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721.
樊省状 《山东地质》2008,24(2):21-23
为实现矿产资源储量管理网络实时查询功能,在目前国土资源部金土工程的储量管理软件的基础上,开发出了“基于C/S的矿产资源开发储量管理信息系统”。该系统采用了结构化的程序设计方法,操作系统平台采用了MS Windows系统,程序开发平台采用了Borland公司Delphi,数据库的查询语言采用标准SQL查询语言,主要实现了矿产资源开发和储量数据的综合查询和汇总功能。  相似文献   
722.
Efforts to reverse declines in native grasslands benefit from agricultural policies that encourage private land conservation. The U.S. Department of Agriculture’s Conservation Reserve Program (CRP) improved conservation across landscapes but enrollment has declined. We used sequential exploratory mixed methods to compare landowner and conservation practitioners’ perceptions, evaluate perceived benefits, and identify potential improvements to CRP. Focus groups of practitioners informed a quantitative survey of landowners who had properties >160 total acres in Nebraska. Results suggest potential misalignment in perceptions between practitioners and landowners. Practitioners were concerned that conservation, especially of wildlife, was secondary to profit. But the majority of landowners valued CRP-related ecosystem services, including native pollinators. Practitioners posited that younger landowners were primarily profit motivated, but CRP enrollment did not differ by demographics. Practitioners and landowners identified rule complexity as a major challenge and practitioner–landowner relationships as critical to success. Findings suggest that practitioners may underestimate non-economic motivations and illuminate opportunities to encourage private land conservation.  相似文献   
723.
The Royal Belum forest reserve is one of the oldest tropical rainforests in the world and it is one of the largest virgin forest reserves in Malaysia. However, not many studies have been conducted to understand the ecology of this forest. In this study we estimated the aboveground biomass (AGB) of the forest using diameter at breast height (DBH) and height of trees (h ), tree species and hemispherical photographs of tree canopy. We estimated AGB using five allometric equations. Our results demonstrated that the AGB given by the one tree species specific allometric equation does not show any significant differences from the values given by the non‐tree species specific allometric equations at tree and plot levels. The AGB of Intsia bijuga species, Koompassia malaccensis species and Shorea genera were comparatively higher, owing to their greater wood density, DBH and h. This has added importance because some of these species are categorized as threatened species. Our results demonstrated that mean AGB values in this forest (293.16 t ha‐1) are the highest compared to some studies of other areas in Malaysia, tropical Africa and tropical Bazilian Amazonia, implying that the Royal Belum forest reserve, is an important carbon reservoir.  相似文献   
724.
Marine reserves can create both benefits and costs to fishers. This article explores the perceptions of fishers in Kenya and Seychelles about displacement, spillover, and overall impacts of local marine reserves on their livelihoods. We test whether these perceptions are different among fishers from different geographic and socioeconomic conditions. Sixty-six percent of fishers had been displaced from marine reserves or coastal development and 90% believed they had caught fishes that spilled over from marine reserves. Poorer fishers in Kenya were both displaced from, and also felt like they benefited from, marine reserves. This highlights how people's experiences with marine reserves, both positive and negative, are affected by a range of social considerations that may not be incorporated in typical evaluations of ecological and economic marine reserve success.  相似文献   
725.
随着天津市土地整理储备业务的发展,在野外实时、动态地查阅土地整理地块信息的应用需求越来越强烈。针对这种应用需求,本文在天津市土地整理中心现有信息系统的基础上,设计并实现了天津市土地整理储备移动监管平台,解决了外业土地调查过程中查阅资料困难及土地整理过程监督管理无依据等问题。  相似文献   
726.
利用2009-2013年上海市加密观测自动站降水资料和110报警信息资料,对上海市短时强降水进行统计分析,了解其地理分布特征、概率分布特点的同时,找出降水极端性与暴雨红色预警标准的对应关系,以及110报警次数与短时强降水的关系。结果表明:1)自动站1 h雨量≥30 mm、≥50 mm和3 h雨量≥50 mm、≥100 mm的5 a累计频数的大值区基本集中在市区及其周边地区,郊区次数明显减少,出现次数最多的是3 h雨量≥50 mm的情况,出现次数最少的为3 h雨量≥100 mm的情况。2)从不同降水强度的发生概率分布来看,郊区弱降水发生概率大于市区的,市区强降水(1 h雨量≥25 mm)发生概率大于郊区的。3)对流降水情况下,降水累积概率为1%时,对应的1 h雨量市区为63.6 mm、郊区为58.7 mm,接近暴雨红色预警标准;对应的3 h雨量市区为90.8 mm、郊区为86.8 mm,较暴雨红色预警标准的阈值小。4)报警次数与降水量的关系:1当1 h雨量40 mm或3 h雨量60mm时,报警次数变化不大,基本在10次以下;当1 h雨量≥40 mm或3 h雨量≥60 mm时,报警次数逐渐增多,大部分在20次以上;当1 h雨量≥60 mm(达到暴雨红色预警标准)、3 h雨量≥80 mm(未达到暴雨红色预警标准)时,报警次数明显增多,基本超过30次,最多达100次以上。从报警次数的角度来看,暴雨红色预警的3 h标准设定为80~90 mm更合适。2当逐1 h和逐3 h雨量不是很大、但累积降水量较大(特别是累积降水量超过100 mm)时,报警次数急剧增多,很多超过100次,说明报警次数还与降水的持续时间有关。3当累积降水量、逐1 h和逐3 h雨量都增加时,报警次数增加最快。4报警次数的极值并非都出现在逐1 h和逐3 h雨量大值时,在1 h雨强不是很强,但降水持续时间长,累积降水量大的时候,也十分容易出现报警极值。  相似文献   
727.
Measuring the ‘level of compliance’ has emerged as a key performance indicator for MPA success internationally. Accurate interpretation of quantitative and qualitative compliance data is critical for determining which compliance activities contribute to specific management outcomes. To demonstrate the value of enforcement data in effective MPA management, more than 5000 enforcement actions from 2007 to 2013 from five New South Wales (NSW) Marine Parks were analysed. Specifically, it was tested whether through time: (i) the number of enforcement actions standardised by surveillance effort declined-indicating that ‘general deterrence’ was being achieved; (ii) the number of repeat offenders decreased-indicating that ‘specific deterrence’ was being achieved; (iii) the number of ‘local community’ enforcement actions standardised by surveillance effort declined-indicating growing support for marine parks was being achieved at the community level; and (iv) the percentage of young offenders (<25 yr) had declined-indicating that education programs targeting young adults were successful. Results indicated that general deterrence was not being achieved, with offence rates being relatively stable between years. In contrast, compliance measures were achieving individual deterrence, with the percentage of repeat offenders being very low (0.13–0.83%). Although compliance strategies may be making some progress in improving local compliance in some marine parks, the overall offence rate of local communities was concerning. The data suggested that there were major differences in compliance rates among age groups of offenders over time, although the percentage of young offenders declined over time in three marine parks. Over the six-year data collection period, there was no discernable improvement in compliance rates in most NSW Marine Parks. Overall, the significant value of collecting and analysing information on enforcement activities for MPAs was demonstrated, an often neglected aspect of their management world-wide.  相似文献   
728.
Previous estimates of the land area available for future cropland expansion relied on global-scale climate, soil and terrain data. They did not include a range of constraints and tradeoffs associated with land conversion. As a result, estimates of the global land reserve have been high. Here we adjust these estimates for the aforementioned constraints and tradeoffs. We define potentially available cropland as the moderately to highly productive land that could be used in the coming years for rainfed farming, with low to moderate capital investments, and that is not under intact mature forests, legally protected, or already intensively managed. This productive land is underutilized rather than unused as it has ecological or social functions. We also define potentially available cropland that accounts for trade-offs between gains in agricultural production and losses in ecosystem and social services from intensified agriculture, to include only the potentially available cropland that would entail low ecological and social costs with conversion to cropland. In contrast to previous studies, we adopt a “bottom-up” approach by analyzing detailed, fine scale observations with expert knowledge for six countries or regions that are often assumed to include most of potentially available cropland. We conclude first that there is substantially less potential additional cropland than is generally assumed once constraints and trade offs are taken into account, and secondly that converting land is always associated with significant social and ecological costs. Future expansion of agricultural production will encounter a complex landscape of competing demands and tradeoffs.  相似文献   
729.
随着自然保护地整合优化预案的实施及勘界立标工作的进展,对勘界成果的现势性和准确性要求日益提高。为解决传统勘界工作中存在的监测技术落后、工作量繁多、成果界线不精确、边界不客观等问题,本文基于无人机倾斜摄影测量技术,结合Google地图和数字正射影像,通过摄影测量和实地测量相结合的方法,实现了满足精度要求的自然保护地边界快速识别和提取。以韶关市北江特种珍稀鱼类省级自然保护区为例,构建1:500实景三维模型,为"高标准打造粤北生态特别保护区,做好自然保护地优化整合工作"提供了清晰、可靠的本底数据。试验结果表明,该方法技术先进成熟,自动化程度高,能够满足保护地边界勘测的精度要求,具有广阔的探索潜力与应用前景且易于推广。  相似文献   
730.
With increasing numbers and types of nature reserves (NRs), objective evaluation and comparison of the effects of different nature NRs on conservation efforts are of great importance for protecting species diversity, ensuring reasonable national economic input, and adjusting government management schemes. Developing a method for the combined assessment of flagship or umbrella species and ecosystem quality will improve the evaluation of NRs. However, it is also important to establish a new framework for rapid evaluation of ecosystem quality, supported by the advantages of scientific, economic, and regular principles. Here, we proposed a new framework that incorporates the novel concept of ideal references into evaluation systems, which will facilitate the comparison of results from different periods and regions. Furthermore, from the perspective of making the framework as objective, rapid, and economical as possible, we recommended some key ecological indicators, such as net primary productivity, soil organic matter, plant diversity, for use in the new evaluation framework. The new framework, referred to as “ideal reference and key indicators” (IRKI), can sufficiently meet the requirements for the rapid evaluation of ecosystem quality both regionally and nationally. Furthermore, IRKI can identify the restoration potential and restoration periods of NRs, thus facilitating the rational distribution of resources and enhancing the protective effect. There are many types of NRs in China, and it is necessary to partially alter the assessment methods or parameters for different types of NRs. Overall, IRKI provides a simple, clear, and comparable framework that will strongly enhance the conservation of protected areas (PAs) and facilitate the standardization of management practices.  相似文献   
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