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1.
不同土地利用条件下土壤质量综合评价方法   总被引:18,自引:5,他引:18  
针对传统的土壤质量评价方法难以满足现代农业发展的现状,提出了一种土壤质量指数法(SQI)综合评价土壤质量,旨在为农业生产、农产品产地选址、农业环境保护等提供理论支撑和参考依据。将方法在北京市郊区7种土地利用方式(粮田、林地、湿地、荒地、果园、菜地、草地)上进行了应用,并与常规方法进行了对比,结果表明:采用隶属度模型评价土壤肥力,肥力高低顺序为:湿地>菜地>粮田>林地>果园>荒地>草地;采用内梅罗污染指数评价了重金属污染状况,污染程度高低顺序为:湿地>菜地>荒地>果园>林地>粮田>草地;采用SQI指数评价土壤综合质量,其综合质量的高低顺序为:湿地>粮田>菜地>果园>林地>荒地>草地。此外还对评价模型的适用范围、评价结果的划分等一系列关键问题进行了探讨,得出:SQI指数评价方法的应用及结果的划分涵盖了不同的土地利用方式的农用地,体现了各种土壤属性的差异和变异特性,评价结果可实现土壤综合质量定性和定量化,能够反映土壤的关键信息,符合农业生产需要。  相似文献   

2.
一种基于模糊的修复后土壤环境风险综合评价方法   总被引:3,自引:0,他引:3  
Environmental risks pertaining to contaminated soils have been well studied, while little attention has been paid to the risks of the soils after remediation. In this study, a concept model developed based on fuzzy set theory was applied to evaluate the uncertainties of three risk indicators, namely, plant growth, groundwater safety and human health, of a restored site that had been previously polluted by heavy metals. The concept model classified the grade and importance of risk factors by an 11-level ranking system and was able to yield a comprehensive risk result rather than multi-risk results for complex risk indicators. Modeling results showed that the risks to the three indicators were effectively reduced after the remediation. Moreover, great sensitivity of the risks was found related to the weight distribution among the three risk indicators. In general, the risks of both polluted and restored soils to the environment were in the order of groundwater safety 〉 plant growth 〉 human health. The model was proved to solve the problems of multi-risk results due to complex risk indicators that previously encountered by other researchers, which made it helpful in decision-making and management of restored soils.  相似文献   

3.
A method of determining the parameters of the soil state and assessing the quality of soils subject to anthropogenic loads was substantiated. An equation for the state function was derived in the general form, and a method was proposed for determining the equation parameters based on the interpretation of the experimental “dose-response” relationships. A schedule was developed for the environmental assessment of the soil quality. Procedures were substantiated and specified for assessing the state and quality of erosion-hazardous soils, the quality of the air with an unorganized dust source, the state and quality of the water on the basis of biotesting, the integrated assessment of the soil state under multiple loads, and the environmental-economic assessment of the quality of lands and waste disposal sites.  相似文献   

4.
土地质量评估与监测: 土壤科学面临的新挑战   总被引:15,自引:0,他引:15  
Sustainable land management (SLM)is the key to harmonizing environmetal and ecolgical concerns of society with the economic realities of producing adequate food and fiber of high quality and ensuring a absi minimal quality of life.The aim of SLM is to maintain the integrity of the biophysical land resource base,but it can only be realized if land users understand the impacts of land management options on their lands but also on other off-site areas and can optimize the socioeconomic and environmetal benefits of their choice.To Facilitate this,the Contribution of soil suvery organizations would be through the assessment and monitoring of land quality.Land quality is a measure of the ability of land to perfor specific functions and is derived by an integration of soil survey information with other environmental,and if necessary,socioeconomic information.The desired reliability influences the operational scale of the assessment,Such an assessment would assist in:1) locating homologous areas for research sites or for transferring technologies;2) providing the geographic basis for systems analysis(e.g.modeling);3) serving as a basis for local,natinal and global resource assessment and monitoring;4) providing an ecosystem context for land use,assessments of temporal and spatial variability,and impact of human interventions;5)serving as a framework for more detailed assessment for all levels of interest;and 6) evaluating global issues such as food security,impacts of climate change,biodiversity montoring,and addressing desertification.Based on an evaluation of the progress made in soil resource inventories and considering the demands of the environment focused world,the paper considers the need for counteries to mount such a program.The authors believe that this is the next demand of soil science and that we can fulfill our soical contract by periodically providing such information on the state of a nation‘s land resource.  相似文献   

5.
Journal of Soils and Sediments - Urban roadside soils are important growth media for roadside trees. However, typical assessment variables are limited in describing the characteristics of roadside...  相似文献   

6.
Rapid soil testing and soil quality assessment are essential to address soil degradation and low farm incomes in smallholder farms. With the objective of testing diffuse reflectance spectroscopy (DRS) to rapidly assess soil chemical properties, nutrient content and a soil quality index (SQI), samples of surface soil were collected from 1113 smallholder farms in seven districts in Bundelkhand region of Uttar Pradesh, India. A minimum dataset (MDS) approach was followed to estimate SQI using the three chemical parameters of soil pH, electrical conductivity (EC) and soil organic carbon (SOC), and 11 different soil nutrients. Principal component and correlation analyses showed that soil pH, SOC content and three available nutrients − copper (Cu), iron (Fe) and sulphur (S) − may constitute the MDS. Estimated SQI values showed strong positive correlation with crop yields. Results of chemometric modelling showed that the DRS approach could yield the coefficient of determination (R2) values in the validation datasets ranging from 0.79 to 0.94 for exchangeable calcium (Ca) followed by 0.67–0.88 for exchangeable potassium (K), 0.52–0.86 for SOC and 0.53–0.81 for available boron (B) content. Except in one district, the DRS approach could be used to estimate SQI values with R2 values in the range of 0.63–0.81; an R2 value of 0.71 was obtained in the pooled dataset. We also estimated the three-tier soil test crop response (STCR) ratings to compare DRS and wet chemistry soil testing approaches. Similar STCR ratings were obtained for both these approaches in more than 86% of the samples. Parameters for which both the methods yielded similar ratings in more than 80% of the samples were EC (>98%), pH and exchangeable Ca (>81%) and available B (>89%). With similar ratings, these results suggest that the DRS approach may safely be used for farmers' fields, replacing the traditional wet analysis approach of soil testing.  相似文献   

7.
No-tillage (NT) farming offers innumerable benefits to soil and water conservation, however, its potential to sequester soil organic carbon (SOC) and related soil properties varies widely. Thus, the impact of long-term (>4 yr) NT-based cropping systems on SOC sequestration and selected soil physical and chemical parameters were assessed across soils within five Major land Resource Areas (MLRAs: 99 and 111 in Michigan; 124 and 139 in Ohio; and 127 in Pennsylvania) in eastern U.S.A. Soil samples were collected from paired fields of NT and plow tillage (PT) based cropping systems and an adjacent woodlot (WL). The SOC concentration, bulk density (ρb), texture, pH, electrical conductivity (EC), soil N, coarse particulate organic matter (CPOM) C and N, and nitrate N (NO3-N) concentrations were determined. Conversion from NT to PT practice increased surface soil pH from 5.97, 6.56 and 6.02 to 6.62, 6.91 and 7.09 under MLRAs 127, 111 and 99, respectively. NT soils had higher SOC concentration soils by 30, 50 and 67% over PT soils at 0–5 cm depth under MLRAs 99, 111 and 127, respectively. Considering the whole soil profile SOC, WL had higher SOC pool than NT and PT practices under MLRAs 99, 111 and 124, however, there was no significant difference (P < 0.05) between NT and PT practices across five soils. Almost the same trend was observed in the case of depthwise soil N content. NT soil had higher N content than PT soils by 27, 44 and 54% under MLRAs 99, 127 and 111, respectively. However, whole soil profile N content of NT soil was significantly higher by 12% than PT soil under MLRA 99. Concentrations of CPOM associated C and N of NT soil was higher than PT soil under MLRAs 99, 111 and 127 at 0–5 soil depth. These results indicated that impact of tillage on soil C and associated soil quality parameters is confined within specific soil types.  相似文献   

8.
Soil degradation threatens sustainable food production and accelerates global warming. Poorer countries, whose agricultural sectors are highly dependent on their natural resource bases, are hit particularly hard by declining soil productivity. Calls for soil‐quality monitoring are therefore, justified and this could inform decision‐makers on the preparation of appropriate interventions. However, the provision of monitoring methodologies is not an easy task. Soil degradation affects several soil characteristics that at larger scales cannot be evaluated with models or remote‐sensing techniques. Therefore, this study focuses on investigating the use of field‐based soil assessment methodologies to differentiate degrees of soil degradation. Specifically, we test the Visual Soil Field Assessment Tool (VS‐Fast) for detecting and monitoring soil degradation using a cross‐section of 71 sites in Senegal, the soil quality of which were classed by local experts. We found low correlation between VS‐Fast classes and expert assessments. By using an ordered logit model to quantify class boundaries, we show that experts categorized areas as ‘degraded’ for a wider range and higher VS‐Fast scores than the corresponding VS‐Fast class. Yet, from general linear models and analysis of variance procedures we found that areas classed by experts as ‘degraded’ had statistically significant lower VS‐Fast scores compared to those that were judged as ‘normal’ and ‘good’, while differences of the VS‐Fast scores between the latter two were negligible. It is remarkable that the visual assessment, the cheaper component of the VS‐Fast score, performs better in differentiating degradation status than its measured counterpart. The results support the need to investigate the applicability of other VSA methodologies that only use field observations and tactile methods.  相似文献   

9.
Rat bioassay was used to assess the protein quality of powdered infant formulas and to evaluate the feasibility of using modified casein diets (containing the same source and level of fat and carbohydrate contributed by the infant formulas) as reference standards. Modification of the casein diet to match the milk-based formulas caused a significant reduction in weekly protein efficiency ratios (PER) and net protein ratios (NPR) at the third and fourth weeks. Modification of the casein diet to stimulate the soy-based formulas had no significant effect on NPR values; PER values were more varied. When PER and NPR values of the powdered milk-based formulas were expressed relative to the unmodified reference standard, the relative values were lower than when each matched reference was used. With few exceptions, the relative weekly PER values of the soy-based formulas were similar regardless of the standard used. The relative NPR values of the formulas had a pattern similar to the relative PER values. The data indicate that protein quality evaluation of infant formulas using rat bioassay warrants the use of matched casein reference diets for each type of formula.  相似文献   

10.
Local communities often have substantial knowledge related to trends in soil quality and the associated limiting factors. Despite this, soil quality (SQ) degradation is a critical problem in Ethiopia and there is little or insufficient scientific information documenting local community experience in assessing SQ. This paper presents experiences of local communities in diagnosis of SQ and assesses the contribution of local knowledge as a strategy for sustainable development decision making within the Mai-Negus catchment of northern Ethiopia. Participatory transect-walks, group discussions and field observation which complemented by household interview were used to acquire data. Farmers identified SQ indicators e.g., crop yield, soil depth, erosion and sedimentation as their basis of categorizing the soils into high, medium and low SQ. They were also able to identify severely degraded areas (hotspots) and underlying causes. Significant variations (P ≤ 0.05) were shown between the proportions of farmers used certain SQ indicator and those who didn't while categorizing SQ. Local farmers involved in this study demonstrated their capability to suggest appropriate land management solutions for specific problems. This study demonstrates the benefit of involving local farmers in both problem identification and solution development so that anti-degradation technologies can easily be implemented and adopted.  相似文献   

11.
长期不同施肥制度土壤肥力特征综合评价方法   总被引:48,自引:9,他引:48  
通过综合分析不同施肥制度下土壤物理、化学、生物学特征来评价不同施肥体系培肥土壤能力,以期建立科学施肥制度,为实现土壤可持续利用提供理论依据。以位于中国农业科学院禹城试验基地长达26 a的不同施肥定位试验为平台,研究了长期不同施肥对2种土壤物理肥力指标、10种化学肥力指标及2种土壤生物肥力指标的影响,运用主成分分析和聚类分析等数理统计方法综合评价了长期不同施肥制度下土壤物理肥力、化学肥力及生物肥力因子,并对不同施肥制度土壤肥力水平进行综合评分。结果表明:1)不同施肥制度对土壤肥力因子影响差异显著。单施有机肥及有机无机配施与单施化肥相比,土壤容重降低5.0%~11.0%,土壤总孔隙度增加4.1%~9.9%:土壤有机碳、全氮增加95%~136%、69%~137%,土壤速效磷含量增加5倍,土壤速效钾增加81%~103%;土壤微生物碳、氮分别增加50%~112%、34%~79%,土壤pH值下降了0.15~0.47个单位。2)将14个土壤肥力因子分为2个主成分综合表征土壤肥力,其中土壤容重、土壤孔隙度、土壤全碳、土壤活性有机碳、土壤全氮、土壤有机氮、土壤微生物碳、土壤微生物氮、土壤速效钾、土壤全磷、土壤速效磷、土壤有机磷、pH值等肥力因子在主成分一上有较高的负荷,贡献率83.73%;土壤全钾在主成分二上有较高的负荷,贡献率8.49%。3)聚类分析方法把不同施肥制度对土壤肥力的影响差异强度分为4类:常量有机肥和常量有机无机配施、常量化肥和高量化肥、不施肥、高量有机肥。4)不同施肥制度对土壤培肥效果依次表现为:高量有机肥常量有机肥常量有机无机配施高量化肥常量化肥不施肥。单施有机肥以及有机无机肥配施与单施化肥相比能有效增加土壤养分含量,调节土壤养分平衡,能从土壤物理、化学、生物肥力方面综合提升土壤肥力水平,提高土壤养分供应能力。  相似文献   

12.
13.
Soil quality is a concept that integrates soil biological, chemical and physical factors into a framework for soil resource evaluation. Conventional tillage practices can result in a loss of soil organic matter and decreased soil quality. The potential for soil quality degradation with tillage may vary depending upon landscape position and the spatial distribution of critical soil properties. Information on how to accurately integrate soil spatial information across fields, landscapes and watersheds is lacking in the literature. The primary objective of this study was to evaluate the long-term effect of conventional and ridge-tillage on soil quality in three small watersheds at the Deep Loess Research Station near the town of Treynor in southwest Iowa. Soil types included Monona silt loams in summit positions, Ida or Dow silt loams in backslope positions, and Napier or Kennebec silt loams in footslope positions. We removed surface soil cores from transects placed along topographic gradients in each watershed and quantified total soil organic C (SOC), total soil N (TN), particulate organic matter C (POM-C) and N (POM-N), microbial biomass C (MB-C), N mineralization potential (PMIN-N), nitrate N, extractable P and K, pH, water-stable macroaggregates (WSA), and bulk density (BD). We used terrain analysis methods to group the data into landform element classes to evaluate the effect of topographic position on soil quality. Results indicate that soil quality is higher under long-term ridge-tillage compared with conventional tillage. Soil quality differences were consistently documented among the three watersheds by: (1) quantification of soil indicator variables, (2) calculation of soil quality index values, and (3) comparison of indicator variable and index results with independent assessments of soil function endpoints (i.e. sediment loss, water partitioning at the soil surface, and crop yield). Soil quality differences under ridge-till were found specifically for the backslope and shoulder landform elements, suggesting that soil quality increases on these landform elements are responsible for higher watershed-scale soil quality in the ridge-tilled watershed.  相似文献   

14.
The characteristics of the faunal community in soil are closely related to soil quality. Using the soil faunal community as an indicator of soil quality is not cost-effective because of the complex taxonomic distinction and identification required, moreover; the power of the assessment is weak in relation to soil function. Recently, a functional method incorporating eco-morphological traits has been proposed, but it depends upon presence/absence data of soil arthropod community exclusively. To overcome the limitation, we designed a novel index using the diversity of the soil faunal community along with its functional traits, and the abundance of its members (Abundance-based Fauna Index, referred as FAI). The FAI method supports both the presence/absence data and its abundance. Using real and simulated data sets with eco-morphological and niche breadth traits, two taxonomic independent functional traits, we tested associations of FAI values with soil quality and found a good relationship. In addition to its usefulness for measuring soil quality, FAI may provide valuable information for linking functional traits of soil fauna and the belowground environmental condition.  相似文献   

15.
北京地区基本农田土壤环境质量分析与评价   总被引:20,自引:4,他引:20       下载免费PDF全文
对北京地区基本农田的土壤环境质量和污染状况进行了系统的调研,并对采样区农田土壤的环境质量按照国家标准进行了单因子评价和综合评价。结果表明,重金属的污染程度依次为Cd > Cu > As > Pb > Cr > Hg,Cd,Cu,As高于北京市土壤重金属背景值,Pb、Cr接近或略低于背景值,相比较而言,Cd污染为北京市基本农田中的主要污染元素。土壤中的农药残留的主要成分为滴滴涕。只有1处农田的Cd含量超过了国家二级标准限量,其余指标均低于二级标准。整体而言,北京地区的基本农田土壤环境质量属于清洁和安全范围,符合发展都市型现代农业的要求。  相似文献   

16.
海南岛土壤质量系统评价与区域特征探析   总被引:15,自引:3,他引:15  
研究建立了海南岛热带地区土壤质量系统评价模型 ,并对该岛土壤质量进行综合评价 ,结果表明海南岛土壤养分有效性为主要限制因子 ,水分有效性和根系适宜性状较好 ,土壤综合质量中等偏上。与林地相比其他土地利用方式土壤质量均有所下降  相似文献   

17.
Highly precise and reliable determination of heavy metals in soil micro-arthropod tissues remains a challenge because of the small size of the animals and their typical low abundance in metal-contaminated agricultural soils. The present study sought to develop a method for cadmium(Cd) determination in soil micro-arthropods by optimizing the sample digestion procedure, reducing sample weight, modifying sample pre-treatment and validating the methodology with field samples. The optimized digestion conditions comprised a sample mass of 50–150 μg, digestion reagent of nitric acid:hydrogen peroxide(3:1), digestion temperature of 105℃,digestion period of 3 h and digestion volume of 30 μL. Defecation of the standard Collembola Folsomia candida(92 h) and the indigenous Collembola Onychiurus yodai(42 h) and ultrasonic cleaning of F. candida increased the accuracy of Cd determination.The recovery of Cd using the refined procedure was 98.9% and the limits of detection and quantification were 0.002 and 0.008 μg L~(-1), respectively. The within-batch precision values were 3%. The Cd concentrations in the tissues of the Collembola Isotoma sp.collected from a range of metal-contaminated fields determined by the improved method were consistent with the Cd concentrations in the field soils. The results indicate that the optimized method can be used for more accurate or reliable determination of Cd concentrations in soil micro-arthropod tissues.  相似文献   

18.
农业规划战略环境影响评价的基本思路与方法   总被引:2,自引:1,他引:2  
规划战略环境影响评价是从起始源头上来避免或减缓生态环境影响的一项重要工作,在中国还处于探索和总结经验阶段,尤其是农业规划战略环境影响评价,由于涉及面广、范围大、项目多、综合性强,相对其他行业而言更加复杂,目前还处于研究准备阶段.为此,作者对农业规划战略环境影响评价的重要意义和基本思路与方法、要求等进行了研究、探讨和归纳,以供农业行业在今后开展农业规划战略环境影响评价时参考.  相似文献   

19.
The living soil is instrumental to key life support functions (LSF) that safeguard life on Earth. The soil microbiome has a main role as a driver of these LSF. Current global developments, like anthropogenic threats to soil (e.g., via intensive agriculture) and climate change, pose a burden on soil functioning. Therefore, it is important to dispose of robust indicators that report on the nature of deleterious changes and thus soil quality. There has been a long debate on the best selection of biological indicators (bioindicators) that report on soil quality. Such indicators should ideally describe organisms with key functions in the system, or with key regulatory/connecting roles (so-called keystone species). However, in the light of the huge functional redundancy in most soil microbiomes, finding specific keystone markers is not a trivial task. The current rapid development of molecular (DNA-based) methods that facilitate deciphering microbiomes with respect to key functions will enable the development of improved criteria by which molecular information can be tuned to yield molecular markers of soil LSF. This review critically examines the current state-of-the-art in molecular marker development and recommends avenues to come to improved future marker systems.  相似文献   

20.
The term ‘critical body residue’ (CBR) was defined as the lowest observed total body concentration of a contaminant in an organism, which is associated with the occurrence of adverse toxic effects in either individuals or populations of a defined age or stage of development. In this study, internal toxicity thresholds were determined for copper in the clitellated adult stage of earthworms (Lumbricus rubellus and Aporrectodea caliginosa). The objective was to assess the applicability of CBRs as a practical tool in soil quality assessment of contaminated sites and as a means of a sustainable protection of earthworm fauna. Laboratory studies showed that body concentrations of Cu were generally in agreement with the chemically available CaCl2-extractable fraction in soil, but that there was also some evidence of internal pH-related homeostatic regulation. Toxicological correlates of body Cu concentrations with adverse effects on cocoon production (fecundity) suggested an approximate sublethal internal threshold of about 40 mg kg−1, with mortality occurring at about 60 mg kg−1. Adult L. rubellus sampled from areas with a wide range of metal pollution showed body Cu concentrations with a minimum of 8 mg kg−1 and a maximum of 60 mg kg−1. Beyond this apparent physiological tolerance range, environmental management directed at optimal earthworm population survival may not be sustainable in contaminated fields. Studies of L. rubellus colonizing a metal-contaminated experimental sludge-treated field showed that a reduced rate of colonization can already be associated with an average body Cu concentration of 25 mg kg−1. However, in this particular field situation mixture effects of other metals that were also present in the soil and the occurrence of avoidance behaviour during colonization may have contributed to this low internal toxicity threshold. It is concluded that the CBR approach seems to be a feasible option for use as a tool in a bioavailability-based soil quality assessment, even for essential trace metals like copper, but that further insight may be needed to establish the uncertainty and reliability of the application in environmental quality assessment and decision making.  相似文献   

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