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1.
目的 调查靖安县社区居民糖尿病患病现状,探讨其影响因素,为开展糖尿病综合防治提供依据.方法 采用PPS法和分层整群抽样法确定调查对象,从村委会户籍登记簿中按生日接近法抽取2012年江西省靖安县辖区内≥18岁居民2 868人,采用χ2检验、t检验及多因素非条件Logistic回归分析对糖尿病影响因素进行分析.结果 靖安县18岁以上社区居民糖尿病患病率为7.3%(210/2 868).多因素非条件Logistic逐步回归分析结果显示,年龄大(OR=1.024)、已婚或同居(OR=0.519)、城镇职工医保(OR=0.370)、月人均收入低(OR=0.848)、有糖尿病家族史(OR=3.779)、近1年有感觉紧张(OR=0.641)、口味重(OR=0.740)、健康体检次数少(OR=0.794)、健身活动量少(OR=0.917)、BMI高(OR=1.328)、文化程度低(OR=1.186)及每天睡眠时间少(OR=0.855)为糖尿病的危险因素.结论 靖安县社区居民糖尿病患病率已经处于较高水平.应采取综合措施,更应控制各种危险因素,就可预防和控制糖尿病的发生、发展.  相似文献   

2.
Effects of copper-smelter-related deposition of heavy metals in the soil on carbohydrate metabolism of fine roots of the native European black poplar were investigated in spring and autumn. Total soluble non-structural carbohydrates in fine roots from trees growing in the polluted habitat were lower than in a control site, but this was directly associated only with a lower raffinose concentration. Neither glucose nor fructose concentrations differed significantly between polluted and unpolluted sites. In contrast, the galactose concentration was higher in the presence of heavy metals, especially in autumn. Also the stachyose concentration was higher in the polluted site, but only in autumn, suggesting it could be an alternative way of detoxification of galactose. No difference between control and polluted stands was observed in sucrose concentration. However, estimates of sucrolytic activity revealed markedly higher activities of sucrose synthase (SuSy), soluble acid (AI) and neutral (NI) invertases in the polluted stand than in the control. In contrast, the estimated glycolytic enzyme activities were not affected by the presence of heavy metals in soil.  相似文献   

3.
The evolution of total N, total oxidizable C, water-soluble NH(4)(+)-N, exchangeable NH(4)(+)-N and soluble NO(3)(-)-N was studied in Canarian volcanic soils under mountainous legume scrub affected by a wildfire by June 2003. Three systematic soil samplings in the burned area and in neighbouring non-burned sampling points were carried out 3, 7 and 12 months after the fire event. The results showed an important mobilization of N (as total N and soluble and exchangeable NH(4)(+)-N) in the soil within the burned area at short term, with a simultaneous depletion of nitrates. Later on, the water-soluble NH(4)(+)-N levels remained nearly constant along the study period in the burned area, whereas the exchangeable NH(4)(+) decreased progressively. Nitrates were found to increase inside and outside the burned area, but the increase rate was much higher for the burned samples. Total N fluctuated along the year, although its levels were generally higher in the burned area. However, such a response pattern of N to fire in this environment was insufficient to prompt the recovery of the plant cover.  相似文献   

4.
The disposal of animal manures, wastewater and sewage sludge to agricultural land can lead to the transfer of steroid hormones like 17beta-estradiol and testosterone into soils, surface and groundwaters. The objective of this study was to investigate the effects of different site histories like wastewater irrigation and sewage sludge application on hormone mineralization and sorption in soils. Two agricultural sites with different long-term treatment histories with wastewater and sewage sludge were sampled. The mineralization of (14)C-17beta-estradiol and (14)C-testosterone was studied during incubations at 20 degrees C over three weeks. Despite the structural resemblance of both hormones the mineralization rate of 17beta-estradiol was about an order of magnitude lower than that of testosterone in all four soils, reaching 5-7% vs. 50-59%, respectively. Estradiol mineralization was significantly lower in soils with long-term wastewater irrigation than in the corresponding soil with freshwater irrigation. Pre-incubation of the soils with unlabeled hormones or application of the hormones within a wastewater matrix had only minor effects on their mineralization. The results indicate that estradiol mineralization occurs co-metabolically and is limited by sorption, whereas testosterone appears to be utilized directly by soil microorganisms. Sorption of (14)C-17beta-estradiol and (14)C-testosterone to sterile and unsterile soils was determined in batch experiments with CaCl(2) or wastewater solution with hormone concentrations of 0.13-0.0013 mug mg(-1). FREUNDLICH sorption isotherms and parameters like K(F) and log K(oc) values were used to describe the results. The K(F) values for estradiol sorption were generally about 1.2 to 1.6-fold higher than for testosterone. The SOC-normalized partition coefficients K(oc) also differ accordingly and indicate quite large differences in soil organic matter qualities relating to hormone sorption between the soils and treatments. When the hormones were added to the soil within a wastewater matrix less estradiol was sorbed in the solid phase than in the controls with pure water, thus indicating that wastewater contains soluble sorbents.  相似文献   

5.
采用大型恒刚度直剪仪,系统研究超孔隙水压力对黏性土中桩土界面剪切性能的影响。根据制定的测试超孔隙水压力方案,对4个粗糙度等级(混凝土表面锯齿状峰谷距为0、2、4、6mm)的不同含水率黏性土中桩土界面在不同剪切速率下进行剪切试验。针对界面粗糙度、黏性土含水率、剪切速率3个变化参数对界面抗剪强度的影响进行分析。结果表明:界面粗糙度越大,界面超孔隙水压力越小,有效法向应力越大,黏性土颗粒与混凝土表面吸附性越大,桩土界面抗剪强度越大;黏性土含水率越大,界面超孔隙水压力越大,有效法向应力越小,黏性土颗粒与混凝土表面吸附性不能完全发挥,桩土界面抗剪强度反而减小;在剪切速率0.4~1.0mm/min范围内,剪切速率越大,界面超孔隙水压力增幅较小,有效法向应力变化不大,桩土界面抗剪强度虽有减小,但不同剪切速率下超孔隙水压力对桩土界面抗剪强度的影响不明显。  相似文献   

6.
The mobility and bioavailability of lead (Pb) in soils can be mitigated by its immobilization using both soluble and insoluble phosphate (P) compounds. The effectiveness of insoluble P sources on Pb immobilization depends on their rate of dissolution which can be enhanced by phosphate solubilizing bacteria (PSB). In this study, the effect of soluble (potassium dihydrogen phosphate) and insoluble (rock phosphate in the presence and absence of PSB) P compounds on the immobilization of Pb, and leaching of Pb and P was examined using both naturally contaminated (SR soil: NH4NO3 extractable Pb: 28.7 mg/kg, pH: 5.88, organic matter: 0.7%) and Pb spiked (AH soil: NH4NO3 extractable Pb: 42.7 mg/kg, pH: 5.23, organic matter: 10.9%) soils. Phosphate compounds were added at the rate of 200 mg P/kg and 800 mg P/kg for SR and AH soils, respectively. Soluble P treatment immobilized 80% and 57% of Pb in SR and AH soils, respectively. Insoluble rock phosphate immobilized 40% and 9% of Pb without PSB, and 60% and 17% with PSB in SR and AH soils, respectively. Lead leaching was the lowest when soils were amended with rock phosphate in the presence of PSB, which reduced Pb leaching by 36% for SR soil and 18% for AH soil compared to the control. The leaching of Pb increased when the soils were amended with soluble P because soluble P treatment increased dissolved organic carbon (DOC) concentration of soil, thereby increasing Pb mobility. Soluble P treatment significantly increased P leaching and 9% of total added P was leached from low P retaining AH soil. The optimum level of P amendment is a critical issue when soluble P is used as a Pb immobilizing agent because of eutrophication resulting from excessive P leaching to surface and ground water. While the soluble P compound was effective in the immobilization of Pb, it resulted in P leaching which increased with increasing levels of P addition. However, rock phosphate amendment with PSB achieved the immobilization of Pb with a minimum effect on both Pb and P leaching.  相似文献   

7.
The reduced availability of water resources in semi-arid Mediterranean regions requires an efficient use of supply sources. Urban wastewater, after treatment to minimise health hazards, may constitute an important resource for irrigation in areas characterised by intensive agriculture. These considerations have motivated an investigation (during the irrigation season 1996) of the dynamics of microbial biomass in the soil of a citrus orchard in eastern Sicily, which has been irrigated for 15 years with lagooned urban wastewater, to evaluate the effects of this practice on soil fertility. The analyses of parameters regarding soil microbial biomass (microbial carbon and microbial nitrogen, soluble carbon and nitrogen, cumulative respiration, respiratory quotient and enzymatic activity in the soil) have confirmed that the evolution of soil microflora is directly conditioned by the type of water used for irrigation and climatic conditions. Just before the beginning of the irrigation season (May), microbial biomass carbon (MBC), soluble C, cumulative respiration and enzymatic activity were significantly higher in the soil irrigated with wastewater with respect to the same soil irrigated with 'clear' water; the qCO2 was significantly lower. In June, after 1 month of irrigation, both soils showed an increase of all microbial parameters except for enzymatic activity and qCO2 which showed a significant reduction. In September, at the end of the irrigation period, there was a decrease of almost all investigated parameters in both plots, which was more evident in the soil irrigated with 'clear' water. The microbial biomass of the soil irrigated with wastewater, during the irrigation period, did not undergo any negative effects, having an evolution analogous to the plot irrigated with 'clear' water. The use of lagooned wastewater after three lustrums has shown, particularly in the dry season, an increase in quantity of easily available nutrients, with an improvement of the metabolic efficiency of soil microflora coupled with a more marked activity of total hydrolase and phosphatases. The variations of the parameters related to the soil microflora were strongly influenced by the seasonal climatic trend.  相似文献   

8.
The childhood-related, geographically-linked factor which predisposes towards (or protects against) multiple sclerosis (MS) could be one or more chemicals in the environment. Chemical study of the environment or "focus" of an MS cluster may maximize the chances of detecting such an etiological link. The soil chemistry of an MS focus (Henribourg, Saskatchewan) was compared with North American norms, and with the chemistry of soil from a nearby control area with a near-zero incidence of MS and of childhood homes of MS cases. A combination of our present results with those reported in the literature suggests that an environment predisposing to MS may have a number of the following chemical characteristics: Calcareous; with soils (but not necessarily waters) generally low in copper, iron and vanadium; with excess lead, nickel and zinc in the upper soil layer; with waters relatively high in chloride, chromium, molybdenum, nitrate plus nitrite, and zinc; but low in selenium and sulfate. One possible causal pathway to explain the apparent link between the excess rate of MS and some of the curious geochemical findings at Henribourg is presented. Many other possible explanations could equally well be advanced, and methods for testing such alternative hypotheses are proposed.  相似文献   

9.
In situ soil treatment using phosphoric acid (H(3)PO(4)) may be an effective remedial technology for immobilizing soil Pb and reducing Pb risk to human health and ecosystem. The treatment efficacy of three H(3)PO(4) application methods was assessed in a smelter-contaminated urban soil located in the Jasper County Superfund Site, Missouri. Soil, with an average of 3529 mg Pb kg(-1) and in the 2- by 4-m plot size, was treated with H(3)PO(4) at a rate of 10 g P kg(-1) in four replicates by each of three methods: rototilling; surface application; pressure injection. Three soil cores, 2.5-cm diameter and 30-cm long, were taken from each plot before and 90 days after treatment and analyzed for soluble P, bioaccessible Pb and solid-Pb speciation. Applications of H(3)PO(4) induced the heterogeneity of soluble P in soil, with the highest concentrations in the surface. Three application methods mixed the H(3)PO(4) more effectively in the horizontals than the verticals of treated soil zone. The H(3)PO(4) applications significantly reduced Pb bioaccessibility in the soil, which was influenced by the concentrations of soil soluble P and solid-Pb species. The risk reductions of soil Pb were achieved by formation of pyromorphites or pyromorphite-like minerals. The rototilling appears to be the most effective treatment method in context of the homogeneity of soluble P and the reduction of Pb bioaccessibility in treated soil.  相似文献   

10.
盐害严重影响着土遗址的保存,并诱发一系列的病害,为快速、准确地测定遗址土体中易溶盐的总含量,本研究基于盐溶液导电原理,测试遗址土体中常见的易溶盐及其混合盐电导率与含盐量的关系,采用固定容器和适宜的操作方法,建立电导率与含盐量的关系,将电导率与含盐量关系曲线分为线性区、指数区和参考区,并给出相应区域含盐量的回归方程和测定误差,通过现场试验验证电导率测试法在遗址保护加固工程中水源检测、工程用土选址和遗址盐分测定中的可靠性。研究表明:已知盐分类型和混合比例的条件下,电导率在0~8 ms/cm时,电导率与含盐量具有很好的线性关系,线性相关系数超过0.98;电导率在8~12 ms/cm时,电导率与含盐量表现为指数关系,相关系数超过0.99,电导率大于12 ms/cm时,含盐量变化迅速,可据此得到遗址体含盐量的下限。未知类型的盐渍土,线性区的测试误差低于0.2%的土体含盐量,指数区的测试误差低于0.5%,并在水源、工程用土土源和夯筑墙体易溶盐检测中,取得了很好的效果。该方法具有操作简便、快速测试、微损检测的优点,所测的土体易溶盐含量具有较高的精度,满足实际工程中快速测试评价的要求。  相似文献   

11.
The degradation of DDT [1,1-bis(4-chlorophenyl)-2,2,2-trichloroethane] and DDE [2,2-bis(4-chlorophenyl)-1,1-dichloroethylene] in highly and long-term contaminated soil using Fenton reaction in a slurry system is studied in this work. The influence of the amount of soluble iron added to the slurry versus the mineral iron originally present in the soil, and the influence of H(2)O(2) concentration on the degradation process are evaluated. The main iron mineral species encountered in the soil, hematite (Fe(2)O(3)), did not show catalytic activity in the decomposition of H(2)O(2), resulting in low degradation of DDT (24%) and DDE (4%) after 6 h. The addition of soluble iron (3.0 mmol L(-1)) improves the reaction reaching 53% degradation of DDT and 46% of DDE. The increase in iron concentration from 3.0 to 24 mmol L(-1) improves slightly the degradation rate of the contaminants. However, similar degradation percentages were obtained after 24 h of reaction. It was observed that low concentrations of H(2)O(2) were sufficient to degrade around 50% of the DDT and DDE present in the soil, while higher degradation percentages were achieved only with high amounts of this reagent (1.1 mol L(-1)).  相似文献   

12.
Contribution of microbial activity to virus reduction in saturated soil   总被引:2,自引:0,他引:2  
Nasser AM  Glozman R  Nitzan Y 《Water research》2002,36(10):2589-2595
Application of wastewater to soil may result in the contamination of groundwater and soil with pathogenic microorganisms and other biological and chemical agents. This study was performed to determine the antiviral microbial activity of soil saturated with secondary effluent. Low concentrations (0.05mg/ml) of protease pronase resulted in the inactivation of more than 90% of seeded Cox-A9 virus, whereas Poliovirus type 1, Hepatitis A virus (HAV) and MS2 bacteriophages were found to be insensitive to the enzyme activity. Exposure of Cox A9 virus to P. aeruginosa extracellular enzymes resulted in 99% inactivation of the seeded virus. Hepatitis A virus was found to be as sensitive as the Cox A9 virus, whereas Poliovirus 1 and MS2 were found to be insensitive to P. aeruginosa extracellular enzymatic activity. Furthermore, the time required for 99% reduction (T99) of Cox A9 and MS-2 Bacteriophage, at 15 degrees C, in soil saturated with secondary effluent was found to be 7 and 21 days, respectively. Faster inactivation was observed for MS2 and Cox A9 in soil saturated with secondary effluent incubated at 30 degrees C, T99 of 2 and 0.3 days, respectively. Although the concentration of the total bacterial count in the soil samples increased from 10(3) cfu/g to 10(5) cfu/g after 20 days of incubation at 30 degrees C, the proteolytic activity was below the detection level. The results of this study indicate that the virucidal effect of microbial activity is virus type dependent. Furthermore microbial activity in the soil material can be enhanced by the application of secondary effluent at higher temperature. The results also showed that MS2 bacteriophage can be used to predict viral contamination of soil and groundwater.  相似文献   

13.
Multiple Sclerosis (MS) is one of the most common diseases of the central nervous system. Although the disease has been associated with some genetic and environmental factors, it has neither clear causes nor clear temporality with respect to exposure. The purpose of this study was to explore potential relationships between MS and outdoor air pollutants in GA. This study used cross-sectional data from the member's list of the Multiple Sclerosis Society's GA chapter (MSS-GA), the US Census, and a database of county-level Toxic Release Inventory data (emissions across identified, reporting sources to outdoor air, as a surrogate indicator of potential exposure to a criteria pollutant subject to regulation or to chemical toxicants). The final study population was 9,072,576 people, including 6247 self-reported MS cases from MSS-GA. Cases were stratified by gender and transformed into county-level, self-reported prevalence rates using 2005 US Census estimates. County-level prevalence was displayed using a Geographic Information System. Linear regression was conducted to investigate potential relationships between self-reported MS prevalence rates, census data, and environmental outdoor air pollutant indicators. MS prevalence tended to be clustered within the largest metropolitan statistical area (MSA) in Georgia, around Atlanta (Fulton County). The best predictive models for the MS prevalence in GA included both per capita income and PM-10 for females, but only per capita income only for males. The clustering of prevalence of MS in the largest MSA of Georgia, after controlling for population distribution, suggested that urban attributes may be associated with MS. The results of this study further suggested a potential role of PM-10 in the etiology of MS in females, perhaps due to the influence of PM-10 on systemic immune response and inflammation. Based on this initial exploratory study, we recommend more basic and clinical exposure research to understand environmental influences on MS. In particular, outdoor air pollutants like particles, and attached chemicals and metals, which have other known adverse cardiopulmonary health outcomes and are subject to federal and state regulations, could be examined using routinely collected outdoor air monitoring station data and/or modeling.  相似文献   

14.
Comparison of the structural stability of pasture and cultivated soils   总被引:1,自引:0,他引:1  
The structural properties of two neighbouring soils from the NW of Spain were evaluated in order to elucidate the effect of management on the soil structural quality and soil organic carbon turnover. The two soils were developed on granite under a warm and humid climate, but differed in land use (pasture and cultivation). The pasture soil had more favourable structural properties than the cultivated soil, showing lower bulk density, higher porosity and water retention. Also, the pasture soil showed a higher mean aggregate diameter and aggregate stability against mechanical agitation in water, as well as lower soil loss under simulated rainfall. This increased structural stability of the pasture soil could be attributed to its higher soil organic matter (SOM) content. The effect of soil use and aggregate size on SOM mineralization was also investigated. Laboratory incubation experiments were conducted with 1-5 mm aggregates and disaggregated <1 mm soil. More C-CO(2) was released by SOM mineralization in the pasture soil than in the cultivated soil, thus indicating a higher microbial activity in the pasture soil. The respiratory quotient (C-CO(2)/Corg) was also higher in the pasture soil, which means that SOM in this soil is more accessible to microbial decomposition. Nevertheless no significant differences were observed between organic C mineralization in the disaggregated <1 mm soil and the undisturbed 5-1 mm aggregates. The overall results demonstrate the need to maintain adequate levels of OM by adding organic amendments or adopting lower impact cultivation practices such as reduced tillage.  相似文献   

15.
基于考虑初始含水量、上覆压力、初始干密度影响,研究了膨胀土竖向增湿变形问题,得到了膨胀土膨胀变形的规律,揭示出相同初始含水量时,初始干密度越大膨胀率越大;相同初始干密度时,初始含水量越大膨胀率越小;其他条件相同时上覆压力越大膨胀率越小。文章还总结出考虑初始含水量、上覆压力、初始干密度影响的膨胀率回归方程,提出用有限的试验数据得到任意组合条件的膨胀率计算方法。由此可进一步求得膨胀土地基的膨胀变形量,为工程计算提供可靠的理论依据。  相似文献   

16.
This paper assesses the ecotoxicity of the antibiotic doxycycline in aged spiked pig manure using a multispecies soil system (MS 3) covering plants, earthworms and soil microorganisms. The study reproduced realistic exposure conditions, as well as higher exposure doses covering the uncertainty factors typically employed for covering interspecies variability. MS 3, consisting of columns of natural sieved soil assembled with earthworms and seeds from three plant species, were employed. Pig manure was spiked with doxycycline (75 or 7500 microg/ml), aged for 15 days under aerobic/anaerobic conditions and added on top of the soil columns (120 ml/column, equivalent to 220 kgN/ha). Water and doxycycline free manure were used as negative controls. Doxycycline (7500 microg/ml) solution was used as a positive control. No effects on plants or earthworms were observed. Significant effects on soil phosphatase activity, indicating effects on soil microorganisms, were observed at the highest exposure dose, affecting all soil layers in the doxycycline-solution-treated MS 3 (positive control) but only the top layer in the spiked pig manure system. Chemical analysis confirmed the different behavior of doxycycline in both systems (with and without manure) and those effects were observed in soil with measured concentrations over 1 mg/kg soil. The detection of doxycycline in leachates revealed a potential mobility. Leachate concentrations were similar for doxycycline solution and spiked manure treatments.  相似文献   

17.
路用砂类盐渍土盐胀及融陷特性试验研究   总被引:2,自引:0,他引:2  
砂类硫酸盐及亚硫酸盐渍土广泛分布于中国西部地区,研究其作为路堤填料的可用性,可充分利用当地资源和节约建设资金。以路基填筑标准及合理的防排水设施为前提条件,基于5 mm筛法配制盐分,研究了不同含盐量水平下砂类盐渍土的盐胀变化特点和在冻融循环作用下砂类盐渍土体的融陷特性,试验结果表明:砂类亚硫酸盐渍土比砂类硫酸盐渍土的盐胀起胀温度和敏感温度区间低约5℃;对于4砂类硫酸盐渍土,含盐量不大于1%时,盐胀率小于1.5%;对于砂类亚硫酸盐渍土,含盐量小于2.3%~2.5%时,盐胀率小于1%;在冻融循环作用下,砂类亚硫酸盐渍土具有较强的融(溶)陷特性;路面容许变形量取2 cm,下路堤填筑厚度为2.0 m时,砂类硫酸盐渍土的含盐量极限值为1.0%,砂类亚硫酸盐渍土的含盐量极限值为2.3%。  相似文献   

18.
Subsurface transport of Cd, Cr, and Mo mediated by biosolid colloids   总被引:4,自引:0,他引:4  
The potential of biosolid colloids to transport metals associated with organic-waste amendments through subsurface soil environments was investigated with leaching experiments involving undisturbed soil monoliths. The monoliths (25 cm in height and 18 cm in diameter) were carved from the upper solum of an Alfisol, a Mollisol, and an Entisol in the Bluegrass region of Kentucky. Biosolid colloids were fractionated from two municipal wastes (lime-stabilized/LSB, and aerobically-digested/ADB), and a poultry-manure (PMB) organic waste and applied onto the monoliths at a rate of approximately 0.7 cm/h. Eluents were monitored for soluble and sorbed Cd, Cr, and Mo concentrations over 16-24 pore volumes of leaching. Colloid-free solutions with metal concentrations similar to those of the biosolid colloids were used as controls. The results indicated significantly (P<0.05) higher (up to 4 orders of magnitude) cationic and anionic metal elutions in association with the biosolid colloids in both, total and soluble fractions, over the control treatments. The elution of significant soluble metal loads in association with the biosolid colloids is attributed to increasing organic-metal complexation and exclusion processes, and emphasizes their importance as contaminant carriers and facilitators. Eluted metal loads varied with metal, colloid, and soil type, following the sequences Mo>Cd>Cr for the metals, and ADB>PMB>LSB (Cd and Cr) or ADB>LSB>PMB (Mo) for the colloids. Metal elution was generally enhanced by soil macroporosity and increasing OM content, while pH and Fe-Al oxides had significant, but opposite effects for the elution of cationic and anionic metal forms. Colloid and metal breakthrough curves were correlated well, being mostly asymmetrical with several maxima and minima caused by multiple clogging and flushing cycles. Soil- and colloid-metal sorption affinities were not reliable predictors of metal attenuation/elution loads, underscoring the dynamic nature of transport processes. The findings demonstrate the important role of biosolid colloids as contaminant carriers and the significant risk they pose, if unaccounted, for soil and ground water contamination in areas receiving heavy applications of biosolid waste amendments.  相似文献   

19.
上海古树生长环境的土壤质量及评价   总被引:2,自引:0,他引:2  
对上海14个区32个古银杏、古香樟的样点进行了土壤质量调查、测试与分析,结果表明:上海古银杏、古香樟生长环境的土壤总体上含水量偏高,密度偏高,通气孔隙度低,通气性差;土壤pH值中性偏碱性;有机质、氮、磷含量偏低。这些因素会对古银杏、古香樟的生长造成不利的影响。对存在的问题提出了相应的改良措施。  相似文献   

20.
介绍了孟村回族自治县辛店镇水土保持项目的基本情况,阐述了项目建设的主要内容,提出了项目区的工程项目建设方案,并对该水土保持项目的社会经济效益进行了分析,以实现改善生态环境的目的。  相似文献   

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