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11.
无角美利奴亲本母羊生产性能与血液生化指标的相关性   总被引:1,自引:0,他引:1  
对87只无角美利奴亲本母羊的生产性能及其血液生化指标进行了测试分析,试验结果表明,毛长,毛密,体重与其血清无机磷,血清钙磷乘积,血清总蛋白,血清白蛋白、胆固醇、黄疽指数呈极显著正相关;与血清钠、胡萝卜素,a2球蛋白呈显著正相关;而与血清磨香草酚浊度呈极显著负相关;与硫酸锌浊度、血清谷草转氨酶活力呈显著负相关;与其年龄呈显著负相关。  相似文献   
12.
朱蔓莉  周明 《安徽农业科学》2012,40(26):13152-13154
分析了饲料企业的现状,提出了基于产品链的指标分解模型。针对企业实际情况,研究了企业内部管理的各类数据,建立了产品链,给出了实现基于产品链的指标分解模型的系统解决方案,以达到生产控制管理精细化的目的。  相似文献   
13.
黄陵县土壤养分丰缺指标和施肥指标体系制定   总被引:2,自引:0,他引:2  
本文就黄陵玉米地土壤养分丰缺指标和施肥指标体系制定进行探究,目的在于对该区土壤养分进行评价,为当地农业生产提供新的施肥指标,为高产、高效、土壤培肥和农环保护提供相应理论指导。  相似文献   
14.
15.
This paper presents a different approach to the welfare of working horses through the indicators of good welfare, their interrelations and their relationships with the type of work performed by the horses. 697 working horses were assessed by using observation, behavioural tests, clinical exams and questionnaires. The correlated results highlight the complex and multiple interrelations between the good welfare indicators, showing once again that animal welfare is under the influence of all its three dimensions (physical and emotional wellbeing and naturalness). In working horses, the heavier the work they perform is, the more important it is for horse owners/breeders/farmers to fulfil their inherent needs so as to help them cope with the multiple specific risks imposed by their work.  相似文献   
16.
We use an individual-based model to assess the conservation objectives for knot Calidris canutus L. and oystercatcher Haematopus ostralegus L. on the Burry Inlet Special Protection Area (SPA), UK. Population monitoring has identified a decline in oystercatcher numbers, but cannot determine whether this is due to a decline in site quality. Long term data on cockle stocks show that the biomass of the large-sized cockles consumed by oystercatcher declined after 2004, whereas a similar decline was not observed in the smaller cockles consumed by knot. The model postdicts that during the winters of 2005/2006 to 2008/2009 the site was unable to support the number of oystercatcher present at the time it was designated (i.e. the SPA population). Large cockle biomass remained low during 2009/2010, but increases in mussel biomass meant that the model postdicted that the site could support the SPA population of oystercatcher. Knot food supplies remained high during most years, except 2008/2009 during which the model postdicted that the SPA population could not be supported. The model postdicted that the stock reserved for oystercatchers after shellfishing needed to be 2-4 times the amount consumed by the birds in order to support the bird population. We recommend that where necessary, the conservation objectives of waterbirds should be assessed using a combination of thorough population size and behaviour monitoring to identify sites with population declines, and individual-based modelling on these sites to determine whether reduction in site quality may contribute to the site-specific population decline.  相似文献   
17.
南亚热带主要果树冻(寒)害低温指标的确定   总被引:4,自引:0,他引:4  
根据历史气候和冻(寒)害灾情资料、2007/2008、2008/2009年冬季盆栽移放试验和典型年考察资料,以及冻(寒)害形态学标准,采用数理统计和对比印证方法,对南亚热带主要果树冻(寒)害低温指标进行研究。确定了几种主要南亚热带果树的轻、中、重、严重冻(寒)害低温指标,结果分别为龙眼:-1.5~0℃、-2.5~-1.5℃、-3.5~-2.5℃、<-3.5℃;荔枝:-2.0~0℃、-3.0~-2.0℃、-4.0~-3.0℃、<-4.0℃;香蕉:3.0~5.0℃、1.0~3.0℃、-1.0~1.0℃、<-1.0℃。结果可为果树冻害监测预警及避冻区划提供参考。  相似文献   
18.

The intent of long-term ecological monitoring is to document changes in important properties of biological communities. At the least, a long-term monitoring system should be designed to detect long-term trends in three key attributes: soil and site stability, hydrologic function, and the biotic integrity of the system. There are four basic guidelines for developing integrated soil-vegetation monitoring systems for rangelands. These are: (1) identifying a suite of indicators which are consistently correlated with the functional status of one or more critical ecosystem processes and/or properties; (2) selecting base indicators on site specific objectives and resource concerns, and inherent soil and site characteristics; (3) using spatial variability in developing and interpreting indicators to make them more representative of ecological processes; and (4) interpreting indicators in the context of an understanding of dynamic, nonlinear ecological processes. To the extent possible, indicators should reflect early changes in ecological processes and indicate that a more significant change is likely to occur. In addition to these guidelines, measurements included in long-term monitoring systems should be rapidly applied, simple to understand, inexpensive to use, and quantitatively repeatable.  相似文献   
19.
Soil is an essential resource for life and its properties are susceptible to be modified by tillage systems. The impact of management practices on soil functions can be assessed through a soil quality index. It is interesting to assess soil quality in different soil types. Therefore, the aim of this study was to determine the soil quality index of a Paleudult under different management conditions and sunflower culture. The experiment was carried out in Botucatu (SP, Brazil), in an 11-year non-tilled area used for growing soybean and maize during summer and black oat or triticale in winter. Four management systems were considered: no-tillage with a hoe planter (NTh), no-tillage with a double-disk planter (NTd), reduced tillage (RT) and conventional tillage (CT). Soil samples were taken from the planting lines at harvest time. To determine the soil quality indices, following the methodology proposed by Karlen and Stott (1994), three main soil functions were assessed: soil capacity for root development, water storage capacity of the soil and nutrient supply capacity of the soil. The studied Paleudult was considered a soil with good quality under all the observed management systems. However, the soil quality indices varied between treatments being 0.64, 0.68, 0.86 and 0.79 under NTh, NTd, RT and CT, respectively. Physical attributes such as resistance to penetration and macroporosity increased the soil quality index in RT and CT compared to NTh and NTd. The soil quality indices obtained suggested that the evaluated soil is adequate for sunflower production under our study conditions. In view of the SQI values, RT is the most suitable management for this site since it preserves soil quality and provides an acceptable sunflower yield.  相似文献   
20.
Developing socioeconomic indicators for ecosystem-based fisheries management is particularly important. This is because socioeconomic factors have direct effects on ecosystems, and ecosystems have direct effects on socioeconomic factors. Therefore, it is imperative that socioeconomic indicators are developed and evaluated in order to predict changes in ecosystems and to provide advice for effective fisheries management. In this study, socioeconomic indicators have been developed to be combined with biological and ecological indicators, in order to conduct the ecosystem-based fisheries assessment. In terms of socioeconomic indicators, five socioeconomic criteria were considered as important attributes of socioeconomic changes. These were economic production, business conditions, levels of income, the state of the market, and levels of employment. In order to establish reference points for the evaluation of indicators, target reference points and limit reference points were set through a comparison with other industries or other fisheries rather than by using the Traffic Light System (TLS) method, which has been used in many previous studies. In addition, on the basis of the application of developed indicators and reference points to the Korean large purse seine fishery, the socioeconomic conditions of the fishery and the usefulness of the indicators were evaluated and management implications were discussed.  相似文献   
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