Expectations for population growth at new breeding locations for the vulnerable New Zealand sea lion (Phocarctos hookeri) using a simulation model

Management plans for threatened or recovering large vertebrate species that are increasing in population size and range focus on the establishment of viable populations within set temporal limits. New Zealand (Hookers) sea lions (Phocarctos hookeri) were declared a threatened species in 1997, and New Zealand legislation requires that threatened species of marine mammals must be managed to reduce human-induced mortality and achieve a non-threatened status within 20 years. The present breeding distribution of P. hookeri is highly localised, with over 95% of total annual pup production located at Auckland Islands and almost all of the remainder at Campbell Island. Breeding elsewhere has been ephemeral or restricted to <10 adult females. The only recorded sustainable breeding at a new location has been at Otago, South Island, New Zealand. This breeding population consisted of a total of four breeding females in 2002 and is derived from one immigrant female that gave birth to her first pup in the 1993/1994 breeding season. The New Zealand Department of Conservation management plan specifies that to achieve a non-threatened status P. hookeri (1) at Otago must increase in the number of breeding females to ?10, and (2) must establish ?two new breeding locations within the 20-year time frame, each with ?10 breeding females. This study 1) projects the population growth trends at a new location (Otago) to see if it will achieve ?10 breeding females within the legislated time frame, and (2) examines the likelihood that other breeding locations will establish elsewhere given the demographic information available for this species. We present 20 deterministic and three stochastic Leslie matrix model scenarios for female population growth for the initial years following the start of breeding at a new location. Our results indicate that (1) a new breeding population derived from one immigrant female is unlikely to reach 10 breeding females in 20 years; this duration is more likely to be 23-41 years (deterministic models) or 23-26 years (stochastic model), (2) the likelihood of two new sites establishing within 20 years is unquantifiable, but the probability is low, and (3) if the legislated outcome and time limit are not revised in the population management plan, the feasibility and effectiveness of re-locating young females could be investigated.     

Increase in Growth,Productivity and Nutritional Status of Wheat (Triticum aestivum L.) and enrichment in Soil Microbial Population Applied with Biofertilizers Entrapped with Organic Matrix

To find effective alternatives to reduce the application of conventional urea (CU), a conventional biofertilizer (CB) preparation (charcoal mixed Azotobacter chroococcum and Bacillus subtilis) and the same biofertilizers entrapped in an organic matrix consisting of cow dung, rice bran, dried powder of neem leaves, and clay soil in 1:1:1:1 ratio and 25% (w/w) saresh (plant gum of Acacia sp.), named as super granules of biofertilizers (SGBF) were applied to cultivate wheat (Triticum aestivum L. cv. ‘WH-711’) in experimental plots. The results revealed that the efficacy of commercially available charcoal mixed biofertilizers could not prove as effective alternative to CU, whereas the same dose of biofertilizers entrapped in the organic matrix, SGBF, resulted in a significant increase in growth and productivity of wheat. It appears that SGBF prepared and applied in this study is an effective organic alternative to the urea for wheat cultivation in semi-arid subtropical agro-ecosystems.     

University Outreach in the Twenty-First Century

ABSTRACT

Educational outreach, especially from land-grant universities, will have a more prominent, visible role in the twenty-first century. There is a widespread belief among university leaders that the effect of universities must reach beyond the limits of the campus to positively influence the social, cultural and economic well-being of constituents. Enhanced outreach efforts will involve all academic units and provide appropriate faculty rewards for their accomplishments. Existing extension/outreach organizations such as Cooperative Extension Services will expand their base to draw from the total university expertise and knowledge base. Funding will be a challenge as public resources become less available. Distance education through satellite communications and other advanced technology will be a growing part of education outreach.     

常熟市水体氮负荷对土地利用方式的响应

为研究水环境变化对土地利用方式的响应,以常熟地区为例,利用ArcGIS10.0空间分析功能和SPSS相关性分析方法,对常熟市各土地利用类型和水体总氮含量进行了分析。结果表明:1990—2010年间常熟地区耕地和水域面积在持续缩减,建设用地和林地面积在增加;各土类状态指数(Di)大小依次为:建设用地林地草地耕地水域;建设用地面积的增加主要占据的是耕地和水域,水域面积的缩减主要被耕地占用;耕地面积与水体总氮含量呈显著性负相关关系(r=–0.959*,P0.05),说明种植型污染贡献比例在下降;林草地与水体总氮含量无显著相关性;建设用地与水体总氮含量呈显著性正相关关系(r=0.929*,P0.05),说明建设用地造成了点源污染。     

紫叶矮樱不同基质育苗比较试验

以炉渣、锯末、菇渣废料、鸡粪、羊粪、田园土分别按照不同体积比配制9种供试基质,对紫叶矮樱进行处理,研究不同基质养分对紫叶矮樱苗木株高及成品苗质量的影响.结果表明:G6基质(田园土∶炉渣∶菇渣废料∶鸡粪=6∶3∶0.5∶0.5)为最佳栽培基质.     

3x+1问题的若干性质

从一个特殊的角度描述3x 1问题,引入了部分新的概念,建立了3x 1问题的等价命题,得到了关于3x 1问题特别是数列{fk(x)|k∈Z }的一部分性质.     

Advice in spite of great uncertainty: assessing and addressing bycatch of small fishes with limited data using Stellifer illecebrosus as a case study

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Practical Method of Form-finding of Semi-rigid Structures

Based on the discussion of the simulation for the cable prestress, the rigidity theory was used to identify the geometrical dimensions of semi-rigid structures in zero state. When the structural geometry in initial state is given, the geometrical dimension in zero state is determined by the initial prestress distribution. The contribution-matrix method is firstly applied to get the initial lack of fit. However, the influencing factor of initial lack of fit on the displacement of control point is linear superposition, that is, the structural response is linear, and it is irreconcilable with the geometry nonlinear of semi-rigid structure. In order to reduce the error of nonlinear structural response, the influencing factor in the contribution-matrix method is revised, and modified contribution-matrix method is put forward. Programs by ANSYS parameter design language APDL are worked out for the form-finding analysis of beam-string structure of a practical project. The numerical results show that the modified contribution-matrix method reduces the errors of the assumption of structural linear response. And it can be applied to the form-finding of semi-rigid structures with small stiffness.     

观赏棕榈播种育苗关键技术研究

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Scale-dependent habitat use in three species of prairie wetland birds

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