渭北果园土壤有机质及酶活性研究

为了探讨渭北果园土壤生物质量演化趋势,分析制约地区苹果可持续发展的土壤因素,在渭北旱塬果区选择了<10 a、10~20 a、>20 a园龄段苹果园各3个,选用农田土壤作为对照,研究0~100 cm范围内土壤有机质、过氧化氢酶、脲酶、碱性磷酸酶活性的变化趋势。结果表明,随着果树种植年限的增加,果园土壤有机质含量仅在表层0~20 cm有不同程度地累积趋势,且在>20 a果园累积较为明显;20~40 cm土层处有机质呈现在植果初期递减,20 a后逐渐增加的趋势;果园土壤3种酶活性变化差异主要体现在0~40 cm土层范围,过氧化氢酶活性在0~40 cm呈现递减趋势,且在0~100 cm土层显著高于农田土壤;脲酶活性在0~40 cm有不同程度递增过程,碱性磷酸酶活性在0~40 cm也呈现出相对增高的态势。相关性分析表明土壤有机质与3种酶之间存在着极显著相关。由此得出,渭北地区果树对土壤生物质量的影响主要体现在0~40 cm范围,果园土壤过氧化氢酶活性显著递减和表层土壤脲酶活性增加可能会对苹果树生长产生一定影响。     

Soil fixation and erosion control by Haloxylon persicum roots in arid lands,Iran

Vegetation roots contribute to soil fixation and reinforcement, thus improving soil resistance against erosion. Generally, the amount of soil fixation presented by roots mainly depends on root density and tensile strength. In the present study, we conducted the research in order to further understand the biotechnical properties of Haloxylon persicum and also to quantify its role in increasing soil cohesion in arid lands of Iran. Ten H. persicum shrubs were randomly selected for root distribution and strength investigations, in which five samples were set on flat terrain and other five samples on a moderate slope terrain. The profile trench method was used to assess the root area ratio(RAR) as the index of root density and distribution. Two profiles were dug around each sample, up and downslope for sloped treatment and north and south sides for flat treatment. The results showed that RAR increased with increasing soil depth and significantly decreased in 40–50 cm layers of downhill(0.320%) and 50–60 cm for uphill(0.210%). The minimum values for the northward and southward profiles were 0.003% and 0.003%, respectively, while the maximum values were 0.260% and 0.040%, respectively. The relationship between the diameter of root samples and root tensile strength followed a negative power function, but tensile force increased with increasing root diameter following a positive power function. The pattern of increased cohesion changes in soil profile was relatively similar to RAR curves. The maximum increased cohesion due to the presence of roots in uphill and downhill sides were 0.470 and 1.400 kPa, respectively. In the flat treatment, the maximum increased cohesions were 0.570 and 0.610 kPa in northward and southward profiles, respectively. The analysis of variance showed that wind and slope induced stresses did not have any significant effect on the amount of increased cohesion of H. persicum. The findings served to develop knowledge about biotechnical properties of H. persicum root system that can assist in assessing the efficiency of afforestation and restoration measures for erosion control in arid lands.     

Prioritizing woody species for the rehabilitation of arid lands in western Iran based on soil properties and carbon sequestration

Plants are an important component in many natural ecosystems. They influence soil properties, especially in arid ecosystems. The selection of plant species based on their adaptations to site conditions is essential for rehabilitation of degraded sites and other construction sites such as check-dams. Other factors to be considered in species selection include their effects on soil properties and their abilities to meet other management objectives. The purpose of this study was to assess the effects of native (Populus euphratica Oliv. and Tamarix ramosissima Ledeb.) and introduced (Eucalyptus camaldulensis Dehnh. and Prosopis juliflora (Swartz) DC.) woody species on soil properties and carbon sequestration (CS) in an arid region of Iran. Soil sampling was collected at three soil depths (0-10, 10-20 and 20-30 cm) at the sites located under each woody species canopy and in an open area in 2017. Soil physical-chemical property was analyzed in the laboratory. The presence of a woody species changed soil characteristics and soil CS, compared with the open area. For example, the presence of a woody species caused a decrease in soil bulk density, of which the lowest value was observed under E. camaldulensis (1.38 g/cm³) compared with the open area (1.59 g/cm³). Also, all woody species significantly increased the contents of soil organic matter and total nitrogen, and introduced species had more significant effect than native species. The results showed that CS significantly increased under the canopy of all woody species in a decreasing order of P. euphratica (9.08 t/hm²)>E. camaldulensis (8.37 t/hm²)>P. juliflora (5.20 t/hm²)>T. ramosissima (2.93 t/hm²)>open area (1.33 t/hm²), thus demonstrating the positive effect of a woody species on CS. Although the plantation of non-native species had some positive effects on soil properties, we recommend increasing species diversity in plantations of native and introduced woody species to provide more diversity for the increased ecosystem services, resilience, health and long-term productivity.     

陕西渭北地区苹果园土壤有机质现状评价

为了了解陕西省渭北苹果园土壤有机质含量现状,选取该区有代表性的56个果园,调查了施用有机肥料的种类、方法、施肥量和苹果产量,分析不同深度的土壤有机质含量。结果表明：平均施肥量及有机质含量与苹果产量呈正相关;渭北地区苹果园土壤0～40cm土层有机质含量平均值为1．26％,总体处于中等水平,变幅在0．86％～2．17％;有机质0～40cm含量（1．26％）明显大于40～60cm含量（0．90％）,且不同地区含量差别较大：不同地区土壤有机质的垂直分布存在差异。最后,根据试验结果提出了陕西省苹果园土壤有机质含量分级指标。     

Soil quality of semi-arid conservation reserve program lands in Eastern New Mexico

A study was conducted to evaluate selected soil quality indicators in lands that have been in Conservation Reserve Program (CRP), which is a federal program in the United States offering annual rental payments and cost-share assistance to farmers who establish long-term vegetation covers on their erosion prone lands. The study site has semi-arid climate, and soils with grass vegetation covers for 15 years were compared with adjacent cultivated croplands that have never been in the CRP. Field measurements were performed and surface soil samples (0–0.15 m) were collected from multiple sites having either coarse textured or fine textured soils. Soil measurements assessed included bulk density (BD), penetration resistance (PR), wet aggregate stability (WAS), dry aggregate size distribution (DASD), soil organic matter (SOM), permanganate oxidizable carbon, nitrate nitrogen, extractable potassium and phosphorus, electrical conductivity, pH, sodium adsorption ratio, and soil micronutrients (copper, iron, manganese, and zinc). Results showed a significant effect of CRP management compared to the cropped fields for BD, WAS, and PR only, with the CRP fields being less compacted and having higher WAS than the cropped lands. CRP land did not significantly differ from cropped lands in SOM and for many other measurements. The effect of soil texture was significant for DASD, SOM, copper, and manganese, with the fine textured soils having more favorable measurements than the coarse textured soils. CRP management did not produce significant increase in topsoil SOM compared to cropped lands of the study area.     

科尔沁地区不同类型沙地土壤饱和导水率特征分析

土壤饱和导水率反映了土壤的入渗性质,是研究水分在土壤中运动规律的重要水力参数。利用Guelph入渗仪测量了科尔沁地区樟子松林、灌木林和草地0-20cm、20-40cm和40-60cm三个不同土层深度的土壤饱和导水率,分析了这三种类型沙地土壤饱和导水率的差异及其随土层深度的变化特征。结果表明:1)平均土壤饱和导水率樟子松林较大,草地次之,而灌木林较小,它们的平均取值在0.63～12.50mm/min范围内;随土层深度增加,樟子松林土壤饱和导水率逐渐增大,而草地的逐渐减少,灌木林的随土层深度变化不大;2)樟子松林和灌木林土壤饱和导水率与容重显著负相关;灌木林和草地土壤饱和导水率与细沙百分含量显著负相关,而与中沙百分含量显著正相关;樟子松林和草地土壤饱和导水率与粗沙百分含量显著正相关。     

Protecting wild yak (Bos mutus) species and preventing its hybrid in China

China has made efforts to protect wild yak (Bos mutus) species and prevent the hybrids between wild yak and domestic yak (Bos grunniens) species.At present,wild yak population of a reasonable estimate would be over 70,000.Due to conservation efforts in environmental protection and ecological construction such as the Wildlife Protection and Nature Reserve Construction Project,the "Grain-for-Green" Project and the Natural Forest Resources Protection Project,the number of wild yaks is increasing.In general,Tibetan Plateau's ecosystem is getting better and its environmental quality shows a gradual improving trend.Tibetan Plateau is one of the world's cleanest regions called as the "Third Pole".In order to preserve the genetic pool of wild yaks,local pastoralists and polices drive off the wild male yaks from the domestic yak herds by making noise (banging washbasins,pots,etc.) or driving cars.Local government also incentivizes the culling of domestic yaks found in wild herds.For the sake of the biological and genetic features of this wild species,and the pastoralist way of life,wild yaks should continuously be protected to keep their genetic integrity.We appeal plans to investigate the gene pollution of wild yaks in some important distribution regions of this species.In the face of hybridizing with domestic yaks,proper guidance is urgently needed to address genetic pollution and protect the genetic integrity of wild yaks.     

干旱区盐渍化荒地不同开垦年限土壤碳氮储量研究

在天山北坡绿洲区分别选取连续开垦3 a、8 a、15 a盐渍化棉田和未开垦的盐渍化荒地,采集0~10、10~20、20~40、40~60、60~100 cm土层土壤样品,测定土壤有机碳、全氮含量。结果表明:盐荒地开垦后棉田0~100 cm土层土壤有机碳含量随开垦年限呈逐渐增加的趋势;开垦后棉田土壤全N含量随开垦年限的增加而增加,但处理间无显著差异;盐荒地与开垦棉田土壤有机碳、全N含量随土层深度增加而降低,其中盐荒地不同土层间土壤有机碳含量差异显著,0~40 cm土层土壤有机碳、全N含量明显高于40 cm以下土层;开垦棉田土壤C/N随开垦年限的增加呈现增加的趋势,盐荒地和开垦棉田土壤C/N随土壤深度的增加而降低,二者之间差异不显著;开垦棉田土壤有机碳储量随开垦年限的增加呈先减少后增加的趋势。结论:干旱区盐荒地开垦后,棉田土壤有机碳、全N含量均随开垦年限的增加而增加,而土壤有机碳储量随开垦年限的增加先减小后增加。盐荒地与开垦棉田土壤有机碳和全N含量随土层深度增加而减少。     

硫酸除氯在含氯土壤有机质测定中的应用

通过对土壤有机质中不同氯离子含量的测定 ,总结出了用提前加H2 SO4方法消除氯离子干扰的检索表。根据该表在测定土壤有机质时 ,用提前加H2 SO4的方法能消除氯离子的部分干扰。试验结果是 :当有机质小于2 3.0 g·kg-1时 ,用提前加硫酸的方法能消除氯离子的最低含量为 4 0 g·kg-1;当有机质为 2 3.0～ 32 .0 g·kg-1时 ,用提前加硫酸的方法能消除氯离子的最低含量为 12g·kg-1;当有机质为 32 .0～ 38.0g·kg-1时 ,用提前加硫酸的方法能消除氯离子的最低含量为 4 g·kg-1。因此 ,在土壤有机质分析工作中 ,对于一般的土壤都可以用提前加H2 SO4的方法来消除氯离子的干扰。     

Contents of soil organic carbon and nitrogen in water-stable aggregates in abandoned agricultural lands in an arid ecosystem of Northwest China

Soil organic matter content in water-stable aggregates(WSA) in the arid ecosystems(abandoned agricultural lands especially) of China is poorly understood. In this study, we examined the WSA sizes and stability, and soil organic carbon(OC) and nitrogen(N) contents in agricultural lands with abandonment ages of 0, 3, 12, 20, 30 and 40 years, respectively, in the Minqin Oasis of Northwest China. The total soil OC and N contents at depths of 0–20, 20–40 and 40–60 cm in abandoned agricultural lands were compared to those in cultivated land(the control). Agricultural land abandonment significantly(P0.05) influenced the distribution of MWD(mean weight diameter), and OC and N contents. There were significant increases in MWD and the proportion of macroaggregates(sizes 0.25 mm) as the age of agricultural land abandonment increased. The effect of abandonment ages of agricultural lands on MWD was determined by the changes of OC and N accumulation in WSA sizes 2 mm. The total OC and N contents presented a stratification phenomenon across soil depths in this arid ecosystem. That is, both of them decreased significantly at depths of 0–20 and 40–60 cm while increased at the depth of 20–40 cm. The WSA sizes 0.053 mm had the highest soil OC and N contents(accounting for 51.41%–55.59% and 42.61%–48.94% of their total, respectively). Soil OC and N contents in microaggregates(sizes 0.053–0.25 mm) were the dominant factors that influenced the variations of total OC and N contents in abandoned agricultural lands. The results of this study suggested that agricultural land abandonment may result in the recovery of WSA stability and the shifting of soil organic matter from the silt+clay(0.053 mm) and microaggregate fractions to the macroaggregate fractions. However, agricultural land abandonment did not increase total soil OC and N contents in the short-term.     

PAM与SAP交并施用对旱区坡耕地氮素淋溶的影响

通过在旱区坡耕地上模拟降雨试验,研究在降雨强度40 mm·h^-1和历时为3 h的条件下,7种线性水溶性高分子聚合物（PAM）和新型节水保水材料（SAP）交并施用方式对径流和氮素淋溶的影响。结果表明：与对照处理（不施用PAM和SAP）相比较,施加PAM和SAP有效减少了径流量和氮素淋溶量,减少的地表径流量达93.29%,相应地降低水中总氮淋溶量达25.58%,保水作用SAP强于PAM;同时,减少的土壤侵蚀量达91.85%,相应地降低泥沙中总氮淋溶量达37.96%;由降雨后土壤剖面养分分布可知,0~15 cm深度土壤的含氮量比对照组高50.24%。说明施加PAM和SAP增加了根系层的持水和保肥能力,降低了土壤养分随水的深层渗漏,且保土作用PAM强于SAP。在坡耕地施加PAM和SAP不但可以减少水土流失,而且能降低土壤氮素的流失,防止肥料对地下水的污染。     

Prediction of soil surface salinity in arid region of central Iran using auxiliary variables and genetic programming

Spatial information on soil salinity is increasingly needed for decision making and management practices in arid environments. In this article, we attempted to investigate soil salinity variation via a digital soil mapping approach and genetic programming in an arid region, Chah-Afzal, located in central Iran. A grid sampling strategy with 2-km distance was used. In total, 180 soil surface samples were collected and then analyzed. A symbolic regression was then adopted to correlate electrical conductivity (EC_e) with a suite of auxiliary data including predicted maps of apparent electrical conductivity (vertical: EC_av and horizontal: EC_ah), Landsat spectral data and terrain attributes derived from a digital elevation model. The accuracy of the genetic programming model was evaluated using root mean square error (RMSE), mean error (ME), and coefficient of determination (R²) based on an independent validation data set (20% of database or thirty soil samples). In general, results showed that EC_ah had the strongest influence on the prediction of soil salinity followed by salinity index wetness index, Landsat Band 3, multi-resolution valley bottom flatness index, elevation, and normalized difference vegetation index. Furthermore, results indicated that the genetic programming model predicted EC_e over the study area accurately (R² = 0.87, ME = ?1.04 and RMSE = 16.36 dSm^?1). Overall, it is suggested that similar applications of this technique could be used for mapping soil salinity in other arid regions of Iran.     

Fate of metsulfuron-methyl in soils in relation to pedo-climatic conditions

The dependence of the behaviour of metsulfuron-methyl on soil pH was confirmed during incubations under controlled laboratory conditions with two French soils used for wheat cropping. The fate of [¹⁴C] residues from [triazine-¹⁴C]metsulfuron-methyl was studied by combining different experimen-tal conditions: soil pH (8·1 and 5·2), temperature (28 and 10°C), soil moisture (90 and 50% of soil water holding capacity) and microbial activity (sterile and non-sterile conditions). Metsulfuron-methyl degradation was mainly influenced by soil pH and temperature. The metsulfuron-methyl half-life varied from five days in the acidic soil to 69 days in the alkaline soil. Under sterile conditions, the half-life increased in alkaline soil to 139 days but was not changed in the acidic soil. Metsulfuron-methyl degradation mainly resulted in the formation of the amino-triazine. In the acidic soil, degradation was characterised by rapid hydrolysis giving two specific unidentified metabolites, not detected during incubations in the alkaline soil. Bound residues formation and metsulfuron-methyl mineralisation were highly correlated. The extent of bound residue formation increased when soil water content decreased and was maximal [48 (±4)% of the applied metsulfuron-methyl after 98 incubation days] in the acidic soil at 50% of the water holding capacity and 28°C. Otherwise, bound residues represented between 13 and 32% of the initial radioactivity. © 1998 SCI     

含氯离子土壤有机质分析方法的初步研究

本文探讨了用提前加Ｈ２ＳＯ４的方法来消除氯离子对测定土壤有机质的干扰。     

Adsorption and degradation of four acidic herbicides in soils from southern Spain

BACKGROUND: Pesticide degradation and adsorption in soils are key processes determining whether pesticide use will have any impact on environmental quality. Pesticide degradation in soil generally results in a reduction in toxicity, but some pesticides have breakdown products that are more toxic than the parent compound. Adsorption to soil particles ensures that herbicide is retained in the place where its biological activity is expressed and also determines potential for transportation away from the site of action. Degradation and adsorption are complex processes, and shortcomings in understanding them still restrict the ability to predict the fate and behaviour of ionisable pesticides. This paper reports the sorption and degradation behaviour of four acidic pesticides in five soils from southern Spain. Results are used to investigate the influence of soil and pesticide properties on adsorption and degradation as well as the potential link between the two processes. RESULTS: Adsorption and degradation of four acidic pesticides were measured in four soils from Spain characterised by small organic matter (OM) contents (0.3-1.0%) and varying clay contents (3-66%). In general, sorption increased in the order dicamba < metsulfuron-methyl < 2,4-D < flupyrsulfuron-methyl-sodium. Both OM and clay content were found to be important in determining adsorption, but relative differences in clay content between soils were much larger than those in OM content, and therefore clay content was the main property determining the extent of herbicide adsorption for these soils. pH was negatively correlated with adsorption for all compounds apart from metsulfuron-methyl. A clear positive correlation was observed for degradation rate with clay and OM content (P < 0.01), and a negative correlation was observed with pH (P < 0.01). The exception was metsulfuron-methyl, for which degradation was found to be significantly correlated only with soil bioactivity (P < 0.05). CONCLUSIONS: Both OM and clay content were found to be important in determining adsorption, but relative differences in clay content between soils were much larger than those in OM content, and therefore clay content was the main property determining the extent of herbicide adsorption for soils of this type. pH was negatively correlated with adsorption for all compounds apart from metsulfuron-methyl. The contrasting behaviour shown for these four acidic pesticides indicates that chemical degradation in soil is more difficult to predict than adsorption. Most of the variables measured were interrelated, and different behaviours were observed even for compounds from the same chemical class and with similar structures.     

干旱区绿洲土壤有机碳高光谱估测及其影响因子分析

为了揭示干旱区绿洲土壤有机碳的分布格局及环境因子的影响,以新疆渭干河-库车河三角洲绿洲为研究区,通过实测土壤高光谱数据以及化学分析获取的剖面土壤有机碳数据,提出了一种土壤光谱和偏最小二乘回归预测模型相结合的土壤有机碳估算方法,并分析了表层土壤有机碳含量与环境因子之间的相关性。结果表明:土壤反射率二阶微分变换优于一阶微分,经二阶微分变换后的光谱可以较好地预测土壤有机碳含量,预测模型的决定系数R~2均大于0.8,RPD均大于1.5,模型具有较高的精度和较好的稳定性。绿洲剖面土壤有机碳含量介于0.172～17.376 g·kg~(-1)之间,且主要集中在0～60 cm;土壤有机碳的变异系数在35%～53%;各层土壤有机碳分布格局相似,绿洲内部明显高于绿洲外围,并均有向表层聚集的趋势。相关分析表明土壤含盐量是影响土壤有机碳含量最重要的环境因子。     

不同管理模式对干旱区草原土壤团聚体稳定性及其理化性质的影响

通过湿筛法,对阿勒泰地区人工草地、禁牧草场、季节草场、弃耕草地和天然草地5种管理模式土壤进行粒径分组及理化性质分析。结果表明:天然草地的有机质含量最高(16.337 g·kg~(-1)),人工草地最低(10.623 g·kg~(-1)),天然草地有机质含量显著高于其它草地(P0.05);土壤大团聚体含量顺序为禁牧草地(29.83%)天然草地(25.33%)季节草地(21.47%)弃耕草地(19.28%)人工草地(9.96%);在0~50 cm土壤深度的各土层上,不同管理模式下土壤水稳性团聚体平均质量直径(MWD)变化规律基本一致,禁牧草地团聚体和几何平均直径(MWD和GMD)值均明显高于其它4种管理模式,人工草地MWD和GMD值最低;大团聚体含量与土壤有机碳(SOC)、MWD和GMD呈显著正相关,相关系数分别为0.402、0.931和0.945,而微团聚体含量与SOC、MWD和GMD呈极显著负相关,相关系数分别为-0.383、-784和-0.779。土壤速效磷与MWD、GMD、SOC和各粒级团聚体相关性不显著。比较几种管理模式,相对于天然草地来说,禁牧草地大团聚体含量是天然草地的1.01倍,说明禁牧的方式更利于土壤团聚体的形成与稳定,而人工草地大团聚体含量则是天然草地的0.39,说明人为干扰对土壤团聚体稳定性的破坏较为严重。     

干旱地区棉田连作对土壤氮素含量及氮转化速率的影响

为研究干旱地区棉田不同连作年限对土壤氮素含量和氮转化速率的影响,选取新疆艾比湖流域内精河县托托乡和农五师91团0、1、5、10、20 a和30 a棉田为研究对象,以棉田连作下土壤理化性质变化为基础,结合土壤氮素含量和氮转化速率,定量研究了连作棉田土壤氮转化速率变化规律及生态驱动因素。结果表明：（1）旱区连作棉田土壤硝态氮为无机氮主要组成,不同连作年限中土壤硝化作用均能将铵态氮转化为硝态氮,年限间差异不显著且硝态氮总量普遍偏低（平均为5.56±0.28 mg·kg^-1）;土壤碱解氮含量均显著低于未开垦土壤,仅为对照样地的16.37%～28.40%（P<0.05）,土壤铵态氮和亚硝态氮含量随着连作年限的增加逐渐达到动态平衡。（2）连作初期会降低土壤硝化和反硝化速率,连作10 a旱区棉田土壤硝化率和反硝化率均降到最低（分别为23.62±1.45 μg·kg^-1·h^-1和5.673±4.632 μg·kg^-1·h^-1）,至连作后期显著增加。（3）土壤pH值对土壤硝化速率和反硝化速率的影响最大（总效应分别为0.5310和0.6516）,土壤硝化率和反硝化率分别在土壤pH值达到阈值范围（8.37和8.01）时达到最大值（91.333 μg·kg^-1·h^-1）和最小值（19.271 μg·kg^-1·h^-1）;土壤水分是影响反硝化作用的第二重要因子。     

干旱区盐碱地覆膜滴灌条件下土壤基质势对糯玉米生长和灌溉水利用效率的影响

利用埋在滴头正下方0．2m深度的真空表负压计,通过控制土壤基质势下限（-5,-10,-15,-20,-25kPa）,研究盐碱地覆膜滴灌条件下土壤基质势对糯玉米（中糯1号）的生长、产量形成过程和灌溉水利用效率的影响。2005和2006年的试验结果表明：糯玉米的株高、茎粗、叶面积指数、地上部分干物质积累量、叶绿素含量等都随着土壤基质势的升高而增加,土壤基质势越高,糯玉米鲜食果穗产量越高,果穗性状也越好;土壤基质势在-5kPa时,糯玉米产量最高;土壤基质势在-10～-15kPa时,灌溉水利用效率最高。     

陕西省眉县猕猴桃园土壤碳氮磷生态化学计量学特征

以眉县猕猴桃园土壤为研究对象,对土壤pH值、含水率、有机碳(SOC)、总氮(TN)、总磷(TP)的分布及其生态化学计量学特征进行研究。结果表明:研究区域猕猴桃园土壤含水率、pH值、SOC、TN和TP含量均存在显著性差异,分别处于1.12%~3.46%、7.12~8.40、4.22~13.90 g·kg~(-1)、0.77~1.84 g·kg~(-1)和0.73~2.45 g·kg~(-1)之间,均值分别为2.73%、7.83、7.66 g·kg~(-1)、1.20 g·kg~(-1)和1.40 g·kg~(-1),其表现C、N元素相对匮乏,而P元素相对丰富;其次,不同区域及不同品种园区土壤中C、N和P的生态化学计量学特征均存在显著性差异,C/N、C/P和N/P的变异系数分别为28.30%、35.71%和21.15%,变化范围分别为3.06~11.99、2.68~10.90和0.48~1.41,均值分别为6.57、5.91和0.90,均低于全国平均水平;相关分析表明,在0.05水平上,pH值与C/P呈显著正相关性;在0.01水平上,pH值与TN、pH值与TP、TN与C/N、TN与C/P、TP与C/N、TP与C/P、TP与N/P呈显著的负相关性,pH值与C/N、SOC与C/N、SOC与C/P、TN与TP、C/N与C/P及C/P与N/P呈显著正相关性。