南亚热带典型地区农业土壤中多环芳烃和有机氯农药研究

参考美国EPA标准方法对南亚热带潮汕地区农业土壤中持久性有机污染物多环芳烃（PAHs）和有机氯农药（OCPs）进行分析,并对其分布和来源进行研究,最后探讨了不同种植方式下污染物的污染特征。结果表明：该区农业土壤中PAHs含量范围从22．1ng／g到1256．9ng／g,与其它地区的污染程度和一些土壤环境质量标准相比,该区处于中等污染水平。高温裂解是土壤PAHs的主要来源。OCPs在被禁止20a后在土壤中仍有残留,残留水平从4．6ng／g到1021．5ng／g,其中HCHs和DDTs的残留未超过国家土壤环境质量标准。早期使用残留是其主要污染源,但新近仍有DDT和硫丹的输入。PAHs和OCPs的污染主要集中在土壤表层和亚表层,且随着深度的加深,污染逐渐减少,但40cm以下,污染变化很小。菜地土壤PAHs污染水平低于稻田土壤,而OCPs污染水平高于稻田土壤。     

鼎湖山退化马尾松林、混交林和季风常绿阔叶林土壤全磷和有效磷的比较

土壤全磷和有效磷浓度的变化随林型和季节不同而异,总的来说,其大小顺序为:季风常绿阔叶林> 混交林>马尾松林(林型);夏季>冬季>春季>秋季(季节),有效磷浓度为:秋季>春季>冬季>夏季(季 节)。收割林下层和凋落物这种人为干扰活动对土壤全磷含量的影响不明显,但对土壤有效磷含量具有显著 的影响。在试验开始时(1990年5月),土壤全磷和有效磷浓度在马尾松林保护样地(停止人为干扰)和处理样 地(按当地习惯继续收割林下层和凋落物)间的差异均不显著。经七年多的试验后,土壤全磷浓度在保护样地 和处理样地间仍十分相似,但土壤有效磷浓度在保护样地显著高于处理样地,说明保护样地在停止人为干扰 后相对于继续受干扰的处理样地其林地条件得到了改善,从而使土壤有效磷含量也得到提高。只要停止人为 干扰,鼎湖山退化马尾松林土壤有效磷供应力是可以自然恢复到季风常绿阔叶林的水平。     

Phosphorus in agricultural soils: drivers of its distribution at the global scale

Phosphorus (P) availability in soils limits crop yields in many regions of the World, while excess of soil P triggers aquatic eutrophication in other regions. Numerous processes drive the global spatial distribution of P in agricultural soils, but their relative roles remain unclear. Here, we combined several global data sets describing these drivers with a soil P dynamics model to simulate the distribution of P in agricultural soils and to assess the contributions of the different drivers at the global scale. We analysed both the labile inorganic P (P_ILAB), a proxy of the pool involved in plant nutrition and the total soil P (P_TOT). We found that the soil biogeochemical background corresponding to P inherited from natural soils at the conversion to agriculture (BIOG) and farming practices (FARM) were the main drivers of the spatial variability in cropland soil P content but that their contribution varied between P_TOT vs. P_ILAB. When the spatial variability was computed between grid cells at half‐degree resolution, we found that almost all of the P_TOT spatial variability could be explained by BIOG, while BIOG and FARM explained 38% and 63% of P_ILAB spatial variability, respectively. Our work also showed that the driver contribution was sensitive to the spatial scale characterizing the variability (grid cell vs. continent) and to the region of interest (global vs. tropics for instance). In particular, the heterogeneity of farming practices between continents was large enough to make FARM contribute to the variability in P_TOT at that scale. We thus demonstrated how the different drivers were combined to explain the global distribution of agricultural soil P. Our study is also a promising approach to investigate the potential effect of P as a limiting factor for agroecosystems at the global scale.     

Spatial distribution and risk assessment of copper in agricultural soils,China

High Cu contamination in agricultural soil can cause toxicity, leading to ecological damages. Thus, we need to understand the concentration level, contaminated area, and spatial distribution of Cu in agricultural soils on a regional or national scale. This paper reviewed the studies on Cu concentrations throughout Chinese agricultural soils, based on relevant 482 published papers from 2004 to 2017. The results showed that the average Cu concentration was 29.85 mg/kg, higher than its background of 22.60 mg/kg, indicating that Cu has been introduced into soil from exterior sources. A large high spatial cluster was observed in southern China, including Hunan, Fujian, Guangdong, and Guangxi provinces, while low spatial clusters were mainly found in Chongqing and Shandong provinces. About 3.08% of the agricultural areas faced a high Cu risk, higher than the pollution rates of the whole land uses, based on the spatial distribution of Cu concentrations throughout China. The remaining areas were within the ranges of moderate and low Cu risks.     

几种农田土壤中古菌、泉古菌和细菌的数量分布特征

真核生物、细菌和古菌三者共同构成了生命的三域系统.古菌作为第3种生命形式,不仅能在高温、强酸和高盐等极端环境下生存,而且在海洋、湖泊和土壤等生境中也广泛分布,预示其在整个生态系统中有着不可估量的作用.本文以2个农田剖面土壤和2个长期施肥试验站祁阳(QY)和封丘(FQ)的土壤为对象,以实时定量PCR方法为主要研究手段,对土壤中古菌(包括泉古菌)和细菌的16S rRNA基因拷贝数丰度变化进行了研究.结果表明:土壤泉古菌16S rRNA基因拷贝数要低于古菌l～2个数量级,两者与细菌相比,16S rRNA基因拷贝数大小顺序为土壤泉古菌＜古茵＜细菌,而古菌和泉古菌16S rRNA基因拷贝数与细菌的比值均随土壤深度加深而增大.不同施肥处理对土壤古菌和泉古茵的数量有显著影响.QY试验站土壤古菌和细菌的数量与土壤pH值显著相关(分别为r=0.850,P＜0.01和r=0.676,P＜0.05).FQ古菌、泉古菌和细菌与土壤pH值相关性不显著,与土壤有机质含量相关性均达显著水平(分别为r=0.783,P＜0.05;r=0.827,P＜0.05;r=0.767,P＜0.05).了解古菌包括泉古菌在农田土壤中的分布,可为评价其在生态系统和物质循环中的作用提供重要的理论依据.     

Pollution assessment of organochlorine pesticides in urban agricultural soils of Jilin City,China

The content, source, and pollution level of organochlorine pesticides (OCPs) in soils are necessary to assess potential risks to eco-environment and human health, and to target environment-friendly policies. A total of 50 surface soil samples were collected from urban vegetable fields of Jilin City and thirteen OCPs were analyzed. The concentrations were in the ranges of 3.16–48.35 ng·g^?1 for Dichloro-Diphenyl-Tricgloroethanes (DDTs, sum of o, p′-DDT, p, p′-DDT, p, p′-DDD, and p, p′-DDE), 4.37–44.77 ng·g^?1 for Hexachlorocyclohexanes (HCHs, sum of α-HCH, β-HCH, γ-HCH, and δ-HCH), 1.19–13.17 ng·g^?1 for Chlordanes (sum of heptachlor, t-chlordane, and c-chlordane), 0.24–2.60 ng·g^?1 for aldrin, and nd–3.43 ng·g^?1 for dieldrin, respectively. The different compositions indicated that the residues of DDTs and HCHs originated mainly from the historical application, while chlordanes were mostly from recent input. On the basis of soil quality standards of China and the Netherlands, DDTs and chlordanes in this study were categorized as light pollution, and HCHs were classified as no pollution for the majority of soil samples. There are a variety of OCPs residues in urban vegetable soils of Jilin City, but it is still safe and suitable for agricultural production.     

Biodegradation of atrazine in surface soils and subsurface sediments collected from an agricultural research farm

The purpose of the present study was to assess atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) mineralization by indigenous microbial communities and to investigate constraints associated with atrazine biodegradation in environmental samples collected from surface soil and subsurface zones at an agricultural site in Ohio. Atrazine mineralization in soil and sediment samples was monitored as ¹⁴CO₂ evolution in biometers which were amended with ¹⁴C-labeled atrazine. Variables of interest were the position of the label ([U-¹⁴C-ring]-atrazine and [2-¹⁴C-ethyl]-atrazine), incubation temperature (25°C and 10°C), inoculation with a previously characterized atrazine-mineralizing bacterial isolate (M91-3), and the effect of sterilization prior to inoculation. In uninoculated biometers, mineralization rate constants declined with increasing sample depth. First-order mineralization rate constants were somewhat lower for [2-¹⁴C-ethyl]-atrazine when compared to those of [U-¹⁴C-ring]-atrazine. Moreover, the total amount of ¹⁴CO₂ released was less with [2-¹⁴C-ethyl]-atrazine. Mineralization at 10°C was slow and linear. In inoculated biometers, less ¹⁴CO₂ was released in [2-¹⁴C-ethyl]-atrazine experiments as compared with [U-¹⁴C-ring]-atrazine probably as a result of assimilatory incorporation of ¹⁴C into biomass. The mineralization rate constants (k) and overall extents of mineralization (P _max ) were higher in biometers that were not sterilized prior to inoculation, suggesting that the native microbial populations in the sediments were contributing to the overall release of ¹⁴CO₂ from [U-¹⁴C-ring]-atrazine and [2-¹⁴C-ethyl]-atrazine. A positive correlation between k and aqueous phase atrazine concentrations (C _eq ) in the biometers was observed at 25°C, suggesting that sorption of atrazine influenced mineralization rates. The sorption effect on atrazine mineralization was greatly diminished at 10°C. It was concluded that sorption can limit biodegradation rates of weakly-sorbing solutes at high solid-to-solution ratios and at ambient surface temperatures if an active degrading population is present. Under vadose zone and subsurface aquifer conditions, however, low temperatures and the lack of degrading organisms are likely to be primary factors limiting the biodegradation of atrazine.     

Biodegradation of atrazine in surface soils and subsurface sediments collected from an agricultural research farm

The purpose of the present study was to assess atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) mineralization by indigenous microbial communities and to investigate constraints associated with atrazine biodegradation in environmental samples collected from surface soil and subsurface zones at an agricultural site in Ohio. Atrazine mineralization in soil and sediment samples was monitored as ¹⁴CO₂ evolution in biometers which were amended with ¹⁴C-labeled atrazine. Variables of interest were the position of the label ([U-¹⁴C-ring]-atrazine and [2-¹⁴C-ethyl]-atrazine), incubation temperature (25°C and 10°C), inoculation with a previously characterized atrazine-mineralizing bacterial isolate (M91-3), and the effect of sterilization prior to inoculation. In uninoculated biometers, mineralization rate constants declined with increasing sample depth. First-order mineralization rate constants were somewhat lower for [2-¹⁴C-ethyl]-atrazine when compared to those of [U-¹⁴C-ring]-atrazine. Moreover, the total amount of ¹⁴CO₂ released was less with [2-¹⁴C-ethyl]-atrazine. Mineralization at 10°C was slow and linear. In inoculated biometers, less ¹⁴CO₂ was released in [2-¹⁴C-ethyl]-atrazine experiments as compared with [U-¹⁴C-ring]-atrazine probably as a result of assimilatory incorporation of ¹⁴C into biomass. The mineralization rate constants (k) and overall extents of mineralization (P _max ) were higher in biometers that were not sterilized prior to inoculation, suggesting that the native microbial populations in the sediments were contributing to the overall release of ¹⁴CO₂ from [U-¹⁴C-ring]-atrazine and [2-¹⁴C-ethyl]-atrazine. A positive correlation between k and aqueous phase atrazine concentrations (C _eq ) in the biometers was observed at 25°C, suggesting that sorption of atrazine influenced mineralization rates. The sorption effect on atrazine mineralization was greatly diminished at 10°C. It was concluded that sorption can limit biodegradation rates of weakly-sorbing solutes at high solid-to-solution ratios and at ambient surface temperatures if an active degrading population is present. Under vadose zone and subsurface aquifer conditions, however, low temperatures and the lack of degrading organisms are likely to be primary factors limiting the biodegradation of atrazine.Abbreviations C _eq solution phase atrazine concentration at equilibrium - C _s amount of atrazine sorbed - CLA [2-¹⁴C-ethyl]-atrazine - k first-order mineralization rate constant - K _d sorption coefficient - m slope - P _max maximum amount of CO₂ released - RLA [U-¹⁴C-ring]-atrazine     

农田土壤中磷素有效性及影响因素

土壤中磷的有效性直接决定着农田生产力. 基于分布于我国不同气候区长期定位施肥试验,总结了不同农田土壤的磷素含量、有效性及转化的影响因素.结果表明： 目前我国不同类型的土壤中全磷含量在0.31～1.72 g·kg^-1,速效磷含量在0.1～228.8 mg·kg^-1.土壤母质、理化性质和施肥方式是影响农田土壤磷素有效性的主要因素,未来应注重有机肥和化肥的混合施用以提高农田土壤磷素有效性,并关注可能导致的环境影响.     

中国盐碱土壤中AM菌的生态分布

对我国盐碱土壤中丛枝菌根（Ａｒｂｕｓｃｕｌａｒ Ｍｙｃｏｒｒｈｉｚａ,ＡＭ） 菌的种属构成、生态分布状况进行了研究．结果表明,不同地区ＡＭ 菌种属构成不同,其种属组成、分布与土壤类型、碱化度和土壤有机质含量有关．盐渍化砂土、壤土和粘土中,Ｇｌｏｍｕｓ 属的真菌数量最多,Ａｃａｕｌｏｓｐｏｒａ 属次之,而Ｇｌｏｍｕｓ 属中的Ｇ．ｍｏｓｓｅａｅ 则是分布最为广泛的菌种．随土壤碱化度的增加,Ｇｌｏｍｕｓ ｍｏｓｓｅａｅ 出现频率随之相对增加．在一定范围内有机质含量越高,土壤中ＡＭ 菌种和属的种类就越多．ＡＭ 菌的种属组成因不同寄主植物而异,其中豆科植物根围中ＡＭ 菌分布的种属数量最多．     

贵州兴仁煤矿区农田土壤重金属化学形态及风险评估

为了解煤矿区周边农田土壤重金属污染状况,采集了贵州省兴仁县某典型煤矿区农田土壤样品64份,测定了土样中重金属(As、Cr、Pb、Zn、Cd、Hg、Cu、Ni)总量及各形态含量,采用单因子指数法、潜在生态风险指数法(Hkanson法)和风险评估编码法(RAC)对研究区主要土壤利用类型(水稻土、薏米地、植烟土和菜园土)中重金属进行潜在生态风险评估和环境风险评价.结果表明： 不同利用类型土壤中重金属含量除Zn外,其他元素均明显超过贵州省背景值.单因子指数法评价结果表明,As、Pb、Hg和Cu污染较为严重,均属重度污染.形态分析表明,土壤中重金属形态构成差异明显,酸可提取态As、酸可提取态Cd所占比例较高;Cr、Zn、Cu、Ni主要以残渣态为主;Pb主要以可还原态和残渣态为主;而Hg的酸可提取态、可还原态、可氧化态均占有相当比例,三者之和大于55%.重金属可利用度大小顺序为:As(63.6%)>Hg(57.3%)>Cd(56.4%)>Pb(52.5%)>Cu(45.7%)>Zn(32.8%)>Ni(26.2%)>Cr(13.2%).潜在生态风险指数表明,各类型土壤潜在生态风险(RI)〖JP2〗为:菜园土(505.19)>薏米地(486.06)>植烟土(475.33)>水稻土(446.86),均处于较高风险.风险评估编码法结果显示,As在水稻土、薏米地及植烟土中均处于高风险,在菜园土中处于中等风险;Cd、Hg均处于中等风险,Cr、Pb、Zn、Cu和Ni均处于低风险.因此,对该区域农田土壤进行管控时应重点考虑As、Cd和Hg污染.     

Distinctive Mesorhizobium populations associated with Cicer arietinum L. in alkaline soils of Xinjiang, China

Background and aims

Rhizobia associated with chickpea in the main chickpea production zone of Xinjiang, China have never been investigated. Here, we present the first systematic investigation of these rhizobia’s genetic diversity and symbiotic interactions with their host plant.

Methods

Ninety-five isolates obtained from chickpea nodules in eight alkaline-saline (pH?8.24–8.45) sites in Xinjiang were characterized by nodulation test, symbiotic gene analysis, PCR-based restriction fragment length polymorphism (RFLP) of the 16S rRNA gene and 16S–23S rRNA intergenic spacer (IGS), BOX-PCR, phylogenies of 16S rRNA and housekeeping genes (atpD, recA and glnII), multilocus sequence analysis (MLSA) and DNA–DNA hybridization.

Results

All 95 isolates were identified within the genus of Mesorhizobium. Similarities less than 96.5% in MLSA and DNA–DNA hybridization values (<50%) between the new isolates and the defined Mesorhizobium species, and high similarities (>98%) of symbiotic genes (nodC and nifH) with those of the well studied chickpea microsymbioints Mesorhizobium ciceri and Mesorhizobium mediterraneum were found.

Conclusions

Chickpea rhizobia in alkaline-saline soils of Xinjiang, China, form a population distinct from the defined Mesorhizobium species. All these chickpea rhizobia in Xinjiang harbored symbiotic genes highly similar to the type strains of two well-studied chickpea rhizobia, M. ciceri and M. mediterraneum, evidencing the possible lateral transfer of symbiotic genes among these different rhizobial species. On the other hand, chickpea may strongly select rhizobia with a unique symbiotic gene background.     

Phosphorus fractions and alkaline phosphatase activity in sediments of a large eutrophic Chinese lake (Lake Taihu)

Spatial, vertical, and seasonal variations in phosphorus fractions and in alkaline phosphatase activity (APA) were investigated in sediments in a large-shallow eutrophic Chinese lake (Lake Taihu) in 2003–2004. The phosphorus content was highest in the most seriously polluted lake area. Iron-bound phosphorus (Fe(OOH)～P) dominated (47% on average) among the phosphorus fractions determined according to Golterman (Hydrobiologia 335:87–95, 1996). Notably, organically-bound P comprised a further significant additional portion (acid-soluble + hot NaOH-extractable organic P = 25%), which was highest at the most polluted sites. The Fe(OOH)～P content was the lowest in spring (April, 2004), suggesting that degradation of organic matter led to the release of iron-bound phosphates. Sediment APA showed a significant positive relationship with both organically-bound P and Fe(OOH)～P. Consequently, organically-bound P is an important portion of the sediment phosphorus in Lake Taihu. It is mainly derived from freshly-settled autochthonous particles and from external discharges. Organically-bound P induces APA and may lead to the release of bioavailable phosphates from the organic sediments, thereby accelerating lake eutrophication.     

衡阳紫色土丘陵坡地植被恢复阶段土壤特性的演变

采用空间代替时间序列方法,对衡阳紫色土丘陵坡地不同恢复阶段的土壤理化性质、土壤微生物数量、土壤微生物学性质和主要酶活性特征以及它们之间的相互关系进行研究。结果表明:不同恢复阶段土壤理化特征存在明显差异,从狗尾草群落阶段(Ⅰ)、紫薇-狗尾草群落阶段(Ⅱ)、牡荆+剌槐群落阶段(Ⅲ)到枫香+苦楝-牡荆群落阶段(Ⅳ),0—40cm土壤含水量、容重、非毛管孔隙度、孔隙比、大于0.25mm水稳性团聚体含量、有机碳(SOC)、全氮(TN)、碱解氮(AN)与速效磷(AP)显著增加,土壤容重显著减小,土壤pH值逐渐减小,土壤全磷(TP)、全钾(TK)与速效钾(AK)其差异变化不大,土壤理化特征的差异引起土壤微生物数量、微生物学性质与土壤酶活性的变化;不同恢复阶段土壤微生物总数显著增加,其中细菌数量显著增加,而真菌与放线菌数量显著减少;不同恢复阶段土壤基础呼吸(SBR)、土壤微生物量碳(SMBC)、土壤微生物量氮(SMBN)、土壤微生物量磷(SMBP)、土壤微生物熵(Cmic/Corg)显著增加,而代谢熵或呼吸熵(qCO2)显著减小,碳氮比(C/N)逐渐减小;不同恢复阶段均显著地增加了脲酶(URE)、蔗糖酶(INV)与磷酸酶(APE)的活性;土壤理化性状、土壤微生物数量、土壤微生物学性质与土壤酶活性之间存在密切的相关性。     

Phosphorus mobility in sediments of acid mining lakes,Lusatia, Germany

Changes in benthic retention and mobility of P were studied in a chronosequential approach in acid (pH 2.5–3.5) to moderately acid (pH 5.6–6.8) mining lakes (MLs) with respect to the threat of eutrophication during maturation. Although various MLs exhibit a high pelagic P availability there is currently no distinct threat of an enhanced eutrophication due to a C limitation and a high benthic P immobilization potential. The sequential P extraction applied revealed an increase in sedimentary total P with increasing pH due to the additional uptake of P by Al- and Fe-hydroxides, but no increase in mobile P forms. Currently, the excess in reactive Fe at a high Fe:P ratio in surface sediment at pH ∼3 favours an efficient P precipitation of Fe-oxi-hydroxides with a high specific surface area for P adsorption. However, an enhanced future P mobility of ML sediments and a threat of eutrophication results from: (1) a distinct reduction of the import of Fe and Al from the catchment over time, resulting in a lower supply towards the sediments, and (2) a reduction in the sedimentary Fe mineral surface area due to the future rise in pH.     

Comparison of methods to investigate microbial populations in soils under different agricultural management

As water is a source of nosocomial infections in hospitals, the presence of fastidious Gram-negative bacteria in water samples taken in a university hospital was investigated. Water samples were inoculated onto agar plates and into amoebal microplates for co-culture. Sixty-eight alpha proteobacteria isolates were obtained and characterized using phenotypic methods and 16S rRNA gene sequence comparison. The latter approach divided the strains into seven clusters. Of these, one corresponded to previously recognized Afipia felis and it is likely that six were closely related new species. As these bacteria are fastidious and can not be cultivated on standard microbiological media, their possible role in hospital-acquired human infections should be investigated.     

不同农业利用方式下土壤铜和锌的累积

通过对山东寿光表层农业土壤(0～20cm)铜和锌的调查研究,了解不同农业利用方式下土壤铜和锌含量的差异,揭示其空间分布规律及其累积特征.从研究区域采集来自设施菜地、露天菜地、小麦/玉米/棉花地和自然土壤等4类当地主要农业利用方式的土壤(n=127),样点覆盖寿光整个农业生产区域.结果表明,山东寿光农业土壤的铜含量均值为26.43mg · kg-1,极差69.11 mg · kg-1,锌含量均值为80.50mg · kg-1,极差210.8 mg · kg-1.不同农业利用方式的土壤铜锌含量从高至低的顺序均为:设施菜地>露天菜地>小麦/玉米/棉花地>自然土壤,不同农业土壤铜锌含量均出现了明显累积趋势,其中,以设施菜地的累积问题最为突出,其铜锌含量分别为33.91、124.2mg · kg-1,显著高于其它农业利用土壤类型, 但均未超过国家土壤环境质量II级标准;从研究区域铜锌含量的空间分布看,当地农业土壤铜锌含量均表现为北部、南部区域较低、中部地带较高的趋势;在集约化种植模式下,设施菜地铜锌含量随着设施年限的延长显著增加(p<0.05),其累积速率分别为1.49mg · kg-1 · a-1和2.59mg · kg-1 · a-1,这可能与铜锌含量相对较高的有机肥大量施用有关.     

Phosphorus retention as a function of external loading,hydraulic turnover time,area and relative depth in 54 lakes and reservoirs

We analysed phosphorus retention as a function of external loading, hydraulic turnover time, area and relative depth on the basis of published data from 54 lakes and reservoirs in different climate regions around the world. Our analysis demonstrated that reservoirs and lakes that received higher areal loading of phosphorus (TP_in) also retained more P per m² but the proportion of the external P loading retained in the waterbody (retention coefficient, R _P) remained generally independent of TP_in. The waterbodies with longer hydraulic residence times (T _R) retained larger proportions of external P and the correlation between R _P and T _R was much stronger in lakes with areas larger than 25 km² than in the whole data set. TP_in and T _R together determined 78% of the variation in R _P in large lakes. We also partially confirmed our hypothesis that waterbodies with bigger relative depths (Z _R) retain more of the external phosphorus than larger and shallower waterbodies with lower Z _R. The hypothesis was, however, validated only for lakes larger than 25 km² and for those with T _R <0.3 year, where R _P increased significantly with increasing Z _R. In stratified lakes, increasing relative depth correlated with reduced P retention capacity, demonstrating the complex nature of phosphorus biogeochemistry in lake ecosystems.     

Source apportionment and health risk assessment of heavy metals in agricultural soils in Xinglonggang,Northeastern China

Heavy metals in soil can affect human health through the exposure pathways of oral ingestion, dermal contact, and inhalation. In this study, to assess the health risk of heavy metals in the agricultural area of Xinglonggang, 52 soil samples were collected and tested to obtain the concentrations of As, Cd, Cr, Cu, Ni, Pb, V, and Zn in the soil. The enrichment factor indicated that the heavy metals of the agricultural soils were enriched, but the degree of enrichment was mild for all of the heavy metals. Coefficient analysis and principal component analysis indicated that V, Cr, Ni, and Pb were mainly from natural sources, As was from irrigation, Cu and Cd tended to be from chemical fertilizers and pesticides, and Zn was from mixed sources including irrigation, chemical fertilizers, and pesticides. A human-health risk assessment indicated that the residents in the study area face high risk from carcinogens and low risk from noncarcinogens; As and Cr are the major heavy metals affecting human health. This study provides a reference and a basis for formulating effective measures to prevent and control heavy metal enrichment in agricultural soils.