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1.
为调查玉米/大豆间作种植模式对农田大型土壤动物群落结构动态特征的影响,采用手拣法捕获土壤动物,于2016年6~9月玉米生育期内对大型土壤动物群落组成、多样性、垂直分布和功能群特征进行了研究。结果表明:玉米生育期共捕获大型土壤动物818只,隶属于34个类群。大型土壤动物个体数随玉米生长呈现逐渐增加的趋势,在拔节期间作种植显著提高了土壤动物个体数(P<0.05);玉米拔节、抽穗和成熟期10~20 cm土层大型土壤动物个体数显著高于0~10和20~30 cm土层(P<0.05)。Shannon-Weiner指数和Margalef指数随玉米生长呈现先升高后下降的趋势,在拔节期Shannon-Weiner指数和Margalef指数均最大;Simpson指数总体与Shannon-Weiner指数变化趋势相反,随玉米生长呈现先下降后升高的趋势。间作种植在成熟期显著提高了植食性大型土壤动物个体数,在拔节期显著提高了捕食性和腐食性大型土壤动物个体数(P<0.05);植食性和腐食性大型土壤动物个体数随玉米生长呈增加的趋势;捕食性大型土壤动物个体数随玉米生育期基本呈增加的趋势。  相似文献   

2.
摘 要 调查不同玉米秸秆还田量下农田大型土壤动物群落动态特征,于2016年6—9月玉米生育期内进行,采用手拣法捕获土壤动物。结果表明:共捕获大型土壤动物2 681只,隶属于41个类群。方差分析显示,13 500 kg?hm-2还田处理(SR4)显著提高了大型土壤动物个体数,12 000 kg?hm-2还田处理(SR3)显著提高了大型土壤动物类群数。多样性表明:多样性指数和丰富度指数随玉米生长季总体呈现出先增加后下降的趋势;均匀度指数随玉米生长季总体呈现出下降的趋势;优势度指数总体与多样性指数变化趋势相反,随玉米生长季呈现出先下降后增加的趋势。垂直分布表明:随玉米的生长时期的推移,表层0~10 cm土层的大型土壤动物有向10~20 cm土层下移的趋势。功能群特征表明:捕食性大型土壤动物个体数随玉米生长季呈现先增加后下降的趋势;植食性和腐食性大型土壤动物个体数随玉米生长季呈现增加的趋势;杂食性大型土壤动物个体数在玉米生长季无明显变化。RDA分析表明:受农田土壤环境因子影响较大的大型土壤动物类群主要是研究区的优势类群,大型土壤动物的个体数与土壤有机质含量和土壤含水量关系紧密。总体上,玉米秸秆还田影响地表土壤的微环境,进而影响了大型土壤动物群落的组成、分布特征和功能群,玉米秸秆还田有益于农田大型土壤动物功能群的发展。  相似文献   

3.
中小型土壤动物对环境变化反应敏感,不同种植方式导致农田土壤空间格局改变将影响中小型土壤动物群落多样性和功能。本文通过玉米单作和间作种植,在玉米生长季的不同月份调查取样,研究玉米单作和间作种植对土壤动物的个体数量、类群数、多样性和不同功能群的影响。结果表明:从试验样地共捕获中小型土壤动物1 473只,隶属于40个类群;玉米间作种植显著降低中小型土壤动物的个体数(P 0. 05),玉米间作种植降低中小型土壤动物类群数,未达到显著水平(P 0. 05),这种降低趋势在不同月份和土层中均表现出来;玉米单作和间作种植下中小型土壤动物总体趋势为腐食性杂食性捕食性+植食性的个体数(P 0. 05);玉米间作种植增加了优势度指数,降低了多样性指数、均匀度指数和丰富度指数(P 0. 05);玉米间作种植改变了不同食性中小型土壤动物的个体数和类群数,腐食性、杂食性和捕食性+植食性土壤动物数量降低,杂食性和捕食性+植食性的土壤动物类群数增加,腐食性土壤动物类群数降低,但个体数和类群数的变化未达到显著水平(P 0. 05)。  相似文献   

4.
吉林黑土区不同施肥条件下农田土壤动物组成及多样性变化   总被引:14,自引:0,他引:14  
采用手捡法和改良干漏斗法(Modified.Tullgren)对吉林黑土区长期定位施肥农田土壤动物群落组成及多样性进行研究。12个施肥小区内共采集108个土壤样品,获得农田土壤动物标本17265只(未鉴定标本187只),隶属3门9纲19目3亚目48科。统计分析结果表明,所采集标本中,营养功能群以植食性(35.53%)为主。其中,大型农田土壤动物捕获的个体数和类群数以撂荒和施氮肥区最多;中小型农田土壤动物则以撂荒和轮作区最多;大型农田土壤动物群落的多样性指数(H′)依次是NP>N>1.5MNPK>PK>M2NPK>CK>NK>NPK>M1NPK>轮作>SNPK>撂荒,中小型农田土壤动物多样性指数依次是M1NPK>M2NPK>SNPK>1.5MNPK>NP>CK>轮作>NK>NPK>PK>N>撂荒。群落相似性指数分析表明,不同施肥之间相似性系数一般较低。农田土壤动物群落组成异质性较高,SNPK与M1NPK、撂荒地处理之间的相似性明显高于其他群落,N与SNPK、M2NPK和轮作之间、CK与1.5MNPK和NPK之间的相似性明显低于其它施肥之间的相似性。反映出不同施肥处理对土壤生态系统内部环境,进而对土壤动物群落产生的影响。  相似文献   

5.
不同耕作方式下黑土区农田中小型土壤动物群落特征   总被引:3,自引:0,他引:3  
[目的]研究中小型土壤动物群落组成、多样性、动态特征及垂直分布情况,反映土壤环境状况,为探索黑土区农田适宜的耕作方式提供参考依据。[方法]采用改良干漏斗(modified tullgren)法分离中小型土壤动物,分析比较了不同耕作方式下中小型土壤动物的群落结构及分布特征。[结果]从研究样地共捕获中小型土壤动物3 749只,隶属47个类群。其中四奥甲螨科(Quadroppiidae)和等节■科(Isotomidae)为试验区的优势类群。3种耕作方式下,0—10 cm土层中小型土壤动物个体数占总个体数的71%,在垂直分布上具有明显的表聚性。深松处理下中小型土壤动物个体数最多(1 671),CK处理下类群数最多(41)。CK处理下中小型土壤动物多样性指数和丰富度指数最高,分别为(2.81)和(3.81);深松处理下中小型土壤动物优势度指数最高(0.15)。不同耕作方式下土壤渗透总量表现为深松CK免耕;土壤含水量和土壤温度表现为深松免耕CK;土壤容重表现为免耕CK深松。中小型土壤动物个体数与土壤容重呈显著正相关(p0.05);中小型土壤动物丰富度指数与土壤有机质呈显著正相关(p0.05);中小型土壤动物均匀度指数与土壤渗透总量呈极显著正相关(p0.01)。[结论]耕作方式对中小型土壤动物的群落结构有明显的影响,深松耕作后显著提高中小型土壤动物个体数,能够有效改善土壤环境,比免耕和传统耕作更有利于中小型土壤动物的生存与繁殖。  相似文献   

6.
【目的】明确新疆西天山不同海拔高度雪岭云杉林下大型土壤动物群落的组成、分布特征和多样性,为当地森林资源生态系统健康评价、土地利用管理及资源可持续利用提供土壤动物学依据。【方法】选取新疆西天山不同海拔高度雪岭云杉林样地(Ⅰ,海拔1414 m;Ⅱ,海拔1595 m;Ⅲ,海拔1724 m;Ⅳ,海拔1868 m),使用手捡法收集云杉林下大型土壤动物,采用单因素方差分析(One-way ANOVA)和最小显著差异法(LSD)比较大型土壤动物群落不同数据组间的差异,采用冗余分析(Redundancy analysis, RDA)排序方法分析土壤动物群落物种重要值与环境变量的关系。【结果】四个样地共捕获大型土壤动物427只,隶属于3门7纲16目23科。四个样地垂直分布特征表现为样地Ⅱ大型土壤动物平均密度在7月的表聚性特征较为明显,随着土层深入呈现递减趋势,其它样地无明显的分布规律。大型土壤动物多样性指数、均匀度指数、优势度指数和丰富度指数在不同海拔高度均有所不同,样地Ⅰ大型土壤动物的多样性指数、均匀度指数和丰富度指数为四个海拔中最高。各个样地杂食性大型土壤动物的个体密度所占4个功能群个体密度总量的比...  相似文献   

7.
为了解不同利用方式土地大型土壤动物群落结构,于2006年冬季和2007年春季对四川紫色土丘陵区农田边界、农田、果园和退耕林地进行了大型土壤动物调查,采用野外手捡法共采集大型土壤动物2 838只,隶属于3门9纲24类.研究结果表明:不同土地利用方式大型土壤动物群落的个体密度、类群数和DG多样性指数存在差异.冬季,农田边界的个体密度显著高于其他土地利用方式,类群数和DG多样性指数显著高于退耕林地和农田;农田的个体密度、类群数和DG多样性指数明显处于最低水平.大型土壤动物群落的个体密度和类群数在垂直分布上具有明显的表聚性.Jaccard相似性系数和Grower系数表明农田边界、果园与退耕林地三者间相似程度较高,农田与农田边界、退耕林地、果园之间相似程度较低.研究认为土地利用方式对大型土壤动物的群落结构有明显影响,农田边界的存在对大型土壤动物生物多样性的保护具有重要意义.  相似文献   

8.
石油烃类污染物降解动力学和微生物群落多样性分析   总被引:3,自引:0,他引:3  
为了探讨不同初始浓度石油污染土壤堆腐化修复机制,以石油降解菌剂和腐熟鸡粪为调理剂,研究了初始浓度分别为5 000(T1)、10 000(T2)和50 000 mg/kg(T3)的石油污染土壤堆腐化修复过程石油烃类污染物降解动力学特征和微生物群落多样性。结果表明:堆腐化修复过程石油烃类污染物降解符合一级反应动力学,反应常数分别为0.012、0.094和0.050 d-1,半衰期分别为6.79、7.37和13.86 d。整个堆腐过程石油烃类污染物平均降解速率分别为112.08、230.05和887.93 mg/(kg·d)。3个处理的孔平均颜色变化率(average well color development)和碳源利用率(除芳香烃类化合物外)随堆腐进程的推进逐渐升高,在堆腐中、后期达到最大,T3处理显著高于T1、T2处理。多聚物类和糖类代谢群是堆腐体系中的优势菌群。主成分分析表明3个处理的微生物群落差异显著(除第9天外),起分异作用的碳源主要是糖类和羧酸类。微生物群落的丰富度指数和均一度指数随堆腐进程的推进逐渐升高并在堆腐后期达到最大,与T1处理相比,T3处理分别高了0.21%和17.64%,差异达到显著水平(P0.05)。微生物群落优势度指数在中期达到最大,T1处理分别比T2、T3处理高2.12%和9.44%,3个处理间差异不显著(P0.05)。堆肥结束时3个处理的种子发芽指数(seed germination index,SGI)分别比堆腐初期提高了18.26%、20.42%和36.41%。该研究结果为黄土高原不同程度石油污染土壤堆腐化修复的应用提供参考依据和理论基础。  相似文献   

9.
稻蟹共作对稻田水体底栖动物多样性的影响   总被引:2,自引:0,他引:2  
稻蟹共作是一种生态型种养新模式,而底栖动物是该复合生态系统的重要组成部分。为研究稻蟹共作对稻田底栖动物多样性的影响,在水稻分蘖期、拔节期、扬花期和成熟期,采集不同放养密度的稻蟹共作稻田(仔蟹放养密度10 ind.m 2,低密度,LD;仔蟹放养密度30 ind.m 2,高密度,HD)和常规稻田(不放蟹,常规栽培,CK)水体的底栖动物,分析不同稻田生态系统底栖动物的种类构成、密度和多样性。结果表明:水稻分蘖期,3种放蟹密度处理稻田底栖动物的种类数、密度、多样性指数和Pielou均匀度指数均无显著差异(P>0.05);在拔节期和扬花期,养蟹稻田底栖动物的种类数和密度均小于常规稻田,且与放蟹密度呈反比;常规稻田底栖动物的Shannon-Wiener多样性指数在拔节期和扬花期均显著高于高密度养蟹稻田(P<0.05),而只在拔节期显著高于低密度养蟹稻田(P<0.05),且Pielou均匀度指数也在拔节期显著高于低密度养蟹稻田(P<0.05);成熟期,3种处理底栖动物的种类数和密度均达到最低点,Shannon-Wiener多样性指数无显著差异(P>0.05),高密度养蟹稻田的Pielou均匀度指数显著高于常规稻田(P<0.05)。研究结果可为稻蟹共作稻田底栖动物的多样性保护和稻蟹共作技术的可持续发展提供理论指导,促进稻蟹共作技术的发展和推广。  相似文献   

10.
采用石灰和有效微生物群(Effective Microoganisms,EM)处理改善了大兴安岭森林生态系统土壤微酸性环境和较低的微生物活性特征,于2003~2005年采用网袋分解法,揭示土壤动物群落多样性特征,为土壤动物生态地理研究和森林生态系统管理提供科学依据。研究表明,分解袋内土壤动物多样性对石灰和EM处理的响应表现出以下特征:(1)处理样地土壤动物个体数增加但类群数减少,其中螨类和弹尾类增加明显。(2)石灰和EM处理降低了土壤动物群落的多样性,对应分析表明石灰样地与其他样地有所差异。(3)各样地不同网孔分解袋中土壤动物类群数表现为大孔>中孔>小孔,而个体数基本上为中孔>大孔>小孔,是由于网袋内中小型土壤动物占优势而大型土壤动物数量较少引起的。(4)土壤动物类群数、个体数和多样性指数在针叶和阔叶网袋中响应特征不同,但彼此间没有显著差异。  相似文献   

11.
A field experiment was carried out in northern Vietnam to investigate the effects of adding different additives [rice (Oriza sativa L.) straw only, or rice straw with added lime, superphosphate (SSP), urea or a mixture of selected microorganism species] on nitrogen (N) losses and nutrient concentrations in manure composts. The composts and fresh manure were applied to a three-crop per year sequence (maize–rice–rice) on a degraded soil (Plinthic Acrisol/Plinthaquult) to investigate the effects of manure type on crop yield, N uptake and fertilizer value. Total N losses during composting with SSP were 20% of initial total N, while with other additives they were 30–35%. With SSP as a compost additive, 65–85% of the initial ammonium-N (NH4-N) in the manure remained in the compost compared with 25% for microorganisms and 30% for lime. Nitrogen uptake efficiency (NUE) of fresh manure was lower than that of composted manure when applied to maize (Zea mays L.), but higher when applied to rice (Oriza sativa L.). The NUE of compost with SSP was generally higher than that of compost with straw only and lime. The mineral fertilizer equivalent (MFE) of manure types for maize decreased in the order: manure composted with SSP?>?manure composted with straw only and fresh manure?>?manure composted with lime. For rice, the corresponding order was: fresh manure?>?manure composted with SSP/microorganisms/urea?>?manure composted with lime/with straw alone. The MFE was higher when 5 tons manure ha?1 were applied than when 10 tons manure ha?1 were applied throughout the crop sequence. The residual effect of composted manures (determined in a fourth crop, with no manure applied) was generally 50% higher than that of fresh manure after one year of manure and compost application. Thus, addition of SSP during composting improved the field fertilizer value of composted pig manure the most.  相似文献   

12.
Manufactured soil for landscaping purposes was produced by composting for 6 weeks (1) municipal green waste alone, (2) green waste amended with 25% v/v poultry manure, or (3) green waste immersed in, and then removed from, a mixture of liquid grease trap waste/septage. Composting temperatures increased most rapidly and reached highest values (78oC) in the grease trap/septage-amended green waste. In comparison with green waste alone, addition of poultry manure prolonged the period of elevated temperatures and increased the maximum temperature attained from 52oC to 61oC. Following composting, each of the materials was split into (1) 100% compost, (2) 80% compost plus 20% v/v soil, and (3) 70% compost plus 20% soil plus 10% coal fly ash. Addition of poultry manure or grease trap/septage to green waste prior to composting increased bulk density and reduced total porosity of the composted product. Addition of soil, or soil and ash, to composts increased bulk density, reduced total porosity, decreased percentage macropores, and increased percentage mesopores and available water-holding capacity. Bicarbonate-extractable P, exchangeable NH4+ and NO3, electrical conductivity (EC), soluble C, soluble C as a percentage of organic C, basal respiration, and metabolic quotient were all markedly greater in the grease trap/septage-amended than poultry manure-amended or green waste alone treatments. Values for extractable P and EC were considered large enough to be damaging to plant growth and germination index (GI) of watercress was less than 60% for all grease trap/septage composts. Extractable P and EC were also high, and GI was <100%, in the green waste alone and poultry manure-amended green waste alone treatments. Addition of soil or soil and ash to these composts resulted in GI values >100%.  相似文献   

13.
猪粪比例对烟草废弃物高温堆肥腐熟进程的影响   总被引:1,自引:0,他引:1  
以烟草废弃物为基本原料进行堆肥试验,研究了不同比例猪粪与烟草废弃物混合堆肥体系中温度、pH、全氮、C/N比、水溶性NH+4-N和种子发芽指数(GI,germination index)的动态变化规律,探讨了不同猪粪比例对烟草废弃物高温堆肥腐熟进程的影响。结果表明,在烟草废弃物中加入猪粪能缩短进入高温分解阶段的时间,增加高温分解持续时间,增加全氮含量,加快物料NH+4-N和C/N比降低的速率,加快烟草废弃物堆肥腐熟化进程。添加一定比例猪粪的处理(烟草废弃物∶猪粪=7∶3、烟草废弃物∶猪粪=8∶2和烟草废弃物∶猪粪=9∶1),分别在堆肥第3、4、5 d进入高温分解阶段(〉50 ℃),高温持续时间分别为11、10、8 d;而纯烟草废弃物处理,最高温度为43 ℃,未进入高温分解阶段;至堆肥26 d,NH+4-N含量分别比纯烟草废弃物对照降低47.7%、61.9%和25.6%;GI分别达到81.4%、84.1%和83.7%。  相似文献   

14.
Manures lose N through volatilization almost immediately after deposit. Attempts to control losses include the addition of a C source to stimulate nitrogen immobilization. Composting is a treatment process that recommends the addition of carbonaceous materials to achieve a C:N ratio of 30:1 to stimulate degradation and immobilize nitrogen. Dairies near cities may be able to reduce N loss from manures by composting with urban carbonaceous residues such as municipal solid waste (MSW) or MSW compost that, by themselves, have little agronomic value. Studies were conducted using a self-heating laboratory composter where dairy solids were mixed with MSW compost to determine the reduction of N loss during composting. One-to-one mixtures (v/v) of dairy manure solids and MSW compost were composted and NH3 volatilization, CO2 evolution and temperatures were compared to composting of manure alone. Addition of MSW compost resulted in increased CO2 evolution and reduced N loss. Nitrogen loss from composting dairy manure alone was four to ten times greater than that from composting dairy manure mixed with MSW compost. Adjustment of the C:N ratio to 25 by adding MSW compost to manure appeared to be the major factor in reducing N losses.  相似文献   

15.
Assessment of compost maturity is important for successful use of composts in agricultural and horticultural production. We assessed the “maturity” of four different sawdust-based composts. We composted sawdust with either cannery waste (CW), duck manure (DM), dairy (heifer) manure (HM) or potato culls (PC) for approximately one year. Windrows were turned weekly for the first 60 days of composting, covered for four winter months and then turned monthly for six more months. We measured compost microbial respiration (CO2 loss), total C and N, C:N ratio, water soluble NO3-N and NH4-N, dissolved organic carbon (DOC), pH and electrical conductivity at selected dates over 370 days. Compost effects on ryegrass biomass and N uptake were evaluated in a greenhouse study. We related compost variables to ryegrass growth and N uptake using regression analysis. All composts maintained high respiration rates during the first 60 days of composting. Ammonium-N concentrations declined within the first 60 days of composting, while NO3-N concentrations did not increase until 200+ days. After 250+ days, DM and PC composts produced significantly more ryegrass biomass than either CW or HM composts. Total C, microbial respiration and water-extractable NO3-N were good predictors of compost stability/maturity, or compost resistance to change, while dissolved organic carbon, C:N ratio and EC were not. The compost NO3-N/CO2-C ratio was calculated as a parameter reflecting the increase in net N mineralization and the decrease in respiration rate. At ratio values >8 mg NO3-N/mg CO2-C/day, ryegrass growth and N uptake were at their maximum for three of the four composts, suggesting the ratio has potential as a useful index of compost maturity.  相似文献   

16.
We conducted a field experiment to evaluate alternatives to poultry manure, the normal fertilizer used for growing dust control crops and native vegetation on bauxite residue sand. We compared plant growth, nutrient uptake and residue properties after applications of poultry manure, compost, composted poultry manure and inorganic fertilizer. The compost used was prepared from green waste treated with piggery waste. Plant growth was poor under the compost and composted poultry manure treatments, which produced 0.69 and 1.11 t ha? 1 of above ground biomass, respectively. This compared with 2.43 t ha? 1 from the inorganic fertilizer treatment which had a similar biomass to the poultry manure treatment (3.00 t ha? 1). All treatments, including poultry manure, had low foliar concentrations of some nutrients, with low levels of N, P, K, Mg, Cu and Zn found in most treatments. Of the two treatments which gave effective dust control (inorganic fertilizer and poultry manure) the most economical was inorganic fertilizer which cost A$1227 ha? 1. The high application rate of the poultry manure made it the most expensive fertilizer treatment at a cost of A$1650 ha? 1. There appeared to be no long-term benefit of using organic amendments, as organic fertilizers did not improve residue conditions (organic matter content, pH, electrical conductivity, activity of Na+ ions) compared with the inorganic fertilizer. It was concluded that inorganic fertilizer could provide a suitable, cost-effective alternative to poultry manure for growth of dust control crops, with further research required to address low levels of some nutrients.  相似文献   

17.
Municipal solid waste (MSW) compost from aerobic or anaerobic bioprocesses was evaluated as components of substrates for potted plant production. Experiments were conducted with potted media consisting of MSW compost mixed with other conventional substrates (peat or composted pine bark). Spring barley (Hordeum vulgare L.) and cress (Lepidium sativum L.) were used to evaluate the biological quality of composts. Higher germination rates of spring barley were obtained when MSW compost from aerobic treatment was employed as compared with MSW compost from the anaerobic bioprocess. Improved biological indices were observed when MSW composts were mixed with composted pine bark rather than with peat. Mixtures of 75% aerobic MSW compost and 25% composted pine bark were more favorable for cress growth than peat as sole substrate.  相似文献   

18.
Effectively utilizing composts requires that their nitrogen (N) and phosphorus (P) contents be used as fertilizer, but how this is best accomplished is not fully understood. The authors' objective was to quantify N and P availability of a calcareous clay loam soil receiving composts derived from four contrasting beef cattle feedlot feedstocks applied at 50, 150, and 450 mg total P kg?1 and supplemented twice with fertilizer N for a 42-week greenhouse plant bioassay. Three composted manures from beef cattle fed distinct diets and a composted mix of slaughterhouse and construction waste were applied. Inorganically fertilized and non-amended soils were included as controls. Canola (Brassica napus L.) and pea (Pisum sativum L.) were grown in pots containing 1.5 kg air-dried soil for six alternating 7-week cycles. Soils amended with composted manure from beef cattle fed typical finishing diets had the lowest apparent N recovery (31%) and the greatest soil nitrate after 42 weeks (25 mg N kg?1). Phosphorus availability was greater with composted manure from beef cattle fed distillers' dried grains than composted manure from beef cattle fed typical finishing diets and a composted mixture of slaughterhouse and construction waste. Apparent P recovery (66%) was greatest from composted manure of beef cattle fed corn (Zea mays L.) distillers' dried grains applied at 50 mg total P kg?1. Composted manure from beef cattle fed distillers' dried grains had greater P availability than conventional composted beef cattle feedlot manure. Overall, performance of the composted mixture of slaughterhouse and construction waste was similar to the composted beef cattle manures.  相似文献   

19.
Effects of composting manure on viability of Giardia cysts (GC) and Cryptosporidium cysts (CO) were determined in a two-year study with manure from feedlot cattle bedded on barley straw or woodchips. Each year, manure was deposited in 8 m × 2.5 m × 2 m windrows (one per bedding type) on a sheltered concrete pad. On day 0, porous bags containing 100 g of feces from confirmed Giardia- and Cryptosporidium-positive cattle (9 bags per retrieval day in Year 1; 3 per day in Year 2) were implanted in the windrows. Replicate bags were placed on the concrete pads as uncomposted controls. Windrow temperature and water content were measured and compost was turned mechanically twice each week. Fecal bags were retrieved and subsampled for enumerations of total and viable cysts and cysts after 1, 2, 3, 7, 10, 17, 24 and 31 days in 1998 and after 1, 2, 3, 7, 9, 16, 23, 30, 42, 56, 70 and 98 days in 1999. Windrow temperatures (TEMP) exceeded 55°C during the fourth week of composting, and remained above 50°C for 4 wk thereafter in 1999. Bedding material did not affect overall mean temperature in either year, but TEMP was higher with straw than with woodchip from day 10 to day 17 in 1998 (P < 0.05) and on day 16 and day 42 in 1999 (P < 0.10). In 1998, moisture content decreased from 62.2 to 43.2% during composting of woodchip manure and from 67.3 to 39.3% during composting of straw manure. In 1999, moisture content decreased from 61.0 to 31.8% for woodchip and from 64.5 to 28.6% for straw compost. Percentage of viable CO declined gradually over the 31 days in 1998. The following year revealed a rapid decline in viability of GC and CO once compost temperature exceeded 55°C and viabilities of GC and CO were reduced to zero after 42 days (straw compost) and after 56 days (woodchip compost). Exposure of CO and GC to temperatures > 55°C for a period of 15 days appears to be an effective method of inactivating Giardia cysts and Cryptosporidium cysts in feedlot manure.  相似文献   

20.
Abstract

Soil pH can be increased by manure or compost application because feed rations usually contain calcium carbonate. This study was conducted from 1992 to 1996 to evaluate effects of phosphorus (P) and nitrogen (N)‐based manure and compost application management strategies on soil pH level. Composted and uncomposted beef cattle (Bos taunts) feedlot manure was applied to supply N or P needs of corn (Zea mays L.) for either a one‐ or two‐year period. Phosphorus‐based manure or compost treatments also received additional fertilizer N (ammonium nitrate) to provide for a total of 151‐kg available N ha‐1 yr‐1. Fertilized and unfertilized checks also were included. Manure and composted manure contained about 9 g CaCO3kg‐1 resulting in application rates of up to 1730 kg CaCO3 ha‐1 in 4 years. The surface soil (0–150 mm) pH was significantly decreased with ammonium nitrate application compared to soil in the unfertilized check or to soil receiving manure or compost. Soil pH was significantly increased with the N‐based management strategy compared with the soil original level. In contrast, 4 yr of P‐based manure and compost application strategy maintained soil pH at the original level. Nitrogen‐based applications resulted in higher soil pH than P‐based. Beef cattle feedlot manure and compost can be good sources of CaCO3 for soils requiring lime addition.  相似文献   

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