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1.
山东省泰安市28个桑园的土壤肥力数值化综合评价   总被引：1，自引：0，他引：1  
为了准确评估不同桑园的土壤肥力状况,采用比色法、原子吸收法等化学分析方法测定山东省泰安市岱岳区28个桑园的土壤养分含量,利用模糊数学方法中的综合指数评价模型,结合因子分析、主成分分析、聚类分析等方法,对28个桑园土壤的15项土壤肥力属性进行分析之后,对各桑园的土壤肥力状况进行综合评价和分级。调查的28个桑园的土壤pH适宜,大部分桑园土壤有机质和氮、镁、锌元素含量偏低,个别桑园缺乏其它营养元素。桑园土壤肥力综合评价的最小数据库集(MDS)包含全氮、pH值、碱解氮、有效铁、速效磷、速效钾、有机质和全磷8项指标,指标权重为各自公因子方差的百分比,据此测算28个桑园的土壤综合肥力指数平均值为0.25,变幅为0.18～0.34,可划分为高、较高、中等和偏低4个肥力等级,各等级桑园的比率分别为21.4%、25.0%、39.3%及14.3%。采用上述数值化综合评价与分析方法,可提高土壤肥力评价的定量化水平和科学性,减少评价过程中主观因素的影响。今后应根据桑树生长需求规范桑园土壤肥力丰缺标准及隶属度函数阈值,形成更加全面、客观、科学的评价标准。  相似文献   

2.
秦皇岛市草坪土壤肥力数值化综合评价与对策研究   总被引：2，自引：0，他引：2  
以秦皇岛市草坪土壤为例,对土壤的理化性质进行了室内分析,并根据各肥力因子的植物效应建立了相应的隶属度函数,计算出各评价指标的隶属度值;利用主成分分析法,确定各评价指标的权重,通过模糊数学法对土壤肥力进行了综合评价。结果表明,秦皇岛市草坪土壤综合肥力水平较低,主要限制因子为容重、有机质、碱解氮、速效钾。评价结果与草坪草生长状况相一致,表明该评价方法能准确、客观地评价草坪土壤的肥力水平,具有一定的应用价值。针对评价结果得出的土壤肥力限制因子,提出了提高土壤肥力的管理措施,对秦皇岛市草坪土壤的维护和治理提供了重要的指导和参考依据。  相似文献   

3.
城市草坪土壤肥力综合评价   总被引：6，自引：0，他引：6  
本文以河北科技师范学院昌黎校区草坪土壤为例,测定分析了土壤容重、pH值、阳离子交换量(CEC)、全盐含量、有机质、碱解氮、速效磷、速效钾等理化性质,并对土壤各肥力因子进行了数值化处理。通过隶属度函数和偏相关分析,确定了各肥力因子的隶属度值及其权重,并利用模糊数学评价方法对土壤肥力进行了综合评价。研究结果显示,河北科技师范学院昌黎校区草坪土壤综合肥力水平低,与草坪质量状况相吻合,表明该评价方法具有可行性,有助于科学、合理、准确地评价城市草坪土壤肥力状况,提高土壤肥力,改善草坪质量。  相似文献   

4.
针对川西北牧区土壤养分不均、土壤肥力下降、牧草产量不稳等问题,以红原县为例,研究评价其土壤养分和土壤肥力状况,探讨科学施肥及土壤养分诊断,以期为川西北牧区人工种草科学平衡施肥提供依据。通过采集和检验分析典型土壤样品,从土壤养分盈缺入手,采用内梅罗综合指数法评价了土壤综合肥力状况。结果表明:土壤pH值为6.28,为弱酸性,有机质含量为65.05g·kg-1,全氮含量为3.41g·kg-1,全磷含量为1.02g·kg-1,全钾含量为16.65g·kg-1,碱解氮含量为346.50mg·kg-1,有效磷含量为2.05mg·kg-1,速效钾含量为199.50mg·kg-1,综合评价土壤肥力指数为2.30,对照肥力评价状况为一般等级。该地区土壤综合肥力处于一般偏上,具体表现为磷、钾素缺乏,有机质、氮素丰富。应以氮肥为主,氮磷结合,适当补充钾肥,配施微肥的方法进行科学施肥。  相似文献   

5.
以祁连山中段青海云杉林土壤为研究对象,分析了自然状态下森林土壤养分各项指标含量与肥力之间的关系。结果表明:研究区青海云杉林土壤理化性质指标值相对较适宜林分生长,有机质含量与全氮、全钾、全磷、铵态氮、硝态氮都存在很高的相关关系,同时全氮与铵态氮、硝态氮也存在很高的相关关系;采用多元统计的主成分分析法对土壤肥力进行综合评价,得出土壤肥力指标前2个主成分的累计贡献率为99.298%,有机质、全钾、全磷、硝态氮、铵态氮等代表了研究区土壤自然肥力的水平,对土壤肥力有正向负荷;土壤肥力模糊综合评价结果为高。  相似文献   

6.
[目的]测定新疆伊犁地区肉牛养殖场的土壤环境指标,评价肉牛养殖场的土壤环境质量状况。[方法]在4个养殖场具有代表性的采样点采集土壤样本,对其有害物质(总Pb、总As、总Hg、总Cd、总Cr)的含量进行测定,并对养殖场土壤质量进行分析评价。[结果]4个肉牛养殖场土壤中总Cr、总Pb、总As、总Hg、总Cd的平均值分别为29.352、34.644、0.250、0.138、0.550 mg/kg,都低于《畜禽养殖产地环境评价规范》(HJ 568-2010)所规定的浓度限值。[结论]4个肉牛养殖场土壤环境质量属于清洁级别,符合肉牛养殖土壤环境质量标准。  相似文献   

7.
<正>TOPSIS(Technique for Order Preference by Similarity to Ideal Solution)法是一种常见的综合评价方法,因其具有不用对指标赋权、计算简便、结果合理、应用灵活等特点,能充分利用样本资料所反映的统计信息对参评对象做出评价,被广泛应用于各行业生产状况及各种指标的评价分析。鉴于此,本文利用TOPSIS法的计算原理,建立黑龙江省垦区畜牧业生产状况评价模型,应用于黑龙江省垦区各管局的畜牧业生产状况的评价分析,对各管局的畜牧生产水  相似文献   

8.
针对以往草坪质量评价方法存在人为权重赋值误差,以及计算繁琐等方面的问题,提出了对草坪坪用质量指标综合评价的投影寻踪等级评价方法。该方法依据标准样本自身的数据特性寻求最佳投影方向,通过最佳投影方向与评价指标的线性投影得到投影指标值,依据投影指标值对样本进行统一评价和分类,并利用最佳投影方向判断各评价指标对综合评价目标的贡献大小。应用该方法较好地对西藏林芝地区野生波伐早熟禾(Poa poophagorum Bor)的坪用等级进行了评价,并对单一坪用指标对坪用质量综合评价的贡献进行了分析,波伐早熟禾草坪等级为4级;此评价方法精确度较高,分析结果平均绝对误差为0.15%,平均相对误差为6.21%。  相似文献   

9.
为探究永兴县冰糖橙果园土壤肥力特征及其综合性状,为果园土壤改良和合理施肥提供依据。在永兴县冰糖橙主产区采集了284处具有代表性果园表层土壤(0-40cm),测定了土壤有机质、pH值、全氮、碱解氮、有效磷、速效钾、缓效钾等养分指标,运用模糊综合评判法,对永兴县冰糖橙果园及其北、中和南3个区域土壤肥力质量进行了综合评价,并比较3个区域的土壤肥力差异特征。结果表明：永兴县冰糖橙果园土壤肥力为中等水平,土壤为酸性,平均仅5.47;有机质含量较丰富,为较高等水平,平均为25g/kg;土壤全氮含量为较高等水平,平均为1.86g/kg,碱解氮含量为中等水平,平均109mg/kg;有效磷平均含量25.2mg/kg,为中等水平;缓效钾含量偏低,为较低等水平,平均132mg/kg;速效钾含量处于较高等水平,平均153mg/kg。果园的3个区域土壤综合肥力属于中等偏下水平,受地形地貌、成土母质、果园管理及其他因素影响,中部区果园综合肥力高于北部和南部果园。  相似文献   

10.
应用模糊综合评判方法 ,选取雅安市名山县20个地点,监测土壤含水率、大气质量、土壤退化度、水体质量、土壤肥力、农药残留量、重金属含量、植物多样性和无脊椎动物9项因素,进行农田生态系统环境安全状况评价与分析。结果表明,该地区北部、东北部和南部农田生态系统环境安全风险度较高,其中风险度达到风险级需要预警的耕地面积占总耕地面积的16.55%,风险级为敏感或敏感以下的耕地面积占总耕地面积的83.45%。  相似文献   

11.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

12.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

13.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

14.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

15.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

16.
Comparison of different tests to diagnose feline infectious peritonitis   总被引：1，自引：0，他引：1  
  相似文献   

17.
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.  相似文献   

18.
Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein  相似文献   

19.
正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in  相似文献   

20.
Tropical Animal Health and Production -  相似文献   

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