Preserving Population Allele Frequencies in Ex Situ Conservation Programs

Abstract: Optimization of contributions of parents to progeny by minimizing the average coancestry of the progeny is an effective strategy for maintaining genetic diversity in ex situ conservation programs, but its application on the basis of molecular markers has the negative collateral effect of homogenizing the allelic frequencies at each locus. Because one of the objectives of a conservation program is to preserve the genetic composition of the original endangered population, we devised a method in which markers are used to maintain the allele frequency distribution at each locus as closely as possible to that of the native population. Contributions of parents were obtained so as to minimize changes in allele frequency for a set of molecular markers in a population of reduced size. We used computer simulations, under a range of scenarios, to assess the effectiveness of the method in comparison with methods in which contributions of minimum coancestry are sought, either making use of molecular markers or genealogical information. Our simulations indicated that the proposed method effectively maintained the original distribution of allele frequencies, particularly under strong linkage, and maintained acceptable levels of genetic diversity in the population. Nevertheless, contributions of minimum coancestry determined from pedigree information but ignoring the genealogy previous to the conservation program, was the most effective method for maintaining allelic frequencies in realistic situations.     

Gaps in provincial decision-maker’s perception and knowledge of climate change adaptation in China

The perspectives and knowledge of decision makers, especially those at the provincial level, have great impact on the progress of climate change adaptation in China. Therefore, identifying knowledge gaps and enhancing climate adaptation awareness of decision makers at that level is very important. Based on this aim, we conducted a survey of climate change adaptation awareness among 85 administrative and management personnel from governmental departments responsible for climate change adaptation planning in five provinces. Study findings revealed that over half of respondents have knowledge of climate change adaptation measures, but the extent of understanding varied across different adaptation aspects and regions. Among the different aspects, understanding of measures related to human health protection was the lowest. A large majority of respondents indicated an eagerness to obtain knowledge and information about climate change adaptation, but the main barrier is a lack of training and learning material. When making adaptation plans or policies, the greatest obstacle expressed was a funding shortage. Information generated from this study can provide direction and guidance for training and educating provincial decision makers in order to improve the levels of adaptation planning and policy making.     

东北地区盐碱泡沼渔业开发技术

盐碱泡沼广泛分布于东北地区的中、西部，是该区域宜渔国土资源的主要类型之一．根据１９８８～１９９５年东北松辽平原农业综合开发的实践，本文以大安市试验示范区为例，初步介绍了盐碱泡沼渔业开发的６项主要技术措施，以供同类地区借鉴。     

三峡水库水位涨落带土地资源的初步研究

三峡大坝建成后,将在库区两岸形成永久性的水位涨落带。涨落带冬半年为水域,丰半年出露水面成陆,是一种具有多功能的土地资源类型,在夏半年,涨落带成陆面积大,成陆期较长,与同期丰富的光热水资源构成优势组合,使涨落带土地具有较高的生产潜力。对三峡库区水位落带土地资源的质量、数量和分布特点进行分析,在此基础上提出了合理利用的设想。     

辐射化学剂量计在强脉冲混合辐射场测定中的应用

本文讨论了将硫酸亚铁剂量计和铜－铁剂量计用于强脉冲混合辐射场测定的实验设计,利用直径２２０毫米的聚乙烯球,将硫酸亚铁剂量计的快中子响应降低到２０％以下,由它和完全暴露在中子、γ混合场中的硫酸亚铁剂量计响应之差,测量中子吸收剂量。这种方法两次实际用于强脉冲混合辐射场中子、γ吸收剂量测量,得到的结果和热释光剂量计、固体径迹探测器的测量结果进行了比较,在±２５％的误差范围内一致     

Method for determining minimum pool requirements to maintain and enhance salmonid fisheries in small Wyoming reservoirs

Methods for determination of minimum pool levels in reservoirs that consider sport fishery values are being sought by managers. We developed a technique for assessing the effects of incremental changes in minimum pool levels on potential salmonid abundance in small (<100 surface hectares at full pool) reservoirs in Wyoming managed for irrigation and municipal water supplies. The method has two components. One component is used to determine the minimum pool level needed to eliminate the risk of overwinter loss of salmonids due to low dissolved oxygen concentrations. The other component predicts the potential biomass of salmonids in reservoirs as a function of water depth and total dissolved solids concentration of the reservoir water. Application of the method is demonstrated for two reservoirs in Wyoming. The unit is jointly supported by the University of Wyoming, the Wyoming Game and Fish Department, and the US Fish and Wildlife Service.     

CHANGE IN LAKE TROPHIC STATE AND INTERNAL PHOSPHORUS RELEASE AFTER ALUMINUM SULFATE APPLICATION1

ABSTRACT: Recovery of eutrophic lakes after nutrient diversion may be delayed if the lake experiences significant internal phosphorus (p) loading to the water column. A maximum dose of aluminum sulfate, defined herein, was applied to the anaerobic sediments of the hypolimnia of two dimictic Ohio lakes following septic tank diversion, with the objective of attaining long term control of the release of phosphorus to the water column from these sediments. The results were compared to a similar, downstream, untreated lake. Total phosphorus concentration declined sharply after treatment and has remained so through 1980 for both lakes, a period of 5 and 6 years of control, respectively. Internal P loading from anaerobic, hypolimnetic sediments was partially controlled by the treatment but there are other important sources, perhaps in the littoral zone, in these lakes. Algal biomass is Smaller and water transparency has increased. Both lakes became mesotrophic after treatment, as described by the Carlson (1977) trophic state index, and remain in that improved condition to date. No deleterious side effects were observed, although one lake experienced a significant decrease in diversity of planktonic microcrustacea and a lakeward extension of the macrophyte community. This method appears to be an effective and lasting means of accelerating the recovery of a eutrophic lake following nutrient diversion.     

LAKE SUPERIOR REGULATION EFFECTS

ABSTRACT: The outflows of Lake Superior through the St. Marys River have been modified from natural conditions, initially by the construction of engineering works, such as bridges, and later by the construction of control works and the regulation of the lake. For all practical purposes, the period from 1860 to 1887 represents the natural river conditions. During the period 1888-1900 the regimen was modified by the construction of the International Railroad Bridge and the Chandler-Dunbar Power Canal. In 1901 construction began on the compensating works. Following the completion of the compensating works in August 1921, the Lake Superior outflows were regulated in accordance with the Orders of Approval, 26 and 27 May 1914. A hydrologic response model was developed to simulate the natural Lake Superior regime. The model was run for the 1860–1975 period to simulate natural Lake Superior levels and outflows. The simulated levels were compared with the recorded levels to determine the effect of regulation. It was found that regulation has resulted in a rise in Lake Superior water levels. The simulated natural outflows for the period from 1937 to 1975 were run through the Great Lakes hydrologic response model to analyze the regulation effects on Lakes Michigan-Huron, St. Clair, and Erie. The results show no long-term bias due to regulation.     

浅谈新形势下强化基层环保执法的对策

基层环境行政执法存在较为严重的有法不依、执法不严、违法不纠、以权代法等现象.通过突出环境执法宣传、提高执法能力、加强强制执行权和部门协调等方面,提出了新形势下强化基层环保执法工作的对策.     

对GA优化的湖泊富营养化评价普适公式的商榷

本文介绍了李祚泳等人提出的湖泊富营养化评价的普适公式,指出了其中的错误和遗 漏之处,以引起大家的讨论。