divalent iron and manganese. Ginseng red skin sickness could be attributed to the oxidizing and depositing of ferrous iron in epidermis of ginseng root or to the protective reaction of ginseng root to poisonousnss of ferrous ions. The results also showed that divalent manganese inhibited ginseng red skin sickness. In the bed soil, active reducing substances is the induced factor and ferrous ions is the leading factor in the occurrence of ginseng red skin sickness.

Abstract:The suitability of seven methods for chemical extraction of available potassium in the upland field was studied by using exhaustion pot experiment as the reference standard. The results were summarized as follows: 1.Available K absorbed by plants mainly Came from the nonexchangeable K, which was the main source of K takd up by plants. 2. Der termination results of correlation coefficients between four reference standards of pot experiment and results of seven chemical methods showde that correlation between cold 2 mol/L HNO₃ method and Cation-exchange resion bag method was highly significant (0.953 and 0.903 average). 3. The correlation between the nonexchangeable K extracted by cold 2 mol/L HNO₃ method and Cation-exchange resin bag method and the amount of nonexchangeable K absorbed by plant was highly singificant. 4. Both of the cold 2 mol/L HNO₃ method and Cation-exchange resin bag method could be recommended as the methods for the determination of available potassium in upland field, but the Cold 2 mol/L HNO₃ method was more simple and convenient than the Cation-exchange resin bag method.

Abstract:淮南市位于安徽省北部,是一个年产近3000万吨的大型煤炭生产基地,素有百里煤城之称,面积约2000km²,人口近250万。全区有数百家大中型企业,包括一些国有大型骨干企业(如120万千瓦的火力发电厂、大型化肥厂、洗煤厂等)。由于长期的煤炭开采和工矿企业的生产规模日益扩大,使得全区土壤受到了不同程度的污染。

Abstract:关于水合物氧化物对重金属离子的专性吸附的机理,虽然目前看法不同,但对专性吸附在方法论上的定义则是基本一致的,即:在中等或高浓度的碱或碱土金属离子存在时,则氧化物对微量重金属产生吸附作用^[1]。很多资料也表明随加入的碱或碱土金属离子浓度增加,重金属离子吸附量减少^[2,3]。这些也被看作是专性吸附方法论定义的合理性的证据,因为在上述条件下,重金属吸附量的减少被认为是碱或碱土金属离子抑制了其非专性吸附的结果。