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1.
生产建设项目水土保持方案是水行政主管部门管理生产建设项目水土保持工作的重要抓手。根据全国水土保持信息管理系统和湖北省水土保持公报相关资料数据,对湖北省近年水土保持方案审批数量和范围变化情况、审批项目类型变化情况、编制单位编制项目数量等进行分析,探讨了"放管服"改革新形势下湖北生产建设项目水土保持方案管理在审批方式、审批质量和监管方式等工作中的一些想法和思考。  相似文献   

2.
正为落实国务院深化"放管服"改革精神,进一步规范审批、优化服务、提高效率,加快推进重大投资项目开工建设,9月2日,水利部印发了《关于下放部分生产建设项目水土保持方案审批和水土保持设施验收审批权限的通知》(水保[2016]310号),自10月1日起施行。《通知》提出,原应由水利部审批水土保持方案和验收水土保持设施的生产建设项目中,  相似文献   

3.
生产建设项目水土保持综合评价   总被引:6,自引:2,他引:4  
生产建设项目水土保持综合评价是不同项目分类治理的依据。采用层次分析法,以生产建设项目水土保持最主要的水土流失状况、水土保持防治效果、水土流失危害3个方面为基础,构建了水土保持评价模型,并对不同类型生产建设项目水土保持效益进行了分析。结果表明,点状生产建设项目水土保持效益要大于线状项目,点状项目水土保持效益波动性比线状项目要小;点状生产建设项目中房地产类项目水土保持效益最大,其次为电厂项目,最后为矿场项目,水土保持效益波动性从大到小顺序依次为电厂项目、矿场项目、房地产项目。  相似文献   

4.
根据水利部《关于加强大型开发建设项目水土保持监督检查工作的通知》要求,结合多年对水利部批复水土保持方案的大型生产建设项目水土保持督察工作实际,将大型生产建设项目水土保持督察内容分为行政许可审批情况、组织管理情况、保障措施、水土流失预防和治理情况、监督管理情况等几个部分,并提出各项督察的关键点。  相似文献   

5.
基于深圳市生产建设项目的水土流失特点,分析深圳市生产建设项目水土保持分类分级管理的现状及存在问题,将生产建设项目按照水土流失风险等级分类,对水土保持方案管理、水土保持方案审批、水土保持方案技术要求、水土保持监督检查、水土保持监测、水土保持设施验收等方面提出了具有针对性的管理办法,为形成科学合理的深圳市生产建设项目水土保持分类分级管理方法、提高水土保持精细化管理水平提供参考。  相似文献   

6.
生产建设项目水土保持分类与分类管理对策   总被引:5,自引:0,他引:5       下载免费PDF全文
[目的]系统总结生产建设项目水土流失特征,分析管理工作现状与存在问题,提出实行分类管理的具体意见。[方法]采用调查分析法,调查国家级、不同水土流失类型区的省级及其典型县生产建设项目水土保持管理的经验与成效,分析生产建设项目分类管理的实践经验。[结果]按照项目水土流失影响特征、影响程度以及项目所在地域地形特点和水土保持敏感程度,进行分类管理。[结论]根据分类结果,将水土保持方案编报划分为报告书、报告表和报告简表三类,在方案审批中的审查、审批、变更、公示环节,方案实施中的监督检查、水土保持监理、监测工作,项目竣工时的水土保持验收环节分别实行不同的管理程序并提出要求。  相似文献   

7.
生产建设项目水土保持方案的分类管理   总被引:2,自引:0,他引:2       下载免费PDF全文
[目的]研究生产建设项目水土保持方案实施分类管理,实现管理精细化,以满足新时期简政放权,提高行政效能的要求。[方法]采用模糊聚类法,将全国31类生产建设项目划分为极严重、严重、一般、较轻微和轻微5个水土流失程度等级。[结果]根据项目区域敏感性和所在地区敏感性分析结果,将生产建设项目划分为极敏感、敏感和轻度敏感3个水土保持敏感等级。综合分析生产建设项目的水土流失程度、水土保持敏感性和项目规模,将生产建设项目划归A,B,C 3个水土保持管理级别。[结论]对于A类项目,从水土保持方案编制、后续设计到方案审批各环节均应采取非常严格的管理措施。B类项目中极敏感和敏感程度的项目也应该采取较严格的管理措施。对于C类项目可以简化有关管理程序。  相似文献   

8.
开发建设项目水土流失影响度评价方法研究   总被引:2,自引:0,他引:2       下载免费PDF全文
 为落实树立科学发展观、建设资源节约型社会和环境友好型社会的要求,开发建设项目水土保持方案审批已成为项目核准的必备要件,并正在向选优审批转变。开展水土保持损益分析就是为优化审批水土保持方案提供科学依据。其中开发建设项目水土流失影响度是其核心内容,将开发建设项目的影响时间、扰动后的侵蚀强度、影响范围、可恢复程度和生产运行期影响5个主导因子拟合为一个综合评价模型定量计算,分析开发建设项目对水土流失的影响,并以水土流失影响度为标准,客观评价开发建设项目,为政府行政决策和宏观调节提供科学支撑。  相似文献   

9.
《中国水土保持》2014,(4):F0002-F0002
<正>自2011年3月1日新水土保持法施行以来,长江水利委员会通过送法上门、开展培训、召开座谈会等形式广泛宣传,深化水土保持监督检查联动机制,联合相关流域机构、省(区、市)水行政主管部门和相关行业主管部门对351个部批大型生产建设项目开展了水土保持监督检查,实现了新水土保持法颁布实施以来的部批在建生产建设项目监督检查全覆盖,有效推动了生产建设项目水土保持"三同时"制度的落实。流域各地积极推进新水土保持法配套法规建设,规范水土保持行政许可,强化生产建设项目水  相似文献   

10.
"放管服"改革以来,生产建设项目水土保持工作管理机制也有了重大变革,取消了水土保持方案编制资质和技术从业人员上岗证管理制度,水土保持方案报告书(表)技术审查和审批有的地方由水行政主管部门或其委托的第三方技术服务机构负责组织,有的地方则由行政审批局负责组织,无法保证水土保持方案报告书(表)的质量,影响了生产建设项目水土保...  相似文献   

11.

Purpose

Rice-paddy-dominated watersheds in eastern China are intensively cultivated, and lands with two crops receive as much as 550–600 kg?ha–1?year–1 of nitrogen (N), mainly through the addition of N-based fertilizers. However, stream N concentrations have been found to be relatively low. Waterways in the watersheds are assumed to be effective “sinks” for N, minimizing its downstream movement. We directly measured net sediment denitrification rates in three types of waterways (ponds, streams/rivers, and a reservoir) and determined the key factors that control net sediment denitrification. Such information is essential for evaluating the impact of the agricultural N cycle on the quality of surface water.

Materials and methods

The pond–stream–reservoir continuum was sampled every 2 months at nine sites in an agricultural watershed between November 2010 and December 2011. Net sediment N2 fluxes/net sediment denitrification rates were determined by membrane inlet mass spectrometry and the N2/Ar technique. A suite of parameters known to influence denitrification were also measured.

Results and discussion

Net denitrification rates ranged between 28.2?±?18.2 and 674.3?±?314.5 μmol N2–N?m–2?h–1 for the streams, 23.7?±?23.9 and 121.2?±?38.7 μmol N2–N?m–2?h–1 for the ponds, and 41.8?±?17.7 and 239.3?±?49.8 μmol N2–N?m–2?h–1 for the reservoir. The mean net denitrification rate of the stream sites (173.2?±?248.4 μmol N2–N?m–2?h–1) was significantly higher (p?<?0.001) than that of the pond sites (48.3?±?44.5 μmol N2–N?m–2?h–1), and the three types of waterways all had significantly higher (p?<?0.01) mean net denitrification rates in summer than in other seasons. Linear regression and linear mixed effect model analysis showed that nitrate (NO3 ?–N) concentration in surface water was the primary controlling factor for net sediment denitrification, followed by water temperature. Using monitoring data on NO3 ?–N concentrations and temperature of the surface water of waterways and an established linear mixed effect model, total N removed through net sediment denitrification in the pond–stream–reservoir continuum was estimated at 46.8?±?24.0 t?year–1 from July 2007 to June 2009, which was comparable with earlier estimates based on the mass balance method (34.3?±?12.7 t?year–1), and accounted for 83.4 % of the total aquatic N. However, the total aquatic N was only 4.4 % of the total N input to the watershed, and thus most of the surplus N in the watershed was likely to be either denitrified or stored in soil.

Conclusions

High doses of N in a rice-paddy-dominated watershed did not lead to high stream N concentrations due to limited input of N into waterways and the high efficiency of waterways in removing N through denitrification.  相似文献   

12.
参考作物蒸散量(ET_0)是确定植被生态系统需水量的关键因子,其时空分布特征及主要影响因素分析对于制定植被恢复策略与区域水资源配置方案具有重要意义。本文基于FAO-56 Penman-Monteith公式和广西地区25个气象站点1960—2010年的逐日资料,计算了各站点的ET_0,在此基础上采用GIS的克里金插值、Spearman秩次相关法和通径分析方法分析了广西喀斯特与非喀斯特地区ET_0的时空变化特征及其影响因子。结果表明,51年来广西各站点多年平均ET_0为1 138 mm×a~(-1);空间分布呈由南向北、由低纬度向高纬度递减的特征,高值区主要分布在非喀斯特地区,低值区主要分布在喀斯特地区。喀斯特与非喀斯特地区年ET_0累积距平曲线均呈"N"型分布;20世纪70年代最高,90年代最低,21世纪以来年ET_0有所回升,但仍低于51年平均值。此外,喀斯特地区ET_0年际变化小于非喀斯特地区。日照时数、风速和平均温度是影响非喀斯特地区年ET_0变化的主要气象因子,而相对湿度则通过与其他气象因子的相互作用间接对喀斯特地区年ET_0的变化产生较大影响。在季节尺度上,日照时数和平均气温在各季节都是ET_0最主要的影响因子,与ET_0呈正相关关系;风速在喀斯特地区冬、春两季对ET_0的间接作用系数为负,在非喀斯特地区并未发现这一现象。了解不同地区ET_0的变化趋势是植被生态需水定额计算的必要措施。  相似文献   

13.
A protozoological survey was performed on a waste-stabilization pond to isolate, identify, and determine the incidence of ciliates present in these waters. The correlation between the species found and the physicochemical parameters was investigated. One hundred and eighty samples were analyzed from February 1983 to February 1984. Free-living ciliates isolated include:Carchesium polypinum Linnaeus,Vorticella microstoma Ehrenberg,Vorticella convallaria Linnaeus,Didinium balbiani Fabré-Domergue,Amphileptus claparedei Stein,Spathidium spathula Müller,Litonotus fasciola Ehrenberg,Paramecium caudatum Müller,Paramecium aurelia Ehrenberg,Tetrahymena vorax Kidder,Tetrahymena pyriformis Ehrenberg,Cyclidium glaucoma Müller,Aspidisca costata Ehrenberg, andStylonychia putrina Stokes. The performance of the pond was predominantly anaerobic. The temperature, total alkalinity, and nitrate concentration were the most variable parameters in the system studied.  相似文献   

14.
Abstract

Earlirose rice (Oryza sativa L. ) and Hawkeye soybeans (Glycine max L.) were grown in solution culture with A12(SO4)3 in concentrations of 0, 10‐6, 10‐5, 10‐4, 10‐3 M. Only at 10‐4 (slightly) and at 10‐3 M were there yield depressions due to Al. The threshold concentration of Al for toxicity was about 20 μg/g in rice shoots and about 30 μg/g in soybean leaves. The solution level necessary for these concentrations was 8 μg Al/ml. Plant concentrations which caused severe toxicity were 70 μg Al/g plant with 81 μg Al/ml solution. Most Al remained in roots, but leaves contained more than did stems of soybeans. The high Al decreased Fe, Cu, and Mn concentrations in shoots of rice and decreased Fe, Cu, and Zn in roots of rice. The high Al resulted in decreased Fe and Zn in leaves of soybeans. No Fe deficiency symptoms were present due to the high Al.  相似文献   

15.
2013年我国种植业化肥施用状况分析   总被引:25,自引:5,他引:25  
【目的】我国农用化肥消费量大,数据来源不同,统计口径各异,行业内大多引用国家统计局公布的数据,但该数据无法推算出氮肥、磷肥、钾肥分类消费量。我国区域间、季节间、作物间化肥消费情况的报道很少,在调节化肥供需、指导化肥行业健康发展时显得依据不足。调查种植业化肥施用状况可以为指导肥料生产、供应提供重要依据。【方法】以农业部339个国家级基层肥料信息网点为依托,根据我国农业生产习惯和我国政府部门统计习惯,将一年分为三个用肥季,1 5月份为春耕季,6 8月份为夏播季,9 12月份为秋冬种季。在三个季节,每个网点随机调查30个农户的主要种植作物施用氮肥、磷肥、钾肥、复合(混)肥(包括配合式)量,经两级土壤肥料部门审核后,采用省份、相似种植区域、全国三级逐级加权平均的方法,推算了不同区域、不同季节、不同作物单位面积施肥量;再用作物单位面积施肥量、该作物全国种植总面积、样本中施肥面积占该作物种植面积的比例推算了作物全年、不同季节化肥施用量。同时,分析了主要作物、不同季节化肥施用状况以及供需平衡情况,不同季节、不同区域供肥情况和农民的购肥习惯。【结果】2013年我国种植业化肥施用量5498万吨(折纯下同),其中,氮肥(实物量)3382万吨,磷肥1175万吨,钾肥941万吨。粮食作物化肥总用量为2782万吨,占种植业化肥总用量的50.6%;其次是果树和蔬菜,三类作物占种植业化肥施用总量的82.8%,经济、园艺作物单位面积化肥施用量大于粮食作物。春耕、夏播、秋冬种化肥施用量分别占全年化肥施用量的34.2%、35.6%、30.2%。复混肥料和尿素是农民最常购买的两种肥料,从全年来看,农民施用复混肥料和尿素的样本数分别占总样本数的72.5%和71.6%,春耕、夏播、秋冬种农民购买尿素和复合(混)肥的样本数分别占该阶段样本数的70.9%和62.9%、84.9%和78.1%、56.6%和83.9%。春耕和夏播时期农民多数选用尿素,秋冬种多数选用复混肥料,东北、西北、华中南地区农民多选用尿素,华北、西南、华东地区农民多选用复混肥料。另外,我国氮肥、磷肥供应分别过剩1080万吨、680万吨,钾肥缺口370万吨,供需矛盾突出。氮、磷、钾养分配合式为15-15-15的复混肥样本数占农民选购复混肥总样本数的33.3%,说明复混肥养分结构不尽合理。【结论】建议国家进一步遏制氮肥、磷肥过剩产能,优化产品结构,大力推广科学施肥技术。  相似文献   

16.
A simple method (the inversed auger hole method) for measuring field-saturated hydraulic conductivity (Kfs) was investigated. Measurements were carried out in the spring, summer and autumn at three depths in two Swedish clay soils (Ultuna and Limsta, with clay contents of 45–60%0 and 65–80%, under barley and grass/clover ley respectively). Seasonal fluctuations in Kfs at Limsta were more pronounced, and were observed deeper in the profile. This was attributed primarily to larger structural changes due to a higher capacity for swell/shrink (normal shrinkage over the available water range) and an earlier drying up of the soil under grass/clover ley. It was shown that the measured Kfs values were strongly correlated with the total inter aggregate (macro-) porosity (et), estimated from a simple model of soil shrinkage. Combining the data from both soils, a single power-law relation was adequate (r= 0.73) to describe the variations in Kfs with et  相似文献   

17.
A study was made of the formation of anaerobiosis in a waterlogged soil. A dilute soil suspension containing NO?3, Fe3+, sodium citrate, a limited amount of O2, and trace elements was used as a model of waterlogged soil. Polarography was used to detect dissolved O2, Fe3+ and Fe2+. The fates of the NO?3 and Fe3+ during and after O2 consumption by the microorganisms were studied in a specially designed vessel. A close correspondence was obtained between the reduction of NO?3, NO?2 and Fe3+ and the growth of denitrifying bacteria in the closed system employed. From the experimental results we presume that microorganisms which respire NO?3 are also capable of utilising Fe3+ in their respiration. The mechanisms of reduction of these chemical species by the microorganisms are also discussed, emphasising the possibility of the participation of chemical reduction of NO?2 by Fe2+ in the over-all reduction process.  相似文献   

18.
Chinese cabbage plants [Brassica pekinensis (Lour) Rupr. cv. Nagaoka 50] were cultivated experimentally for two years (1993 and 1994) using a semi‐forcing technique of floating rowcovers, polyethylene (T1), polypropylene (T2), versus no floating row‐covers, control (T0). Five samplings were made, taking four plants per each replication and total phosphorus (P) (Ptotal), inorganic P (Pi), and calculated organic P (Porg) were determined as well as foliar acid phosphatase activity (FAPA). The aerial and root temperatures of the treatments T1 and T2 exceeded those of T0. The Ptotal concentration showed no significant variations with treatment, whereas the Pi concentrations increased in Ti and T2 and Porg decreased in both treatments with respect to T0. The FAPA was influenced a similar way as Pi, raising with temperature. The contents (mg plant‐1) of Ptolal, Pi, and Porg were greater in T1 and T2 than in T0, and this could be due to the fact that the highest temperatures (root and aerial zone) generated by the plastic rowcovers favored the absorption of P, thereby boosting FAPA and the fresh and dry weights, and yield.  相似文献   

19.
Proteolytic bacterial communities, which mineralize organic nitrogen, play a key role in agricultural systems. In this study, alkaline metalloprotease (apr) gene fragments from proteolytic bacteria were investigated in bulk and rhizosphere paddy soil from four fields under organic management (for 2, 3, 5, and 9 years), and from one field under conventional management (for 2 years). We analyzed the abundance and structure of the proteolytic bacterial communities using real-time quantitative PCR and denaturing gradient gel electrophoresis. Our results showed that the abundance of proteolytic bacteria ranged from 1.57?×?108 to 8.02?×?108?copies/g of soil. In addition, the abundance of the proteolytic bacteria in the paddy soils under organic management was significantly higher than those in the paddy soil under conventional management. Moreover, the gene copy numbers in the rhizosphere soils were significantly higher than those in the bulk soils. The abundance of proteolytic bacteria tended to increase with the duration of organic management, with the highest abundance being found in the soil that had been under organic management for 5 years. However, the proteolytic bacteria communities in the paddy soils were not significantly affected by management practices. Phylogeny analysis showed that all gel bands obtained represented genes from Pseudomonas. Additionally, correlation analysis and canonical correspondence analysis showed that C/N, C, and N were important factors that influenced the abundance and community structure of the proteolytic bacteria. These results suggest that proteolytic bacteria are indicators in organic management systems, depolymerize organic N and hence maintain soil sustainability.

Abbreviations: CM: conventional management; OM: organic management; DGGE: denaturing gradient gel electrophoresis; qPCR: real-time quantitative PCR detecting system; COFCC: China organic food certification center; CCA: canonical correspondence analysis  相似文献   

20.
This study evaluates soil properties in organically managed olive groves and natural zones in a mountainous area of Andalusia, Spain. Two soil types (Eutric Regosol and Eutric Cambisol) and the most common soil management methods (tillage and two intensities of grazing) were studied. Both soil types in the groves had values not much lower than those in the natural areas. Average (±SE) values in the groves were 1.58 ± 0.71% for organic carbon, 323 ± 98 g kg?1 for macroaggregate stability, 1.11 ± 0.16 g cm?3 for bulk density, 3.5 ± 1.6 mm h?1 for saturated hydraulic conductivity and 1209 ± 716 mg CO2 kg?1 for soil respiration. Overall, these values tended to be lower in the tilled compared with that in the grazed groves. The average phosphorus soil content (5.83 ± 5.22 mg kg?1) was low for olive production and within adequate ranges for N (0.12 ± 0.05%) and K (142 ± 81 mg kg?1). Soil erosion was high in the tilled groves (35.5 ± 18.2 t ha?1 year?1) with soil loss correlating with indicators of soil degradation such as organic carbon content and water stable macroaggregates. In the grazed groves, soil loss was moderate with no clear indications of soil degradation. Overall, there was significant farm‐to‐farm variability within the same soil and land management systems. Olive production had a moderate effect on soil degradation compared with natural areas and olive cultivation could be sustained in future if cover crop soil management replaced tillage, especially in the most sloping areas.  相似文献   

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