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1.
同工不同酬是一种很普遍的社会现象,在图书馆也不例外,它与公平背道而驰,有悖于和谐社会的理念,造成图书馆运转效率低下,人才流失,人际关系紧张,因此很有必要采取相应的措施消除这样的现象。  相似文献   
2.
\t\t\t\t\t目的\t\t\t\t\t研究云南省盈江县的耕地生产潜力及产量差,为该区域的土地利用、资源保障、经济发展等提供重要的支撑作用。\t\t\t\t\t\t\t\t\t\t\t\t\t方法\t\t\t\t\t以盈江县耕地地力调查数据为基础,利用ArcGIS 10.0软件对基础数据进行转换、叠加及分析,重点关注研究区域中耕地地块的属性,利用生产潜力计算模型分析盈江县耕地生产潜力,并根据耕地的实际产量数据分析其产量差。\t\t\t\t\t\t\t\t\t\t\t\t\t结果\t\t\t\t\t盈江县耕地生产潜力主要分布在9.46~24.87 t/hm2之间,县域均值为14.17 t/hm2,区域差异较大。产量差分布在16.18%~87.58%之间,县域均值为64.30%。从空间分布角度,县域内区域间的耕地生产潜力及产量差呈现出较大的区域差异,具有明显的区域分布特征,即生产潜力较高的区域主要分布在太平镇、平原镇、弄璋镇等大盈江流域,产量差较高的区域主要分布在盏西镇、勐弄镇、昔马镇等盈江县中、北部区域。\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t结论\t\t\t\t\t利用ArcGIS对耕地生产潜力及产量差研究,其研究数据可以根据耕地地力调查周期、耕地的实际产量及时的更新,研究结果贴合研究区域实际情况,对于提高农业产出、促进区域农业可持续发展具有积极的意义。\t\t\t\t  相似文献   
3.
近年在沙糖橘主要产区广东省肇庆市和云浮市,沙糖橘囚黄化而导致低产、果实品质下降、树体早衰甚至死亡的现象剧增。试验处理800株沙糖橘,死亡16株,死亡率2%;对照120株,死亡91株,死亡率75.8%。研究表明:根据沙糖橘生物学特性和年生长发育规律,通过科学管理增强树势,能够减少沙糖橘黄化死亡,延长树体寿命。  相似文献   
4.
基于师法自然的理念,提出了发展学基本原理(生态基础原理,民生至上原理,和谐发展原理),社会组织的职能与责任,劳动公平与劳动计量,社会规范的生命周期与进化,社会发展多元化、去货币化、减商化理论,和谐社会评价指标体系,社会系统的分析评价方法与社会系统管理理论与方法,分析了我国农村当前发展障碍并提出了对策。  相似文献   
5.
6.
There are at least 70 species of mole crickets (Orthoptera: Gryllotalpidae). Some are rare, others are innocuous, and a few are important pests. These soil-dwelling pests damage underground parts of a long list of cultivated plants. Although tillage and flooding are used successfully in some situations to bring these pests to the soil surface and expose them to vertebrate and other predators, chemical pesticides are widely used against them. Knowledge of their life history is used to time application of chemical treatments to save money, but is not used as widely as it might be. Classical biological control has been used against immigrant mole crickets in Hawaii, Puerto Rico, and the southern USA. In Florida, three Scapteriscus species from South America cause major damage to pastures and turf and are targets of a classical biological control program. Population levels of two of the pest species have been reduced substantially in Florida by establishment of a tachinid fly (Ormia depleta) and a steinernematid nematode (Steinernema scapterisci) from South America. The nematode also functions as a biopesticide. Managers of pastures and turf in Florida have thus far derived benefit from these classical biological control agents without understanding their function: use of chemicals is reduced when mole cricket populations are lower due to action of these organisms. Future enhancement of the action of O. depleta and of a sphecid wasp (Larra bicolor, which also was introduced from South America) probably will demand deliberate planting of nectar sources for adults of these biological control agents, and the advantage will be to managers who adopt such a strategy. Chemical pesticide use is strongly promoted by a large chemical industry, whereas biopesticidal use has thus far been little promoted and sales have been few. Even managers who do not change their simple strategy of pesticide use in response to damage by mole crickets, and have no knowledge of the differing life cycles of the three Scapteriscus species or of the presence and action of the classical biological control agents, will derive benefit as these biological control agents (and a predatory beetle which has not yet been released) increase their distribution.  相似文献   
7.
BACKGROUND: For an oil adjuvant to enhance uptake of a particulate active ingredient (AI), it is hypothesised that closer association between the two should result in higher uptake. Accordingly, factors important for the spray deposit size on grapevine leaves have been investigated for a series of model suspoemulsion formulations containing colloidal crystalline AI or fluorescent pigment particles and an emulsion of an oil adjuvant with different degrees of wetting and different spray volumes. RESULTS: Low spray volumes (<100 L ha(-1)) produced small deposits with high particle-adjuvant association. Complementary uptake studies showed increased uptake with decreasing deposit size, in agreement with the above hypothesis. Higher spray volumes produced larger deposits that consisted of annuli formed by pinning of the contact line by particles. Low surfactant concentrations favoured particles in the annulus and adjuvant separated in the centre. Intermediate surfactant concentrations produced annuli containing both particles and adjuvant, while with high surfactant concentrations the deposits were large with few annuli.CONCLUSIONS: Small deposits result in high AI-adjuvant association. With larger deposits, annulus structures allow for enhanced AI-adjuvant association (5-20 times greater). The formation of annuli appears to be important in enhancing the biodelivery of particulate AIs in adjuvant-containing suspoemulsion formulations at intermediate spray volumes.  相似文献   
8.
Experiments in controlled environments were carried out to determine the effects of temperature and leaf wetness duration on infection of oilseed rape leaves by conidia of the light leaf spot pathogen, Pyrenopeziza brassicae . Visible spore pustules developed on leaves of cv. Bristol inoculated with P. brassicae conidia at temperatures from 4 to 20°C, but not at 24°C; spore pustules developed when the leaf wetness duration after inoculation was longer than or equal to approximately 6 h at 12–20°C, 10 h at 8°C, 16 h at 6°C or 24 h at 4°C. On leaves of cvs. Capricorn or Cobra, light leaf spot symptoms developed at 8 and 16°C when the leaf wetness duration after inoculation was greater than 3 or 24 h, respectively. The latent period (the time period from inoculation to first spore pustules) of P. brassicae on cv. Bristol was, on average, approximately 10 days at 16°C when leaf wetness duration was 24 h, and increased to approximately 12 days as temperature increased to 20°C and to 26 days as temperature decreased to 4°C. At 8°C, an increase in leaf wetness duration from 10 to 72 h decreased the latent period from approximately 25 to 16 days; at 6°C, an increase in leaf wetness duration from 16 to 72 h decreased the latent period from approximately 23 to 17 days. The numbers of conidia produced were greatest at 12–16°C, and decreased as temperature decreased to 8°C or increased to 20°C. At temperatures from 8 to 20°C, an increase in leaf wetness duration from 6 to 24 h increased the production of conidia. There were linear relationships between the number of conidia produced on a leaf and the proportion of the leaf area covered by 'lesions' (both log10-transformed) at different temperatures.  相似文献   
9.
用生态人类学的观点解读黄佤的森林崇拜,可以看到黄佤森林崇拜反映了人与自然和谐发展的生态文化观,对当地生态环境的保护以及提高社区成员的生态保护意识起了重要作用。对黄佤森林崇拜所蕴含的生态保护思想进行挖掘和整理,能为解决当今的生态问题提供一些启示。  相似文献   
10.
在新疆干旱区,由于暖季沙漠增温效应的影响,与沙漠相邻绿洲区的热量资源相对优越,为植棉提供了有利条件。但随着时空变化,绿洲棉花热量生产潜力也呈现出相应的分异规律。本文以新疆北疆玛河流域石河子平原绿洲区为例,将绿洲与沙漠联系起来考虑,分析了距沙漠不同距离梯度的绿洲区棉花热量生产潜力。结果表明:石河子平原绿洲区内,距离沙漠最近区与最远区之间棉花热量生产潜力相差389Kg/hm2,绿洲与沙漠的距离平均每增加10Km,热量生产潜力下降43Kg/hm2。暖季沙漠增温效应对绿洲棉花的热量生产潜力影响明显,沙漠对相邻绿洲区的农业生产有着正面影响,起到了除太阳外第二个热量源的作用。  相似文献   
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