Temporal dynamics of ammonia oxidizer (amoA) and denitrifier (nirK) communitieem from Tai Lak
Applied Soil Ecology 48 (2011) 210–218
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Applied Soil
Ecology
j o u r n a l h o m e p a g e :w w w.e l s e v i e r.c o m /l o c a t e /a p s o i
l
Temporal dynamics of ammonia oxidizer (amoA )and denitri?er (nirK )
communities in the rhizosphere of a rice ecosystem from Tai Lake region,China
Qaiser Hussain a ,Yongzhuo Liu a ,Zhenjiang Jin a ,Afeng Zhang a ,Genxing Pan a ,?,Lianqing Li a ,David Crowley b ,Xuhui Zhang a ,Xiangyun Song a ,Liqiang Cui a
a Institute of Resources,Ecosystem and Environment of Agriculture,Nanjing Agricultural University,1Weigang,Nanjing 210095,China b
Department of Environmental Sciences,University of California Riverside,CA 92521,USA
a r t i c l e i n f o Article history:
Received 20October 2010
Received in revised form 28February 2011Accepted 9March 2011Keywords:
Temporal dynamics
Ammonia oxidizer (amoA )Denitri?er (nirK )Rice rhizosphere DGGE qPCR
a b s t r a c t
A ?eld experiment was conducted to investigate the abundance and dynamics of ammonia oxidizer (ammonia oxidizing archaea –AOA and ammonia oxidizing bacteria –AOB)and denitri?er communi-ties in the rhizosphere at four growing stages of rice using PCR-denaturing gradient gel electrophoresis (DGGE)and real-time PCR approaches.Rice plantation promoted greater abundance of amoA (AOA and AOB)and nirK (denitri?ers)genes in the rhizosphere than in the bulk soil,showing a profound rhizosphere effect.Rice growing stages signi?cantly affected the structures and abundances of AO
B and denitri?er (nirK )communities in the rhizosphere,whereas no effect was observed on the community structure and abundance of AOA in the rhizosphere.Moreover,the amoA gene copy numbers of AOA were more than those of AOB in all soil samples.However,denitri?er (nirK )generally dominated the ammonia oxidizer (amoA )in the rhizosphere during all growth stages,suggesting better adaptability of denitri?er in the rice rhizosphere environment.These results further suggest that AOB and denitri?er (nirK )communities associated with rice rhizosphere are highly dynamic in response to prevailing plant and soil conditions over a rice crop season,whereas AOA showed higher stability throughout the rice growing period.
? 2011 Elsevier B.V. All rights reserved.
1.Introduction
Rice is the most important staple food crop for human consump-tion in the world and 75%of the world’s rice production comes from irrigated rice ?elds.Rice paddy soils are also known as appro-priate model systems to investigate essential aspects of microbial ecology,such as dynamics of microbial community structures,abundances and functional relationship between/among microbial groups (Liesack et al.,2000).Plant rhizosphere provides distinct microhabitats with respect to microorganisms as compared to the surrounding bulk soil (Bais et al.,2006).Nonetheless,the rhizo-sphere is highly dynamic as soil micro-biota respond quickly to changes in quantities and chemical composition of root exudates,which are considered to be crop varieties and growing stage spe-ci?c (Whipps,2001;Rengel,2002).Many ?eld or microcosm studies have been focused on the in?uence of plants on the overall micro-bial structures in the rhizosphere based on 16S rRNA gene analysis (Smalla et al.,2001;Wieland et al.,2001;Kennedy et al.,2004).
Alternation of water-logging and drainage condition,as unique water regime for rice production,allows shifts of redox potential
?Corresponding author.Tel.:+86254396027;fax:+86254396027.
E-mail addresses:gxpan@https://www.wendangku.net/doc/081363651.html, ,pangenxing@https://www.wendangku.net/doc/081363651.html, (G.Pan).and various biochemical processes such as ammonium oxidation and nitri?cation in paddy soils (Kikuchi et al.,2007).Moreover,oxic or partially oxic niches are formed due to the diffusion of oxy-gen in upper few millimeters of ?ooded water,leaving the bulk soil anoxic.In planted soil the rice aerenchymatous tissues are also responsible for the leakage of oxygen creating an oxic rhizosphere within the anoxic bulk soil (Revsbech et al.,1999).The existence of oxic and anoxic microhabitats provides a favorable environment for nitri?cation and denitri?cation in rice paddy ?eld soils (Revsbech et al.,1999).Hence,oxygen and carbon-releasing aerenchymatous rice plants may affect the composition of the ammonia oxidizer (AOA and AOB)and denitrifying bacterial communities in water-logged paddy soil.Ammonia oxidizer and denitri?er communities are widely recognized as models for ecology studies and are intrin-sically linked to agroecosystem functioning such as the nitrogen global cycling and N 2O emission (Kowalchuk and Stephen,2001;Philippot and Hallin,2005).Ammonia oxidization to nitrite is the initial and rate limiting step in nitri?cation which is carried out by AOB (Jackson et al.,2008;Malchair et al.,2010)and/or AOA (Nicol and Schleper,2006;Wuchter et al.,2006).Denitrifying bacteria are a crucial group of microbes involved in denitri?cation and respon-sible for nitrogen losses as well as N 2O emission from agricultural systems (Philippot et al.,2007).Therefore,in depth knowledge of the abundance and dynamics of ammonia-oxidizing prokaryotes
0929-1393/$–see front matter ? 2011 Elsevier B.V. All rights reserved.doi:10.1016/j.apsoil.2011.03.004
Q.Hussain et al./Applied Soil Ecology48 (2011) 210–218211
and denitrifying bacteria in the rhizosphere of rice paddy soils is essential for understanding the functioning of rice ecosystem and predicting the impact of prevailing plant and soil condi-tions.The ammonia monooxygenase?-subunit(amoA)and copper nitrite reductase(nirK)genes have been used as functional mark-ers for cultivation independent studies of the ammonia-oxidizing prokaryotes(Cavagnaro et al.,2008;Nguan et al.,2009)and deni-trifying bacteria(Lardy et al.,2010;Smith et al.,2010),respectively. While recent studies have provided insight into the relative preva-lence of AOA and AOB in rice paddy(Chen et al.,2008;Wang et al.,2009),the knowledge is still limited on the dynamics of the individual functional groups of ammonia-oxidizing archaea(AOA), ammonia-oxidizing bacteria(AOB)and denitrifying bacteria in the rhizosphere with rice growing stages under?eld conditions.
PCR-denaturing gradient gel electrophoresis(DGGE)is a culture independent?ngerprinting technique used to monitor the spatial and temporal changes in microbial communities and the dominant microbial species within a sample(Liu et al.,2008).Qualitative DGGE analysis in combination with quantitative real-time PCR (qPCR)is capable to provide a deep insight into soil microbial com-munity dynamics(Ahn et al.,2009).Real-time PCR is considered as a?exible,simple and rapid promising tool for the quanti?cation of soil microbial communities though it may have some impor-tant limitations,including DNA extraction bias,judicious primer design,heterogeneity in ribosomal operon number,the availability of sequence data,and adequate preparation of inhibitor-free target DNA(Fierer et al.,2005).
The objectives of this study were(I)to evaluate the temporal prevalence of AOA,AOB and denitrifying bacterial communities in the rhizosphere of rice plant,(II)to investigate the relative abundances of AOA to AOB and denitrifying bacteria to ammonia oxidizer(AOA+AOB)over a period of rice plant growth,and(III)to compare the ammonia oxidizer and denitri?er community struc-tures in bulk and rhizosphere soil of rice plant.The community structures and abundances of ammonia-oxidizing prokaryotes and denitrifying bacteria were characterized by PCR-DGGE and qPCR of functional gene amoA and nirK targets,respectively.
2.Materials and methods
2.1.Site description and experiment layout
The experiment was carried out on a rice farm located in Yifeng village,Yixing Municipality,Jiangsu Province,China(31?24.26 N, 119?41.36 E).Derived from lacustrine deposit,the soil was a typ-ical high-yielding paddy soil classi?ed as a hydroagric Stagnic Anthrosols(Gong,1999)and an entic Halpudept(Soil Survey Staff,1994).A subtropical monsoon climate prevailed in the area with mean annual temperature and precipitation of15.7?C and 1177mm,respectively.The basic properties of the studied top-soil are as follows:pH(H2O)6.7,CEC18.05cmol kg?1,bulk density 1.1g cm?3,total organic carbon20.2g kg?1and total N2.99g kg?1, and available N276.1mg kg?1.For experiment,one month old rice (Oriza sativa)seedlings of Wugeng13cultivar were transplanted at a plant density of20plants/m2in a randomly selected plot of 4m×5m in area.The experiment used a randomized block design with three replicate plots.No chemicals were applied for plant protection and the plots were weeded by hand.Calcium biphos-phate,KCl and urea were applied as basal fertilizers at a rate of 125kg P2O5ha?1,125kg K2O ha?1and120kg N ha?1,respectively. The water regime was managed using an alternating?ooding and drainage cycle through the whole growing season.Soil samples were collected at different rice growing stages:before plantation (S0,just before paddy water logging and fertilizer application),45 days after planting(S1,tillering stage,?ooded condition),81days after planting(S2,grain?lling stage,wet condition)and107days after planting(S3,ripening stage,moist condition).Unplanted bulk soil,S0,was used as the control for the effect of the plant rhizo-sphere on microbial communities.
2.2.Soil sampling
For sampling of the rhizosphere soil,ten rice plants with root–soil systems were randomly excavated10cm deep from the same replicate plot at each growth stage.Following Butler et al. (2003)and Liu et al.(2008),the soil separated gently by hand from root–soil systems of the ten excavated plants was considered as bulk soil(non-rhizosphere soil).The remaining about1cm thick soils tightly attached to the root system was used as rhizosphere soil,which was carefully removed from the roots with a probe and forceps.The rhizosphere and bulk soil samples separated from ten plants of a single replicate plot were then pooled to form a composite sample,respectively.Soil samples were sieved(<2mm) immediately after collection and stored at?20?C(not more than one week)for DNA extraction.For comparative purposes,the sam-pling depth was the same throughout the rice growing stages.All soil samples were taken at same time(9:30AM)on each sampling day to limit diurnal effects.
2.3.Physico-chemical analysis
All physico-chemical properties of the soil were analyzed according to the protocols described by Lu(2000).Soil organic carbon and total nitrogen(TN)of dried samples were measured using a CNS Macro Elemental Analyzer(Elementar Analysen System GmbH,Germany)after treatment with HCl(10%,v/v)to remove car-bonates if any in the samples.The moisture content of the samples was determined by oven-drying at105?C for24h.Soil pH(H2O) was measured by Mettler–Toledo pH meter with a soil:water ratio of1:2.5.Cation exchange capacity(CEC)was measured with the ammonium acetate(1mol L?1,pH7)leaching method.
2.4.DNA extraction and real time PCR assay
Three DNA extractions from each soil sample of a single repli-cated?eld plot were performed.Each DNA extraction was made from0.5g soil using a PowerSoil TM DNA Isolation Kit(Mo Bio Lab-oratories Inc.,CA)following the manufacturer’s instructions.The three DNA extracts of the same soil sample of a single replicated plot were then pooled for analysis.The copy numbers of amoA (AOA),amoA(AOB)and nirK genes in all soil samples were deter-mined in triplicate using an iCycler IQ5Thermocycler(Bio-Rad, Hercules,CA).The quanti?cation was based on the?uorescent dye SYBR-green1,which binds to double stranded DNA during PCR ampli?cation.Primers and the thermal cycling conditions are men-tioned in Table1.The DNA concentration of all soil samples was measured at260nm using a UV Spectrophotometer(Bio Photome-ter,Eppendorf,Germany)and then adjusted to10ng?l?1.Each reaction was performed in a25?l volume containing10ng of DNA, 0.2mg ml?1BSA,0.2?M of each primer and12.5?l of SYBR premix EX Taq TM(Takara Shuzo,Shinga,Japan).Melting curve analy-sis of the PCR products was conducted following each assay to con?rm that the?uorescence signal originated from speci?c PCR products and not from primer–dimers or other artifacts.PCR prod-ucts were checked for correct size by comparison to a standardized molecular weight ladder by electrophoresis on1.5%agarose gel.A plasmid standard containing the target region was generated for each primer set(AOA,AOB and denitrifying bacteria)using total DNA extracted from the soil samples.The ampli?ed PCR products of amoA(AOA),amoA(AOB)and nirK genes were puri?ed using PCR solution puri?cation kit(Takara),ligated into p-GEM T easy vec-
212Q.Hussain et al./Applied Soil Ecology48 (2011) 210–218
Table1
Primer sets and thermal pro?les used for the absolute quanti?cation of functional target genes involved in nitrogen turnover.
Target gene Primer set Size Thermal cycling pro?le Reference
amoA(AOB)amoA-1F
amoA-2R 490bp94?C(10min);40cycles of94?C(30s),53?C(60s),
and72?C(60s).Data acquisition temperature at83?C
McTavish et al.
(1993)
amoA(AOA)Arch-amoA F
Arch-amoA R 635bp94?C(10min);40cycles of94?C(30s),53?C(30s),
and72?C(45s).Data acquisition temperature at83?C
Francis et al.
(2005)
nirK nirK876
nirK1040165bp95?C(10min);40cycles of94?C(30s),58?C(60s),
and72?C(60s).Data acquisition temperature at80?C
Henry et al.
(2004)
AOB:ammonia oxidizing bacteria;AOA:ammonia oxidizing archaea.
tor(Promega,Madison,WI)and cloned into Escherichia coli DH5?. Clones containing correct inserts were chosen as the standards for real-time PCR(qPCR).Plasmid DNA was isolated using plasmid extraction kit(Takara)and DNA concentrations were determined by spectrophotometer as mentioned above.As the size of the vector and PCR inserts were known,the copy numbers of amoA genes(AOA and AOB)and nirK gene were directly calculated from the concen-tration of extracted plasmid DNA.Standard curves were generated using triplicate10-fold dilutions of plasmid DNA ranging from 1.35×102to1.35×108copies for amoA(AOA)gene,1.03×102to 1.03×108copies for amoA(AOB)gene and4.89×102to4.89×108 copies of template for nirK gene per assay.High ampli?cation ef?-ciencies of99%(AOA),109%(AOB)and nirK(93%)were obtained using the slopes?3.35,?3.11and?3.51of standard curve,respec-tively.
2.5.PCR-DGGE ammonia oxidizers and denitrifying bacterial community analysis
Total extracted DNA of each soil sample was ampli?ed with the Arach-amoA F-GC and Arach-amoA R primer set speci?c for AOA (Francis et al.,2005),the amoA-1F-GC and amoA-2R set speci?c for the AOB(McTavish et al.,1993)and the nirK876-GC and nirK1040 set for the denitrifying bacterial communities(Henry et al.,2004). The GC clamp(5 -CCGCCGCGCGGCGGGCGGGGCGGGGGCACGGGG-3 )described by Muyzer et al.(1997)was added to5 end of primer to stabilize the melting behaviour of the DNA fragments.PCR reac-tion was performed in an Eppendorf Autothermer Cycler(Bio-Rad, USA)using25?l reaction volume.The reaction mixture contained 12.5?l Go Taq?Green Master Mix(Promega,Madison,WI),1?l of 20?M of each primer,and1?l of DNA template.For DGGE analy-sis,PCR products were separated on8%(w/v)polyacrylamide gels (acrylamide–bisacrylamide[37.5:1])containing denaturing gradi-ents of45–65%for AOA,45–70%for AOB and35–65%for nirK using the Bio-Rad D-Code universal mutation detection system.A100% denaturant was de?ned as8%acrylamide containing7M urea and 40%deionized formamide.DGGE was performed using20?l of the PCR product in1×TAE buffer at60?C,200V for5min,then150V for7h(AOA and AOB)and110V for12h(nirK).Gels were silver stained(Sanguinetti et al.,1994)and scanned with gel document system(Bio-Rad,USA).
2.6.Sequencing and phylogenetic analysis
Some bands from DGGE gel of AOA,AOB and denitrifying com-munities were detected and numbered on the basis of their relative intensity or speci?c positions across all treatments.The num-bered bands with same mobility in the different lanes of DGGE gel of each gene were excised in triplicates.The excised bands were left to diffuse passively for24h at4?C in30?l sterilized dd H2O to elute the DNA.2?l of recovered DNA was used as template for the PCR ampli?cation under the same conditions as described above.The PCR ampli?ed products were subjected to DGGE again to con?rm their identity and ensure that all retrieved DGGE bands are single bands.The con?rmed bands were fur-ther re-ampli?ed and cloned to E.coli described as above in qPCR assay section and white colonies were selected for sequencing. After sequencing,we found that bands with same mobilities in the DGGE gel of each gene had same sequences.Therefore we used one sequence of each numbered band for phylogenetic anal-ysis.Sequences retrieved from the DGGE pro?les of amoA(AOA and AOB)and nirK genes were compared with GenBank data base sequences using BLAST(Basic Local Alignment Search Tool) (http://www.ncbi.nlm.nih/gov/blast/)to search for best matches. The sequences of DGGE bands have been deposited in GenBank under the accession numbers HQ012641–HQ012645amoA(AOA), HQ020334–020341amoA(AOB)and HQ012630–HQ012634(nirK).
2.7.DGGE pro?le analysis
DGGE pro?les of amoA(AOA and AOB)and nirK genes of all three replicate plots revealed highly reproducible results for each treat-ment(data not shown);therefore,the results for only one replicate are shown in the DGGE patterns(Figs.3–5).However,principal component analyses(PCA)of DGGE pro?les have been made on three replicates to elucidate the microbial community structures based on relative band intensity and positions.Digitized DGGE images were analyzed with Quantity One image analysis software (Version4.0,Bio-Rad,USA).This software identi?es the bands with the same position in the different lanes of the gel and also measures the intensity of identi?ed bands.
2.8.Data processing and statistical analysis
A non-parametric analysis(Kruskal–Wallis)was performed to test the overall effect of plant growth stages on gene abundances. The use of this statistical method was justi?ed by the small sample size and by the heterogeneity of the data.The Dunn procedure was used as post hoc test to check the differences between growing stages of rice plant(P<0.05)using Minitab v.15.
3.Results
3.1.Ammonia oxidizers(AOA and AOB)abundance and relative AOA:AOB ratios
The copy numbers of amoA(AOA)gene in the paddy soil,ranging from1.2×106to4.5×106g?1dry weight of soil,were greater than those of amoA(AOB)gene,ranging5.5×105to3.1×106g?1dry weight of soil,during all growing stages(Fig.1).The AOB abundance in the rhizosphere varied signi?cantly in response to rice grow-ing stages(Kruskal–Wallis test,P<0.05)while the AOA abundance in rhizosphere and bulk soil was unchanged over all rice growing stages(Kruskal–Wallis test,P>0.05).Population size of AOA and AOB increased in the rhizosphere soon after the rice transplanting with the maximum abundances recorded at the grain?lling stage (S2).Compared to bulk soil,archaeal amoA gene and bacterial amoA gene abundances in rhizosphere were1.7,3.3and2.5,and2.6,4.8 and4.6times higher respectively at S1,S2and S3stages.The rela-tive AOA:AOB ratios ranged from1.46to3.8for overall soil samples,
Q.Hussain et al./Applied Soil Ecology 48 (2011) 210–218213
123
45(a m o A g e n e c o p i e s g -1 d r y s o i l × 106
)
AOA
AOB Fig.1.Abundance of AOA (white)and AOB (shaded)amoA gene in rhizosphere (R)and bulk (B)soil at four rice growing stages (unplanted soil,S0;tillering,S1;grain?lling,S2;ripening,S3).Ratios of AOA to AOB amoA copies are shown in bold at top of columns with each treatment.Different capital letters indicate statistically signi?cant differences among the rice growing stages for AOA (n =3;error bars are ±SD).Different small letters indicate statistically signi?cant differences among rice growing stages for AOB (n =3;error bars are ±SD).
showing the predominance of AOA throughout the period of rice growth (Fig.1).
3.2.Denitrifying bacterial (nirK)abundance and relative nirK:amoA (AOA +AOB)ratios
The denitri?er nirK gene abundance in the rhizosphere varied signi?cantly with rice growing stages (Kruskal–Wallis test,P <0.05)while copy numbers of nirK gene in the paddy soil ranged from 2.4×107to 6.1×107g ?1dry weight of soil (Fig.2).The nirK gene abundance was 2.6,2.0and 1.9times higher in the rhizosphere than that of the unplanted soil (S0)at S1,S2and S3growth stages,respectively.The nirK gene abundance was signi?cantly higher in the rhizosphere at S1compared to S2,however no signi?cant differ-ence was observed between S2and S3.The nirK gene copy numbers of the rhizosphere were 1.8,1.9and 2.1times higher compared to corresponding bulk soil at S1,S2and S3growth stages.The relative nirK :amoA (AOA +AOB)ratios ranged from 6.0to 13.9for overall soil samples,indicating that denitrifying bacterial populations were dominant relative to ammonia oxidizers in the paddy soil (Fig.2).The denitrifying bacterial (nirK )abundance relative to ammonia
oxidizers (amoA )decreased signi?cantly in rhizosphere at repro-ductive stages (grain ?lling and ripening)compared to vegetative stage of tillering.
3.3.Ammonia oxidizer (amoA)and denitrifying bacterial (nirK)communities structures
Principal component analysis (PCA)of DGGE pro?les of AOA and AOB in rhizosphere and bulk soil at all growth stages (S1,S2and S3)gave good summaries of data,as 74.2%(AOA)and 78.7%(AOB)of the total variability was explained by the ?rst two compo-nents (Figs.3A1and 4B1).PCA of AOA and AOB clearly showed that the unplanted soil (S0)was distinct from the other plant growth stages (S1,S2and S3).AOA community pro?les of rhizosphere and bulk soil were indistinguishable among all growth stages,whereas the AOB patterns of the vegetative stage (tillering stage)were well separated from reproductive stage (grain ?lling and ripen-ing).Moreover,both rhizosphere and bulk soil showed no distinct separation in the grain?lling and ripening stages.
PCA of DGGE pro?le further elucidated differences in denitri-fying bacterial (nirK )community structure between
rhizosphere
20
40
60
80
( g e n e c o p i e s g -1
d r y s o i l × 106
)
nirK amoA (AOA+AOB)
Fig.2.Abundance of nirK gene (white)and amoA (AOA +AOB)gene in rhizosphere (R)and bulk (B)soil at four rice growing stages (unplanted soil,S0;tillering,S1;grain?lling,S2;ripening,S3).Ratios of nirK to amoA (AOA +AOB)copies are shown in bold at top of columns with each treatment.Different capital letters indicate statistically signi?cant differences among the rice growing stages for amoA gene (n =3;error bars are ±SD).Different small letters indicate statistically signi?cant differences among rice growing stages for nirK gene (n =3;error bars are ±SD).
214Q.Hussain et al./Applied Soil Ecology
48 (2011) 210–218
Fig.3.DGGE pro?les(A)and principal component analysis(A1)of archaeal-amoA gene fragments from rhizosphere(R)and bulk(B)soil at S0(no plant,NP),S1(tiller-ing),S2(grain?lling)and S3(ripening)stages.M:100bp ladder marker.Arrows indicate the excised bands(A1–A5)for sequencing on the basis of their relative intensity or speci?c positions over a course of plant growth.Similar symbols with same color in PCA plot indicate the replicate samples.
and bulk soil at the growth stages(Fig.5N1).The?rst two principal components(PC1and PC2)could explain76.3%of the total variance for soil denitrifying bacterial community structures in rice paddy over all growing periods.The denitrifying community structures of the rhizosphere at ripening stage(R3)showed clearly divergence from the pro?les generated for the corresponding bulk soil.More-over,the denitrifying community structures of the unplanted soil (S0)were well separated from the rhizosphere and bulk soils of all growth stages(Fig.5N1).Denitrifying bacterial community struc-tures in the rhizosphere and the corresponding bulk soil at tillering stage(S1)were close to grain?lling(S2)but well separated from ripening stage(S3).
3.4.Phylogenetic analysis
Some speci?c bands of amoA(AOA and AOB)and nirK genes in DGGE pro?les were selected and numbered(A1–A5,B1–B8and N1–N5)on the basis of their relative intensity and positions across all treatments(Figs.3–5).Although some bands were present in the pro?les sampled at all growing stages,their intensity varied among treatments.The DGGE pro?le of AOA,AOB and nirK revealed that bands A1,A2,A3,A4,B1and B8were present in all grow-ing stages except the unplanted(S0),while A5,B5,B6,N1and
N4Fig.4.DGGE pro?les(B)and principal component analysis(B1)of bacterial-amoA gene fragments from rhizosphere(R)and bulk(B)soil at S0(no plant,NP),S1(tiller-ing),S2(grain?lling)and S3(ripening)stages.M:100bp ladder marker.Arrows indicate the excised bands(B1–B8)for sequencing on the basis of their relative intensity or speci?c positions over a course of plant growth.Similar symbols with same color in PCA plot indicate the replicate samples.
were found in the pro?les of all the soil samples.The intensity of band B3was strong in S1,while slight in other stages(S2and S3). The band N3was detected at all sampling time periods except S1. The band N5was present in all samples;however the intensity of band N5became strong with the development of plant at S3.The obtained sequences were subjected to BLAST search in the Gen-Bank database,which con?rmed that all sequenced clones of DGGE pro?le represented amoA(AOA and AOB)and nirK like sequences (Table2).The BLAST analysis of the amoA(AOA)sequences obtained from DGGE gel bands showed high similarity(>97%)with uncul-tured Crenarchaeote and majority of those belonged to rice paddy soil.All gene sequences retrieved from our DGGE pro?le of amoA (AOB)were related to the class of‘?-proteobacteria’.Most of amoA (AOB)sequences had the highest similarity(>97%)database hits to the uncultured AOB bacteria,isolated from soils and river sed-iments,af?liated with Nitrosospira or Nitrosospira-like sequences. Moreover,all sequences of denitrifying bacterial nirK showed their best matches(>82%)in the NCBI(National Center for Biotechnology Information)GenBank database with different uncultured strains from soil source(Table2).
4.Discussions
4.1.Rhizosphere effect on microbial communities involved in N turnover
A major focus in microbial ecology is to understand whether and how microbial communities in ecosystems interact.
Q.Hussain et al./Applied Soil Ecology48 (2011) 210–218215
Table2
Nucleotide sequence BLAST results of DGGE amplicons generated using amoA(AOA),amoA(AOB)and nirK genes speci?c primers.
Representative sequence Close NCBI blast match
Band Accession number Species name Accession number Similarity(%)
Ammonia oxidizing archaea(amoA gene)
A1HQ012641Uncultured Crenarchaeote a rice soil FN56252199
A2HQ012642Uncultured Crenarchaeote a rice soil FN56253199
A3HQ012643Uncultured Crenarchaeote a rice soil FN56251899
A4HQ012644Uncultured Crenarchaeote a rice soil FN56252299
A5HQ012645Uncultured Crenarchaeote a unfertilized red soil EF20721497
Ammonia oxidizing bacteria(amoA gene)
B1HQ020334Uncultured beta proteobacterium a soil aggregate fractions DQ48079399
B2HQ020335Nitrosospira sp.CT2F a Cascade Mountains AY18914399
B3HQ020336Uncultured beta proteobacterium a river sediment FJ15880999
B4HQ020337Uncultured beta proteobacterium a river sediment FJ15876999
B5HQ020338Uncultured beta proteobacterium a rice rhizosphere soil GU37731299
B6HQ020339Uncultured beta proteobacterium a red soil EU79080797
B7HQ020340Uncultured beta proteobacterium a red soil EU79080798
B8HQ020341Uncultured beta proteobacterium a river sediment FJ15880498 Denitrifying bacteria(nirK gene)
N1HQ012630Uncultured bacterium a rice?eld soil AB45366098
N2HQ012631Uncultured bacterium a soils AY67550192
N3HQ012632Uncultured bacterium a soil from agricultural plots DQ78334582
N4HQ012633Uncultured bacterium a red soil GU27052994
N5HQ012634Uncultured bacterium a soils AY675477100
a Isolated source/habitat;NCBI:National Center for Biotechnology Information;BLAST:Basic Local Alignment Search
Tool.
Fig.5.DGGE pro?les(N)and principal component analysis(N1)of denitrifying bacterial-nirK gene fragments rhizosphere(R)and bulk(B)soil at S0(no plant,NP), S1(tillering),S2(grain?lling)and S3(ripening)stages.M:100bp ladder marker. Arrows indicate the excised bands(N1–N5)for sequencing on the basis of their rel-ative intensity or speci?c positions over a course of plant growth.Similar symbols with same color in PCA plot indicate the replicate samples.Functional groups of microorganisms like AOA,AOB and deni-tri?ers are crucial mediators of N cycling in the rice paddy soil and can thereby affect plant growth by competing for nutrients. Therefore,the interaction between plant and rhizosphere microor-ganisms involved in N turnover is of special interest in this study. In the current study,rice plant stimulated higher AOA,AOB and denitrifying bacterial abundances in rhizosphere and structures of ammonia oxidizers(AOA and AOB)and denitrifying bacte-ria were also different between planted and unplanted soils.In fact,rice plantation may affect the physical–chemical properties and the biological parameters of the rhizosphere by continuously producing and excreting organic compounds through rhizode-position(Hinsinger et al.,2006).The quantity,composition and spectra of root exudates are considered to lead the development of plant-speci?c microbial communities in root-associated habi-tats(Kowalchuk et al.,2002).The fact that the number of amoA (AOA)gene,amoA(AOB)gene and nirK gene copies in the rhizo-sphere were signi?cantly higher than in the corresponding bulk soil at all growth stages(Figs.1and2)may be attributable to the rhizodeposition of carbohydrates from plant roots favoring micro-bial growth in comparison with that in the bulk,a phenomenon well known as‘rhizosphere effect’(Smalla et al.,2001;Dun?eld and Germida,2003).It is also well known that rice roots release oxygen through aerenchymatous tissue at rates suf?cient to sup-port aerobic microbial processes in the rhizosphere(Bedford et al., 1991).
Moreover,qPCR in combination with PCR-DGGE provided reproducible metric to monitor gross differences and changes in microbial population size and structure between rice planted and unplanted soils.
4.2.Ammonia oxidizers dynamics and relative AOA:AOB ratios in the rice rhizosphere
Recent?ndings have extended the known ammonia-oxidizing prokaryotes from the domain Bacteria to Archaea.However,in the complex rice ecosystem it remains unclear whether AOA or AOB are exclusively or predominantly linked to prevailing plant and soil conditions over a rice crop season.In line with our?ndings,Chen et al.(2008)reported that rice cultivation under microcosm exper-iment led to greater abundance of AOA relative to AOB amoA gene
216Q.Hussain et al./Applied Soil Ecology48 (2011) 210–218
copies and to differences in AOA and AOB community composi-tion.Bacterial amoA gene abundance was highest at the grain?lling stage,attributable to enhanced root exudation and high amounts of nutrients in the rhizosphere(Bürgmann et al.,2005).Wheatley et al.(2003)investigated the temporal variation of ammonia oxi-dizers in?elds with barely and bean crops using PCR-DGGE and competitive PCR and suggested that community structures and abundance of bacterial ammonia oxidizers did not vary with the time.In contrast,Hai et al.(2009)reported variation of amoA gene abundance in the rhizosphere with growing stages of sorghum cul-tivar under?eld conditions using qPCR.In accordance with the ?ndings of Chu et al.(2009),all the DGGE band sequences retrieved from our soil samples were related to uncultured AOB and af?li-ated to the genus Nitrosospira-like rather than Nitrosomonas-like. Moreover,bacterial amoA gene abundance was lower at tillering stage when waterlogged(S1)than at grain?lling(S2)and ripening stages(S3)when non-?ooded.This result indicates that soil mois-ture content and the associated soil aerobic condition may also be an important factor determining AOB abundance and dynamics in the paddy soil(Chu et al.,2009).As plant growth stage and soil water conditions may be interacted in?eld conditions,it is still uncertain which factor was more important.It is supposed that combine effect of plant developmental and soil water condition may have interactive effect on shaping the communities of AOB in paddy soil.In contrast to AOB,the community structures and abundance of AOA were not affected by rice growing stages,show-ing that AOA are more stable and do not respond as sensitively to environmental differences as their bacterial counterparts(Santoro et al.,2008).
The determination of the AOA/AOB ratio based on amoA gene copy numbers,ranging from 1.46to 3.8,indicated that AOA were predominant across whole period of rice growth(Fig.1). Several studies have con?rmed the predominance of AOA over AOB in various environments such as marine sediments(Francis et al.,2005),ocean water(Wuchter et al.,2006),upland soil (He et al.,2007)and particularly in the rhizosphere of rice pad-dies(Chen et al.,2008).Assuming 2.5amoA gene copies per AOB cell and1amoA gene copy per AOA cell(Leininger et al., 2006),the AOA/AOB ratio on a cell-based calculation was in the range of2.9–10.3(data not shown)of rhizosphere and bulk soil throughout the growing stages of the rice plant.This?nd-ing is in general agreement with recent report by Hai et al. (2009),who obtained cell-based AOA/AOB ratios from 5.9to 19.7.As AOA always dominated the ammonia-oxidizers com-munity in the rhizosphere of rice paddy,AOA seems better adapted than AOB to microaerophilic environment in the rhi-zosphere(Bodelier et al.,1996)or may take bene?ts from root exudates,as reported for terrestrial Crenarchaeota(Simon et al., 2005).
4.3.Denitrifying bacterial community dynamics and relative
nirK:amoA(AOA+AOB)ratio in the rice rhizosphere
Denitri?cation is one of the major nitrogen transformation pro-cesses in rice paddy?elds due to the anaerobic conditions in soil and considerable amounts of N2O emissions occur during the dry phase of the dry–wet cycles(Yan et al.,2000).Denitrifying bac-teria harboring the functional genes(nirK and nirS)that encode the enzyme nitrite reductase are responsible for key denitri?ca-tion steps(Zumft,1997).This study was focused on the analysis of nirK-type denitri?ers only,because in several previous studies nirK relative to nirS could be more readily ampli?ed from sorghum rhizosphere(Sharma et al.,2005),arable soil(Wolsing and Prieme, 2004)and particularly from rice paddy where nirK gene was ten times abundant than nirS(Yoshida et al.,2009).Denitrifying genes contain only single copy per genome except the narG gene,which can be present in up to three copies(Jones et al.,2008).The number of nirK gene copies per gram of soil also revealed population size of around2.4×107to6.1×107g?1in our paddy soil samples,which are within the range of those reported by Henry et al.(2004).In the work by Sharma et al.(2005),the introduction of plant in?uenced the diversity and composition of nirK-type denitri?ers in the rhi-zosphere of three legume crops(Sharma et al.,2005).Our results are congruent with the observations of Chèneby et al.(2004),who revealed a difference in the denitri?er community structures in soil planted with maize compared to unplanted soil.Apart from effects induced by plants,Wolsing and Prieme(2004)reported that the community composition of denitrifying bacteria was also in?uenced by the temporal variation of plant and soil conditions. They observed a signi?cant seasonal variation in the structure of nirK denitrifying community over8-month period in an arable soil. Based on DGGE analysis,Wertz et al.(2009)found that the com-position of the nirK-type denitri?er community changed over the growing season and among spatial locations in the potato crop ?eld.In line with their?ndings,all of the DGGE clone sequences in this study were more similar to other nirK sequences retrieved from uncultured soil bacteria than from known denitrifying iso-lates(Table2).Similarly,Yoshida et al.(2009)also showed that functional diversity and quantity of denitrifying nirK gene changed over the time in rice paddy?eld soil using qPCR and gene clone libraries.
Furthermore,the nirK denitri?ers were higher in the rhizo-sphere soil collected at S1when?ooded than at other stages(S0,S2 and S3)when non-?ooded.This may suggest that nirK-harboring denitri?ers are affected by the environmental changes such as rice paddy water logging and the redox potential dynamics(Yoshida et al.,2009).Szukics et al.(2010)also observed that denitri?er(nirK) community structure was mainly affected by the water content and nirK gene abundance rapidly increased in response to wet condi-tions.Beside the role of rice plants,irrigation water regimes during the growth season of rice plant were also important in selecting and shaping the community structure and abundance of denitrifying bacteria.
The denitri?ers-nirK gene was observed more abundant than bacterial amoA gene but less abundant compared to archaeal amoA gene in a pristine forest soil(Szukics et al.,2010).However,Hai et al.(2009)reported the predominance of nirK gene relative to amoA genes(AOA and AOB)in the rhizosphere of sorghum culti-vars.Similarly,the relative nirK:amoA ratios ranged from6.0to 13.9in the rice paddy soil(Fig.2),showing the predominance of denitri?ers(nirK)populations relative to ammonia oxidizers(AOA and AOB)in our study.
5.Conclusions
Our data clearly demonstrated the abundance and dynamics of ammonia oxidizers and denitri?ers in rhizosphere across the growing stages of rice plant.The rice cultivation led to greater abundance of ammonia oxidizers(AOA and AOB)-amoA and den-itrifying bacterial-nirK gene copies in the rhizosphere.Moreover, the community structures of AOA,AOB and denitri?ers of the rice planted soil were well distinct from unplanted https://www.wendangku.net/doc/081363651.html,munity structures and abundances in rhizosphere based on bacterial amoA and denitri?ers nirK genes responded actively and differently to plant and soil conditions over the time course of rice growth. However,community structures and population size of AOA in the rhizosphere and bulk soil remained unchanged across the rice growing stages.The measured gene abundances based on DNA does not discriminate between active and dormant populations. Therefore investigations based on the gene expression and enzyme activity remain to be performed to re?ect the metabolically active
Q.Hussain et al./Applied Soil Ecology48 (2011) 210–218217
populations involved in N turnover in soil.Furthermore,linking the N2O emission to dynamics of metabolically active nitri?er and denitri?er populations in paddy?eld may help to understand the main microbial driving factors in soil N2O emission,which deserves further work in future.
Acknowledgements
This study was funded by National Science Foundation of China under grant numbers40830528and40710019002.The?rst author is grateful to the Higher Education Commission,Pakistan for grant-ing the scholarship for his PhD study in China.
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项目管理方法和项目实施方法的关系
项目管理方法和项目实施方法的关系 在一个项目的执行过程中还同时需要两种方法：项目管理方法 和项目实施方法。 项目实施方法指的是在项目实施中为完成确定的目标如某个应 用软件的开发而采用的技术方法。项目实施方法所能适用的项目范围会更窄些，通常只能适用于某一类具有共同属性的项目。而在有的企业里，常常把项目管理方法和项目实施方法结合在一起，因为他们做的项目基本是属于同一种类型的。 实际上，只要愿意，做任何一件事情，我们都可以找到相应的 方法，项目实施也是一样。以IT行业的各种项目为例，常见的IT项目按照其属性可以分成系统集成、应用软件开发和应用软件客户化等，当然，也可以把系统集成和应用软件开发再分解成一些具备不同特性的项目。系统集成和应用软件开发的方法很显然是不一样的，比如说：系统集成的生命周期可能会分解为了解需求、确定系统组成、签订合同、购买设备、准备环境、安装设备、调试设备、验收等阶段;而应 用软件的开发可能会因为采用的方法不同而分解成不同的阶段，比如说采用传统开发方法、原型法和增量法就有所区别，传统的应用软件开发的生命周期可能分解成：了解需求、分析需求、设计、编码、测试、发布等阶段。 至于项目管理，可以分成三个阶段：起始阶段，执行阶段和结 束阶段。其中，起始阶段是为整个项目准备资源和制定各种计划，执
行阶段是监督和指导项目的实施、完善各种计划并最终完成项目的目标，而结束阶段是对项目进行总结及各种善后工作。 那么，项目管理方法和项目实施方法的关系是什么呢?简单的说，项目管理方法是为项目实施方法得到有效执行提供保障的。如果站在生命周期的角度看，项目实施的生命周期则是在项目管理的起始阶段和执行阶段，至于项目实施生命周期中的阶段分布是如何对应项目管理的这两个阶段，则视不同项目实施方法而不同。 一、实际意义 项目管理方法和项目实施方法对项目的成功都是有重要意义的，两者是相辅相成的，就如管理人员和业务技术人员对于企业经营的意义一样。从IT企业的角度看，任何一个IT企业如果要生产高质量的软件产品或者提供高质量的服务，都应该对自身的项目业务流程进行必要的分析和总结，并逐步归纳出自己的项目管理方法及项目实施方法，其中项目实施方法尤其重要，因为大部分企业都有自己的核心业务范围，其项目实施方法会比较单一，在这种情况下，项目管理方法可能会弱化，而项目实施方法会得到强化，两者会较紧密的结合在一起。只有总结出并贯彻实施符合企业自身业务的方法，项目的成功才不会严重依赖于某个人。在某种程度上，项目管理方法和项目实施方法也是企业文化的一部分。 从客户的角度看，如果希望得到有保障的产品或服务，那就既 需要关注提供产品或服务的企业是否有恰当的项目管理方法和项目 实施方法，也必须尊重该企业的项目管理措施与方法。
土地开发整理分类介绍
根据土地开发整理内容的不同，土地开发整理可分为三种类型：土地整理、土地复垦、土地开发。 （一）土地整理土地整理是指在一定区域内，按照土地利用总体规划、土地开发整理专项规划确定的目标和用途，通过采取行政、经济、法律和工程技术手段，对土地利用状况进行调整、改造、综合整治，提高土地利用率，改善生产、生活条件和生态环境。 根据土地整理后的主导用途，可将土地整理分为农用地整理和建设用地整理。 1、农用地整理农用地整理是指在一定区域内，依据土地利用总体规划及有关专项规划，采取行政、经济、法律和工程技术措施，对田、水、路、林、村等进行综合整治，以调整土地关系，改善土地利用结构和生产、生活条件，增加土地有效供给量，提高农用地质量，提高土地利用率和产出率的过程。农用地整理包括农用地调整、农用地改造、地块规整、基础设施配套、零星农宅的迁并等，具体内容包括农用地面积、位置的变动、性质的置换、低效农用地的改造以及地块规整重划，水、电、路等小型基础设施配套和零星农宅的迁出或合并。农用地整理可根据整理后的主导用途分为耕地整理、园地整理、林地整理、牧草地整理和养殖水面整理等。（1）耕地整理。耕地整理是指对农田进行的整理。耕地整理的主要工程内容包括：土地平整工程、农田水利工程、田间道路工程、其他工程（如农田防护林工程、生态环境保护工程等）。（2）园地整理。园地整理主要指果园、桑园、橡胶园和其他经济园林用地的
整理。（3）林地整理。林地整理包括防护林、用材林、经济林、薪炭林、特种林地的整理。（4）牧草地整理。牧草地整理包括放牧地整理和割草地整理。（5）养殖水面用地整理。养殖水面用地整理主要指人工水产养殖用地整理。 2、建设用地整理建设用地整理是以提高土地集约利用为主要目的，采取一定措施和手段，对利用率不高的建设用地进行综合整理。建设用地整理包括村镇用地、城镇用地、独立工矿用地、交通用地和水利设施用地以及其他建设用地的整理。 （1）村镇用地整理。村镇用地整理包括村镇的撤并、撤迁和就地改扩建。 （2）城镇用地整理。城镇用地整理主要指城镇建成区内的存量土地的挖潜利用、旧城改造、用途调整和零星闲散地的利用。 （3）独立工矿用地整理。独立工矿用地整理主要指就地开采、现场作业的工矿企业和相配套的小型居住区用地的布局调整、用地范围的确定和发展用地选择，一般不包括大规模废弃地复垦。（4）基础设施用地整理。基础设施用地整理包括公路、铁路、河道、电网、农村道路、排灌渠道的改线、裁弯取直、疏挖和厂站的配置、堤坝的调整，也包括少量废弃的路基、沟渠等的恢复利用。 （二）土地复垦土地复垦是指对生产建设过程中因挖损、塌陷、压占等造成破坏而废弃的土地，采取一定措施，使其恢复到可利用的状况。土地复垦包括工矿企业在生产建设过程中挖损、塌陷、压占等造成
数字化校园建设与管理办法
数字化校园建设与管理办法 第一章总则 第一条为加强学校数字化校园的建设和管理，规范数字化校园建设各项工作，提高学校信息化应用水平，保证信息化建设的实效性与可持续发展，实现学校信息资源和软硬件资源的有机集成和共享，充分发挥信息化建设成果在人才培养、科学研究、社会服务和文化传承创新等方面的支撑作用，根据相关的法律法规、国家和教育部对教育信息化建设的指导意见，以及《教育信息化十年发展规划2011—2020》、《陕西省教育信息化十年(2011—2020年)发展规划》、《陕西省教育信息化建设三年行动计划》等有关精神，特制定本办法。 第二条学校数字化校园建设，在学校信息化建设领导小组的领导下，由教务处信息中心统一规划、统一审批、统一建设、统一管理，并按照整体规划、分步实施的原则，以应用为中心，以数字资源建设为重点，逐步达到为师生、领导和管理部门提供良好的服务和辅助决策的建设目标，提升学校的综合竞争力。 第三条本办法适用于全校范围内各部门所拥有或负责管理运行的与数字化校园相关的基础网络、信息化公共平台、数字教育资源、管理信息系统、网站、数字监控网络及其相关网络接入设备、服务器、大容量存储设备等的建设和管理。 第二章管理机构与工作职责 第四条信息化建设领导小组是全面推进学校数字化校园建设的
最高管理与决策机构，负责审议学校数字化校园建设发展的中长期规划与经费预算；负责审议学校数字化校园建设、运维管理及校园网安全规章制度；明确学校数字化校园建设中各部门的责任分工、资源分配以及考核机制；对学校数字化校园建设中的重大问题和政策性问题进行决策。 第五条学校信息化建设领导小组负责对学校教育信息化建设发展的中长期规划进行论证，对数字化校园提出意见和建议；对学校数字化校园建设发展战略、政策、规划和发展中的重大问题提出建议和咨询意见；对学校数字化校园建设进程中各子项目的建设与验收提供技术层面与应用层面的意见或建议；指导学校数字化校园建设和信息化教育新模式的探索和研究工作。 第六条信息中心是学校数字化校园建设与管理具体实施的主体部门，全面负责学校数字化校园建设和管理工作。负责制定学校数字化校园建设发展的中长期规划与经费预算，制定学校数字化校园建设、运行与管理及保障校园网安全的规章制度；负责组织、实施学校数字化校园各项建设工作；负责对学校数字化校园建设相关项目和各部门申报的信息化新建和改造项目进行审核和实施；负责学校信息编码规范和数据标准的制定；负责学校信息资源共享、信息资源整合和系统集成；为各部门信息化建设提供技术指导、支持、监督和评比；负责公共平台应用的推广与培训；负责健全和完善信息化工作管理体系。 第七条各部门信息管理员负责本部门信息化相关数据的收集、整理和上报，负责本部门网站信息的更新、备份和维护；网络协管员
软件开发
《软件开发工具》串讲笔记 一、绪论 1、简述软件开发工具的范围？在高级程序设计语言的基础上，为提高软件开发的质量和效率，从规划、分析、设计、测试、成文和管理各方面，对软件开发者提供各种不同程序帮助的一类新型软件。 2、简术用通用软件辅助软件开发的缺点？有许多工作是通用软件所无法完成的；用通用软件完成某些工作，只能表现出其表面的形式，而不能反映其逻辑内涵，只能做到“形似”，不能做到“神似”；难于保持一致性。 3、简述集成化软件开发工具产生的背景？集成的软件开发工具称为软件开发环境，是指包括支持全过程、全阶段的软件开发工具。以往的专用软件开发工具对软件的开发缺乏全面的、统一的支撑环境。这些零散地、分散地支持各个工作阶段、各项具体工作的专用工具之间没有有机地联系起来，必然会造成冲突与矛盾。这种冲突与矛盾对于用户来说，造成了沉重的负担，使用工具越多这种负担越重，以致抵消了工具带来的益处。这种情况导致了集成化软件开发工具的产生。 4、简述第四代语言与软件开发工具的区别？软件开发工具包括4GL的功能；软件开发工具支持系统分析、设计工作；软件开发工具支持文档工作。 5、简述软件开发总体设计阶段的工作要点？是根据软件功能说明书的要求，完成软件的总体设计，包括整个软件的结构设计、公用的数据文件或数据库的设计、各部分的连接方式及信息交换的标准等。 6、简述软件开发实现阶段的工作，以及应强调之点。包括程序的编写和文档的编写，应特别强调组织与协调，及时发现并纠正背离总体设计要求的情况。 7、简述软件开发工具认识与描述客观系统的功能要求？认识与描述客观系统是软件开发第一阶段所需的重要工作。该项工作不确定程度高，更需要经验，更难规范化，需要对复杂系统认识与理解，并在此基础上抽象出信息需求与信息流程。 8、简述软件开发的项目管理功能？为项目管理人员提供支持。项目管理包括进度管理、资源与费用管理、质量管理三个基本内容。还包括需要提出测试方案，提供测试环境和测试数据，并进行版本管理。 9、从人类科学技术发展的角度论述软件的意义？软件是广大使用者与计算机之间的桥梁，软件是人类在各个领域中积累的知识结晶，软件是使人类文明与知识得以延续的新的载体，软件是人类进一步成为一个整体、得以进一步相互联系的纽带。 10、论述第一代到第四代程序设计语言的主要特征？第一代程序设计语言就是计算机的指令系统。用户用机器指令编写程序。这种程序就是机器指令的序列，由“0”和“1”组成，难于阅读，难于维护，而且程序高度依赖于计算机硬件，难于移植。第二代语言是汇编语言，其中每个语句是用助记符动工表示的机器指令。虽然可读性和可移植性方面前进了一步，但依然依赖于计算机硬件。第三代语言也称为高级程序设计语言，其中的语句与机器指令并不一一对应，尤其是表达式的书写与人们的习惯基本相同。程序员需要逐行编写语句来实现算法的过程，因此，它属于过程化的语言。第四代语言是非过程化的程序设计语言，用户只说明要求做什么，而把具体的执行步骤交由软件自动执行。 11、说明软件开发工具和新的软件开发方法的主要特点？自动化程序提高；软件开发工作包括了需求分析；软件开发工作包括了项目管理和版本管理；吸收了许多管理科学的内容和方法。 12、说明软件产品开发过程各个阶段的主要任务。需求分析阶段：根据用户的初始要求形成严格的、明确的、可供实际开发使用的功能说明书；总体设计阶段：根据软件功能说明书的要求，完成软件的总体设计；实现阶段：程序的编写和文档的编写；测试阶段：测试软件是
数字化校园建设方案.doc
天津市东丽区职业教育中心学校“数字校园实验校”建设实施方案 一、信息化发展战略定位和愿景 根据学校十三五战略发展规划，在国家级示范校的基础上，立足东丽，面向天津，辐射全国，走向世界，实现“工学结合高要求、专业建设高品位、教育教 学高质量、就业服务高水平、学校发展高效益”的五高目标，“十三五”末期实现学校向世界一流水平的跨越，充分发挥示范和辐射作用。通过本期数字化校园项目建设，将我校打造成全国一流的中职数字化校园，构建技术先进、扩展性强、安全可靠、高速畅通、覆盖全校的校园网络环境。 建立一整套校园信息管理系统，为实现“环境数字化、管理数字化、教学数 字化、产学研数字化、学习数字化、生活数字化”提供全面的系统支持，使之成 为一个全面、集成、开放、安全的信息系统，成为一个网络化、数字化、智能化、虚拟化的新型教育、学习、实训和管理平台。通过数字化校园项目建设，推动教学模式变革，提高人才培养质量，促进学校对外交流。通过项目建设，使全体师 生提高信息化思维能力，养成信息化行为方式，遵守信息化交往规则，发展信息化职业能力。 二、数字化校园建设目标 按照“顶层设计、统一标准、数据共享、应用集成、硬件集群（虚拟化）” 的规划建设理念，实现： 1.为教学、科研、管理、生活提供一个开放、协同、高效、便捷的数字化 环境，实现规范高效的管理 2.为领导的决策提供实时有效的信息依据 3.为提升学校的核心竞争力，实现学校的跨越式发展提供有力的支撑 具体目标就是实现“六个数字化”： 环境数字化：构建结构合理、使用方便、高速稳定、安全保密的基础网络。 在此基础上，建立高标准的共享数据中心和统一身份认证及授权中心，统一门户平台以及集成应用软件平台，为实现更科学合理的数字化环境打下坚实的基础。 管理数字化：构建覆盖全校工作流程的、协同的管理信息体系，通过管理信息的同步与共享，畅通学校的信息流，实现管理的科学化、自动化、精细化，突出以人为本的理念，提高管理效率，降低管理成本。 教学数字化：构建综合教学管理的数字化环境，科学统一的配置教学资源， 提高教师、教室、实训室等教学资源的利用率，改革教学模式、手段与方法，丰 富教学资源，提高教学效率与质量。 产学研数字化：构建数字化产学研信息平台，为产学研工作者提供快捷、全面、权威的信息资源，实现教学、科研和实训一体化，提供开放、协同、高效的
(完整版)项目管理思路(提纲)
项目管理思路（提纲） 原则：规范创新项目管理方法，提供标准化的项目管理体系。（这次的思路主要考虑整体、不突出重点。） 一、工程项目管理的基本内容： 1、项目部管理 2、前期管理 3、招标合同管理 4、设计管理 5、总承包管理 6、进度管理 7、质量管理 8、成本管理 9、竣工（收尾）管理 二、项目部管理 1、项目部组织结构：项目部的构成根据项目的发展进度再不断进行调整，先补充预算员、资料员及熟悉酒店项目的机电工程师； 2、项目部职责（分工）：落实责任到岗位，落实责任到人，着重把后面的所有管理内容一项不漏的分配到具体的管理人员上，真正做到“权责明晰，有据可依”； 3、加强项目管理人员的培训及学习工作，紧跟社会行业的前进步伐，提高项目管理人员的业务能力，为新项目的顺利进行提供坚实的基
础； 4、项目部管理制度：以公司现有的规章制度及考核制度为基础，再根据新情况进行一些适当补充与调整。 三、前期管理 1、各种手续、审批报建工作的推进及跟踪，无法办理的事项及时将具体情况及原因反馈给公司领导； 2、联络街道办和公证处对本项目周边毗邻建筑物的现状（特别是裂缝、下沉）进行拍照确认并公证； 3、拆除施工场地内的原有基础或其他障碍物；通水(自来水公司)、通电、办理临时占道、开路口(城管局) 及其他相关手续； 4、根据公司领导的要求及项目实际情况编制项目总开发计划； 四、招标合同管理 1、除审查入围单位的资质等级、营业执照、财务状况外，还应着重对入围单位的办公地点、在建项目（生产厂房）针对人员、质量、安全、环境等进行实地考察，以确定是否满足我方质量、进度等综合要求； 2、根据总开发计划编制专业分包与主要材料、设备的进场计划，明确进场时间；根据专业分包与主要材料、设备的进场计划编制招标、采购计划，并严格执行； 3、对于专业分包，要细化、深化各类发包工程内容的自身招标条件，应事先研究各工程内容建设的时间、验收、保修、交接、资料、协作、费用、安全、场地等接口配合条件，就甲方发包(含总承包)的各内容
自考软件开发工具串讲笔记
《软件开发工具》串讲笔记 第一章绪论 重点背诵： 1、对于CASE工具有两种理解，一种是“计算机辅助软件工程”，另一种是“计算机辅助系统工程”。 2、软件开发工具是引导人们建立正确、有效的概念模式的一种手段。 3、从几十年软件开发工具发展历史中，可以看到软件开发工具一个值得注意的特点是多样性和趋同性的并存。 4、进入二十一世纪以来，软件开发工具的发展有两个鲜明的特点，第一个特点是面向网络，另一个特点是开源软件的兴起和运用。 5、当前我们所要开发的信息系统不同于以前。其重要特征是具有复杂性、多样性和相互关联性。 1.1 软件开发工具的由来 (1)简述软件开发工具的范围？ 在高级程序设计语言（第三代语言）的基础上，为提高软件开发的质量和效率，从规划、分析、设计、测试、成 文和管理各方面，对软件开发者提供各种不同程序帮助的 一类新型软件。 （2）软件开发工具的发展过程 包括以下四个阶段：工具产生之前、通用工具的使用、专用
工具的出现、一体化工具的出现。
论述工具产生之前，第一代到第四代程序设计语言的主要特征？ 1）第一代机器语言阶段：使用“0”和“1”代码进行编程，难于阅读，难于维护，而且程序高度依赖于计算机硬件，难于移植；2）第二代汇编语言：使用助记符来编写程序，由汇编系统将汇编指令转化为机器指令，编程工作量大大降低，但依然依赖于计算机硬件。与此同时，操作系统的出现从另一方面改善了人们应用计算机的条件； 3）第三代高级程序设计语言，高级语言突破了与机器指令一一对应的限制，实现了对机器的独立性，从而大大提高了程序的可移植性。程序员需要逐行编写语句来实现算法的过程，因此它属于过程化的语言； 4）第四代语言（4GL）是非过程化的程序设计语言，用户只说明要求做什么，而把具体的执行步骤交由软件自动执行。 5）利用通用软件作为辅助工具的阶段 利用文字处理软件来编写文档，利用绘图软件来绘制流程图。6）专用软件开发工具阶段 专用软件开发工具是面对某一工作阶段或工作任务的工具，优点是能提高软件开发的质量和效率；缺点是一致性的保持，对软件开发缺乏全面的、统一的支撑环境。
土地开发整理的意义
土地开发整理的意义 近日，**工业区**土地开发整理项目顺利通过验收，欣喜之余，心想一年来的奔波也算是得到了“丰收”。一年的忙碌，换来老百姓的感激，还有什么比这个奖励更有意义呢？ 土地开发整理是指在一定区域内，按照土地利用总体规划、城市规划、土地开发整理专项规划确定的目标和用途，通过采取行政、经济、法律和工程技术等手段，对土地利用状况进行调查、改造、综合整治、提高土地集约利用率和产出率，改善生产、生活条件和生态环境的过程。**工业区山丘面积比重大，自然生态环境恶劣、土地利用条件差、利用率低，已成为影响当地经济发展的制约因素；人口多耕地少，原有土地大多顺坡耕种，土层薄，土壤结构松散，保水保肥能力差，易涝怕旱；土地利用结构也不合理，产量低而不稳，受自然灾害影响比较大，致使农业基础比较薄弱；植被稀少，生态防护效能差，水利设施不配套，灌溉无保证，限制了农业生产的进一步发展。今年进行土地开发整理的**村土地地表高低起伏，土地利用率不高，本着以平整改造荒废地、提高土地利用率、增加耕地面积为主的目的，整理土地1662亩，完成新增耕地895亩。土地整治中，实行田、水、路、林统一规划，既增加了耕地面积、提高了土地利用率，又方便了耕作和田间管理，在多方面都具有积极的意义。
社会效益方面：“三农问题”一直制约着经济的发展，如何为老百姓谋福利是当前政府的重中之重。土地开发整理正是本着为老百姓谋福利这一目的，让老百姓得实惠，促进社会的和谐发展。**项目完成后，土地使用率明显提高，缓解了项目区人多地少的矛盾，增加农业产量，增加农民收入，促进社会经济发展。项目修建田间道路、生产路总长7147米，方便了交通，有利于农业机械作业，改善了耕作条件和生产条件，促进了农业机械化的发展，为农副产品的运销打下了良好的基础，同时加快了农村基础设施建设，改变了脏、乱、差的面貌。项目全部完成后，可极大地改善农村生态环境，提高农民的生活水平。 经济效益方面：实施土地开发整理，提高了项目区原有土地的质量和产值，能有效地增加耕地面积。在农业综合效益方面，土地整理项目不仅通过项目发挥作用为农民带来收益，还在项目建设过程中，吸纳当地农民参与项目建设，解决剩余劳动力的就业问题，直接为农民增收创造了条件。原来灌溉农田时，农民用水泵浇灌，农田水利工程建设完工后，变成了用机电井低压管道灌溉，极大地改善了农民生产条件，节省了灌溉成本，减轻了劳动强度，减少了劳动力投入。**项目区总面积1662亩，总投资195.28万元，新增耕地895亩，用于种植小麦、生姜、地瓜、花生等，年增收入107.45万元。
数字化校园建设项目计划
项目一：数字化校园特色项目建设计划 一、需求论证 信息技术的飞速发展，迅速地改变着人们的学习、工作和生活，也改变着人们的思想、观念和思维方式。这一切都对快速发展中的职业教育和职业学校提出了十分严峻的挑战。现代信息技术正在向职业学校教学、科研、管理的每一个环节渗透，将改变传统的教学模式并大幅度提高教育资源的利用效率。数字化校园、网上学校已被人们熟悉，职业教育正在走向全面的信息化。 数字化校园的建设应用是教育系统信息化的关键，在职业学校建设数字化校园，对于促进教师和学生尽快提高应用信息技术的水平,促进学校教学改革，推行素质教育，促进教学手段的现代化水平,为教师提供一种先进的辅助教学工具、提供丰富的资源库，全面提高学校现代化管理水平，加强学校与外界交流等方面都具有重要作用。 2005年学校完成校园网建设，同时接入因特网，校园网覆盖了所有使用计算机的实验室、各处办公室、各专业组。目前校园网已覆盖整个校园。但数字化教与学以及服务区域职业教育、实现教育资源共享的能力还远远不够。作为一所综合性国家级重点职业学校，以及建设国家中等职业教育改革发展示校的要求，要使其发挥辐射带动作用，达到资源利用最大化，迫切需要我校建设数字化校园，将更大的注意力放在信息化的深入应用上，及早做好规划，将信息化发展推向新水平。 二、建设目标
数字化校园建设的目标主要包括：一是完善校园网基础设施建设，构建技术先进、扩展性强、安全可靠、高速畅通、覆盖本部、一分部、实训基地的校园网络环境；二是建设全校防盗系统；三是完善校园广播系统；四是各种资源应用平台建设；五是建设校园一卡通。 学校通过构建技术先进、扩展性强、安全可靠、高速畅通、覆盖全校的校园网络环境，建立全校公共信息系统，为教与学提供先进数字化管理手段，提高管理效率；建立功能齐全的教学管理系统；配合“工学结合”教学模式，建设容丰富的网络教学资源平台，实现数据资源共享，提高全校师生的信息化水平素养。通过数字化校园的建设项目，为培养高技能应用型人才和服务社会搭建公共服务平台。 三、建设思路 以服务专业建设为出发点，建设数字化校园和教学资源中心。构筑信息交流与资源共享平台，创建开放的教学资源环境，实现优质教学资源网上共享，为实用型技能人才的培养和构建现代化学习环境搭建公共平台，提高管理效率与教学水平。提高全校师生信息化水平素养，以网络为基础，利用先进的信息手段和工具，将学校的各个方面，实现环境（包括网络、设备、教室等）、资源（如图书、讲义、课件等）、活动（包括教、学、管理、服务、办公等）的数字化，逐步形成一个数字校园空间，从而使现实校园在时间和空间上获得延伸，完成数字校园建设，对本地区职业教育信息化建设和发展起到示与带动作用。 四、建设容 （一）校园安全防盗系统
建设银行规划项目管理章程与工作方法
中国建设银行科技应用规划项目项目管理章程和工作方法 中国建设银行 2020年4月2日
目录 1项目人员角色和职责3 2项目运行中的沟通机制 (5) 3项目文档资料管理机制8 4项目人员的考核机制 (12) 5项目培训机制 (14) 6项目验收机制15 项目人员角色和职责 项目领 导委员会 项目总监 /项目管理办公 项目小组 项目领 导委员会 项目总监 质量总监 项目经理 项目小组 1) 项目领导委员会：
由双方的高层领导参加，直接负责项目的成功实施，负责： a)确定项目目标和方向 b)保证资源合理调动，支持项目的推行 c)促使管理层对项目的全力参与和支持 d)验收和审批项目成果 e)授权项目经理开展工作 2)项目总监和质量总监： 项目总监由双方选出的高层领导担任，主要负责： a)对项目过程进行指导和监督 b)确认双方工作职责和安排 c)组织协调项目所需资源的合理调配 d)按项目进度向项目领导委员会汇报 e)定期对项目的工作进度进行监督 f)对项目成果进行确认和验收 毕博管理咨询将另派高层管理人员作为本项目的质量总监，主要负责： a)对本项目的整体质量进行检查和考核 3)项目经理： 项目经理成员由双方的项目经理组成，具体负责： a)策划项目推进和控制项目进程 b)确认项目小组及其成员的工作职责 c)指导及安排项目小组的日常工作 d)定期安排双方沟通、及时调整工作安排 e)现场处理双方可能产生的意见不一致 f)执行项目所需资源的有效调配 g)组织对项目成果的确认和验收 4)项目小组：
项目小组将由小组负责人、咨询顾问、行业专家以及中国建设银行的项目参与人员共同组成。项目小组的职责包括： a)确定项目的工作步骤和具体工作方法 b)具体开展项目工作，包括：收集数据和信息，分析并确定问题，设计解决方案， 讨论和修改工作成果，协助实施 c)根据项目要求，在规定的时间内提交符合质量要求的项目设计方案 项目运行中的沟通机制
软件工程笔记完整版
. 第一章软件工程概述 1.软件危机 (software crisis)：是指在计算机软件的开发和维护过程中所遇到的一系列严重问题。即“两低一高”问题：质量低、效率低、成本高。 软件危机也成为“软件萧条(depression)”或“软件困扰(afflication)” 2.软件危机主要表现 1）开发成本和进度估计不准 2）用户对“已完成的”软件系统不满意 3）软件质量往往靠不住 4）软件常常是不可维护的 5）软件通常没有适当的文档资料 6）软件成本逐年上升 7）软件开发生产率滞后于硬件和计算机应用普及的趋势 3.产生软件危机的原因 1）与软件本身的特点有关 a. 软件不同于硬件，是逻辑部件而不是物理部件 缺乏可见性 难于测试 管理和控制开发过程困难 不会因使用时间过长而被“用坏” 难以维护 b.软件不同于一般程序，规模庞大，而且程序复杂性随着程序规模的增加而呈指数上升 2）和软件开发与维护的方法不正确有关 a.对软件开发和维护有关的错误认识和作法 忽视软件需求分析的重要性 认为软件开发就是写程序 轻视软件维护 b. 对软件开发过程与方法的认识与应用 软件开发要经历一个漫长的时期（编程占10-20%） 程序仅是完成软件配置的一个组成部分 软件开发方法要有利于软件维护 4.软件的特点 (1)软件是无形的（intangible） (2)软件副本的大批量生产轻而易举 (3)软件业是劳动密集型的 (4)一个没有经过充分训练的软件开发人员很容易编写出难以理解和修改的软件 (5)软件本身很容易修改。但由于它的复杂性，又很难正确地修改。 (6)软件不像其他的工业产品那样会因使用而磨损，随着反复修改，它的设计会逐渐退化 5.消除软件危机的途径 1）对计算机软件的正确认识 2）认识到软件开发不是个体劳动的神秘技巧，而是一种组织良好、管理严密、各类人员协
数字化校园管理系统
中小学数字化校园管理系统软件 拟 定 方 案
目录 一、数字校园基础平台： (3) 二、协同办公系统： (5) 三、招生管理系统： (6) 四、学籍管理系统： (7) 五、学费管理系统： (7) 六、学生管理系统： (8) 七、学生请销假管理： (8) 八、量化考核管理系统： (8) 九、教务管理系统： (9) 十、成绩管理系统： (9) 十一、离校管理系统： (10) 十二、资产管理系统： (10) 十三、人事档案管理系统： (11) 十四、数字化图书馆教学资源库、精品课程及网上教学平台： (11)
“数字化校园管理系统” “数字校园管理系统”是针对职业院校信息化建设，研发的数字化校园管理系统。通过电脑或手机等终端，为校长、老师、学生、行政办公人员、学生父母、来访用户及相关应用人员提供高效、便捷的一站式信息服务。实现了校园内各类应用软件高效集成和数据资源高度共享，是最适合中学高中及大学校园信息化建设的管理软件。 下面是平台界面示意图： 一、数字校园基础平台：
数字校园管理系统特点： 产品开发以学校为原型， 技术选型性价比更高。 采用windows server +php + mysql + apache的技术架构。 优势：采用win server 作为操作系统，更容易维护，也符合学校服务器现有情况 采用mysql开源数据库，无需支付软件授权费用，因为mysql是一个开源免费的数据库。但是其性能及稳定性堪称一流，许多大型网站系统都在使用。 PHP是全世界使用量排名第四的编程语言，在B/S结构的系统中有其得天独厚的优势。 我方在提供以开发完毕的整套系统的基础上，后期可根据学校需求进行系统的第二次开发，以适应学校的需求。 数字校园管理系统：多终端访问： 数字校园管理系统基础平台包含内容：
(考研复试)软件工程笔记培训资料
(考研复试)软件工程 笔记
1：软件危机：问题1：如何开发软件，以满足对软件日益增长的需求。问题2：如何维护数量不断膨胀的软件。表现：对软件开发成本和时间估计不准，用户对已完成软件不满意，软件质量不可靠，软件不可维护，软件缺少文档，软件成本过高，软件跟不上硬件发展速度。原因：与软件本身特点有关，缺乏可见性，质量难以评价，规模庞大难以维护。与软件开发维护的不当方法有关，轻视需求分析和维护，对用户的要求没有完整准确的认识就编写程序，忽视程序，文档，数据等软件配置。 2：软件工程：采用工程的概念，原理，技术和方法开发与维护软件，把正确的管理技术和软件开发技术结合起来，经济的开发出高质量的软件并有效的维护。即把系统化的，规范的，可度量的途径应用于软件开发，运行和维护的过程。 3:软件工程7条基本原理：用分阶段的生命周期计划严格管理，坚持进行阶段评审，实行严格的产品控制，采用现代程序设计技术，结果应能清楚地审查，开发小组的人员应该少而精，承认不断改进软件工程实践的必要性。 4：软件工程领域：软件需求，设计，构建（写代码），测试，维护，配置管理，工程管理，工程过程，工程工具，软件质量。
5：软件生命周期：软件定义（问题定义，可行性研究，需求分析），软件开发（概要设计，详细设计，编码和单元测试，综合测试），运行维护（改正性维护，适应性维护，完善性维护，预防性维护）。、 生命周期模型 6：瀑布模型：就是把一个开发过程分成收集需求，分析，设计，编码，测试，维护六部分，只有完成前面一步才能开始后面一步，上一步的输出的文档就是这一步的输入文档，每一步完成都要交出合格的文档，每一步都会有反馈，如果反馈有错误就退回前一步解决问题。瀑布模型的缺点：实际的项目开发很难严格按该模型进行；由于用户只能通过文档来了解产品，客户往往很难清楚地给出所有的需求，而瀑布模型不适应用户需求的变化；软件的实际情况必须到项目开发的后期客户才能看到。 7：快速原型模型：就是根据用户的需求迅速设计出一个原型系统，原型系统具有基本的功能，然后用户使用原型并对原型提出需求和改变，开发人员再对原型进行修改和完善知道用户满意。优点：容易适应需求的变化；有利于开发与培训的同步；开发费用低、开发周期短且对用户更友好。缺点：快速建立起来的系统结构加上连续的修改可能会导致产品质量低下;使用这个模型的前提是要有一个展示
土地开发整理标准(全)
前言 为规范土地开发整理项目规划设计（以下简称“规划设计”）工作、提高规划设计的科学性以及更好地实施土地开发整理规划，根据《中华人民共和国土地管理法》等有关法律、法规、规章制定本标准。 省、自治区、直辖市土地行政主管部门可根据需要制定本标准的补充规定，报国土资源部备案。补充规定不得与本标准相抵触。 本标准从2000年10月1日起实施。 本标准的附录A、附录B、附录C、附录D都是标准的附录。 本标准起草单位：国土资源部土地整理中心。 本标准协作单位：浙江省国土管理局、浙江大学、中国人民大学、北京师范大学。 本标准主要起草人：高向军、范树印、吴次芳、叶艳妹、叶剑平、胡江、吴昌洋、童菊儿、梁进社、张占录、彭群、王爱民。 本标准由国土资源部负责解释。 中华人民共和国国土资源部部标准 土地开发整理项目规划设计规范TD/T1012—2000 1范围 1．1本标准规定了土地开发整理项目规划的总则、内容、程序、方法及成果的基本要求和项目设计的原则、内容及技术要求。 1．2本标准适用于土地开发整理项目规划的编制和土地开发整理项目的设计，并作为与设计有关的概预算、审批等方面的依据。 2引用标准 下列标准所包含的条文，通过在本标准中引用而构成为本标准的条文。本标准出版时，所示版本均为有效。所有标准都会被修订，使用本标准的各方应探讨使用下列标准最新版本的可能性。 GBJ7—1989建筑地基基础设计规范 GB3838—1988地面水环境质量标准 GB5084—1992农田灌溉水质标准 GBT5791一19931：50001：10000地形图图式 GB／T7929一19951：5001：1000，1：2000地形图图式 GB8978—1996污水综合排放标准 GB/T15772—1995水土保持综合治理规划通则 GB/T16453.1—1996水土保持综合治理技术规范坡耕地治理技术 GB/16453.3—1996水土保持综合治理技术规范沟壑治理技术 GB/T16453.4—1996水土保持综合治理技术规范小型蓄排水工程 GB50162—1992道路工程制图标准 GB50188—1993村镇规划标准 GB/T50265—1997泵站设计规范 GB50286—1998堤防工程设计规范 GB50288—1999灌溉与排水工程设计规范 SDJ217—1987水利水电枢纽工程等级划分及设计标准（平原、滨海部分） SL18—1991渠道防渗工程技术规范 SL721994水利建设项目经济评价规范 SL73—1995水利水电工程制图标准 JT／J021—1989公路涵桥设计通用规范 L Y/J002—1987林业工程制图标准 3土地开发整理项目规划设计规范规划
工作笔记_NetBeans 开发工具及开发问题
NetBeans 开发工具 NetBeans 乱码 不太明白，看看我理解的对不对。你是不是在导入别的代码时，其中的汉字显示不正常，而自己敲进去汉字显示是正常的。 NetBeans默认的编码方式：UTF-8，而其他IDE不同，所以会有显示错误 试试在“项目/文件/服务”的项目窗口中，你的项目名上右击，选择“项目属性”，“常规”类别中的“编码”栏中选择GBK，ISO-8859-1等看看能不能显示正常。。。 补： 建议你到https://www.wendangku.net/doc/081363651.html,/downloads/index.html 直接下NetBeans6.9 （语言：简体中文NetBeans IDE 下载包all）的吧。执行中出现https://www.wendangku.net/doc/081363651.html,ng.RuntimeException： https://www.wendangku.net/doc/081363651.html,ng.RuntimeException: Uncompilable source code - Erroneous sym type: (https://www.wendangku.net/doc/081363651.html,ng.String,https://www.wendangku.net/doc/081363651.html,ng.String,
2019年土地开发整理标准(全)
前
言
为规范土地开发整理项目规划设计（以下简称“规划设计”）工作 、提高规划设计得科学性以及更 好地实施土地开发整理规划，根据《中华人民共与国土地管理法》等有关法律、法规、规章制定本标准。
省、自治区、直辖市土地行政主管部门可根据需要制定本标准得补充规定，报国土资源部备案。补 充规定不得与本标准相抵触。
本标准从 2000 年 10 月 1 日起实施。 本标准得附录 A、附录 B、附录 C、附录 D 都就是标准得附录。 本标准起草单位：国土资源部土地整理中心。 本标准协作单位：浙江省国土管理局、浙江大学、中国人民大学、北京师范大学。 本标准主要起草人：高向军、范树印、吴次芳、叶艳妹、叶剑平、胡江、吴昌洋、童菊儿、梁进社、 张占录、彭群、王爱民。 本标准由国土资源部负责解释。 中华人民共与国国土资源部部标准 土地开发整理项目规划设计规范 TD/T1012—2000
1 范围
1．1 本标准规定了土地开发整理项目规划得总则、内容、程序、方法及成果得基本要求与项目设计得原则、 内容及技术要求。 1．2 本标准适用于土地开发整理项目规划得编制与土地开发整理项目得设计，并作为与设计有关得概预算、 审批等方面得依据。
2 引用标准
下列标准所包含得条文，通过在本标准中引用而构成为本标准得条文。本标准出版时，所示版本均为 有效。所有标准都会被修订，使用本标准得各方应探讨使用下列标准最新版本得可能性。
GBJ 7—1989 建筑地基基础设计规范 GB 3838—1988 地面水环境质量标准 GB 5084—1992 农田灌溉水质标准 GB T5791 一 1993 1：5000 1：10000 地形图图式 GB／T7929 一 1995 1：500 1：1000，1：2000 地形图图式 GB 8978—1996 污水综合排放标准 GB/T 15772—1995 水土保持综合治理 规划通则 GB/T16453、1—1996 水土保持综合治理 技术规范 坡耕地治理技术 GB/16453、3—1996 水土保持综合治理 技术规范 沟壑治理技术 GB/T 16453、4—1996 水土保持综合治理 技术规范 小型蓄排水工程 GB 50162—1992 道路工程制图标准 GB 50188—1993 村镇规划标准 GB/T 50265—1997 泵站设计规范 GB 50286—1998 堤防工程设计规范 GB 50288—1999 灌溉与排水工程设计规范 SDJ 217—1987 水利水电枢纽工程等级划分及设计标准（平原、滨海部分） SL 18—1991 渠道防渗工程技术规范 SL 721994 水利建设项目经济评价规范 SL 73—1995 水利水电工程制图标准 JT／J 021—1989 公路涵桥设计通用规范 LY/J002—1987 林业工程制图标准
3 土地开发整理项目规划设计规范规划
3、1 总则 3、1、1 本标准所称土地开发整理包括土地开发、土地整理、土地复垦。 3、1、2 规划得基本原则
a） 十分珍惜、合理利用土地与切实保护耕地。 b） 社会效益、经济效益、生态效益相统一。
项目管理方法
项目管理方法 项目管理方法是关于如何进行项目管理的方法，是可在大部分项目中应用的方法。主要有：阶段化管理、量化管理和优化管理三个方面. 管理概述 项目管理是一个管理学分支的学科，指在项目活动中运用专门的知识、技能、工具和方法，使项目能够在有限资源限定条件下，实现或超过设定的需求和期望。项目管理是对一些与成功地达成一系列目标相关的活动(譬如任务)的整体。这包括策划、进度计划和维护组成项目的活动的进展。项目管理方法是关于如何进行项目管理的方法，是可在大部分项目中应用的方法。在项目管理方法论上主要有：阶段化管理、量化管理和优化管理三个方面。[1] 阶段管理 阶段化管理指的是从立项之初直到系统运行维护的全过程。根据工程项目的特点，我们可将项目管理分为若干个小的阶段。 市场信息 1）市场信息方面可分为：信息采集、信息分析、工程项目立项及项目申请书的编写。 ①信息采集：可分为工程项目信息与常规设备与器材的市场信息的采集。这些信息通过业务员或其它通道获得，一旦获得后，信息提供者应以书面形式向公司有关部门予以报告。 ②信息分析：公司在这方面应该设立专门的部门对各种信息进行分类、编辑、管理、核实、分析与论证，在考虑项目时不但要看社会是否需要，而且还要研究个人、组织或社会是否有能力投入足够的资源将其实现，实现之后能否为资源投入者和社会真正带来利益。通过对项目的可行性研究为信息的确定提供切实可行的依据。并监督业务工作人员的
工作效率以及其绩效评价。 ③工程项目立项：根据信息分析部门所提供的分析与认证报告，确定信息的处理方式，并上报公司决策层予以决策。公司决策层通过信息分析部门的信息分析报告结合公司的经营状况，对信息进行确定是否立项，一旦立项，就要分析会有哪些承约商参加投标，各自的优势以及他们同客户的关系。主要考虑的因素包括自身的技术能力、项目风险、资源配置能力及其它因素。同时也可对信息分析部门的工作效率以及其绩效评价。 申请书填写 项目申请书：当决定参加投标竞争的时候上，就需要完成一份项目的申请书或称为投标书，一份完整的申请书一般包括三个部分的内容，即技术、管理、成本三个方面。如果是一份较复杂的申请书，这三部分可能是三个独立的册子： 技术部分的目的是让客户认识到：承约商对其需求和问题的理解，并且能够提供风险最低且收益最大的解决方案。 管理部分的目的是使客户确信，承约商能够做好项目所提出的工作，并且收到预期的结果。 成本部分的目的是使客户确信，承约商申请项目所提出的价格是现实的、合理的。 这一部分任务将由公司的技术支持部门根据市场信息部门的有关报告完成，同样也可以通过其工作效率及质量对其进行绩效评价。 申请书完成后 在项目申请书完成的同时，市场信息部门的所有部门都应密切注视该项目的进展情况，及时更新项目的最新状况，并通报各有关部门特别是技术支持部门，使该部门能根据项目的最新情况调整项目申请书。以增大我们在项目中的竞争能力。 在合同的签订即项目确定之后，项目管理又可划分为项目准备阶段、项目实施阶段、竣工验收阶段及系统运行维护阶段等。各阶段的工作内容的不同，其实施与管理也应各异。 ①项目准备阶段：其项目实施管理方式的确定(即项目组织)，各种资源的配备与落实，以及具体项目实施方案的进一步确定。即根据项目的特点，对项目作业进行分解，确定其阶段性成果验收，以及必要的监督反馈，这样就能够很好地解决项目组织与客户的分歧，增加项目风险的可控性。 ②项目实施阶段：根据项目实施的具体方案，并以各阶段性成果按其技术要求、质量保证进行验收。这样，在每个阶段完成后，客户和项目