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841.
集约化蛋鸡场鸡粪混合液资源化无害化处理 总被引:3,自引:0,他引:3
朱锦福 《城市环境与城市生态》1992,5(1):1-6
本研究采用离心分离法、高温好氧发酵法和中温厌氧发酵对鸡粪混合液进行资源化、无害化综合处理。实验结果:鸡粪回收率53.0%~91.8%;发酵后,鸡粪含水率31%~44%;废水厌氧处理的体积负荷12.14kg·COD_(cr)/m~3·d;产沼比0.52m~3/kg·COD_(cr);甲烷含量>70%。通过综合处理,COD_cr)、BOD_5的总去除率均大于90%。实验表明,本工艺具有投资少、能耗低、费用省和效益比较明显等优点。 相似文献
842.
Efficient statistical mapping of avian count data 总被引:3,自引:0,他引:3
J.?Andrew?RoyleEmail author Christopher?K.?Wikle 《Environmental and Ecological Statistics》2005,12(2):225-243
We develop a spatial modeling framework for count data that is efficient to implement in high-dimensional prediction problems. We consider spectral parameterizations for the spatially varying mean of a Poisson model. The spectral parameterization of the spatial process is very computationally efficient, enabling effective estimation and prediction in large problems using Markov chain Monte Carlo techniques. We apply this model to creating avian relative abundance maps from North American Breeding Bird Survey (BBS) data. Variation in the ability of observers to count birds is modeled as spatially independent noise, resulting in over-dispersion relative to the Poisson assumption. This approach represents an improvement over existing approaches used for spatial modeling of BBS data which are either inefficient for continental scale modeling and prediction or fail to accommodate important distributional features of count data thus leading to inaccurate accounting of prediction uncertainty. 相似文献
843.
BERRY J. BROSI†† MICHAEL J. BALICK ROBERT WOLKOW† ROBERTA LEE‡ MARK KOSTKA§ WILLIAM RAYNOR§ ROBERT GALLEN§ ALLY RAYNOR§ PELIHTER RAYNOR§ DANA LEE LING 《Conservation biology》2007,21(3):875-879
Abstract: Erosion of traditional knowledge and practice is a serious and accelerating problem, but quantitative work on traditional knowledge loss and its importance to biodiversity conservation is lacking. We investigated traditional knowledge of canoe making, a skill heavily dependent on plant biodiversity, on Pohnpei, Federated States of Micronesia, through a survey of 180 island residents. Our results showed that there has been an intergenerational erosion of canoe-making skills. Given current trends, the present generation of Pohnpeians may be the last to retain any knowledge of this traditional craft. We also identified several correlates of knowledge loss—including Western educational level and occupation—that highlight potential avenues for skill conservation via governments, traditional leadership, and schools. These institutions could intervene to emphasize traditional knowledge, which would reinforce institutional contexts in which traditional knowledge and practice is valued. The heightened awareness of the value of biodiversity that is linked to traditional knowledge is key to biological conservation on Pohnpei and can help support local conservation programs. 相似文献
844.
土地资源可持续利用研究 总被引:2,自引:0,他引:2
坚持土地资源的可持续利用对经济发展与社会安定至关重要文章从可持结发展的概念出发介绍了土地资源可持续的含义与评价标准,分析了其实现存在的障碍,进而从认识,管理和科技角度提出了相应的对策。 相似文献
845.
Evaluation model for developing,implementing, and assessing conservation education programs: Examples from Belize and Costa Rica 总被引:1,自引:0,他引:1
Susan K. Jacobson 《Environmental management》1991,15(2):143-150
Evaluation of conservation education programs can: (1) provide accountability in demonstrating a program's worth, (2) offer
an opportunity for receiving feedback and improving programs, (3) further our understanding of the process of program development,
and (4) promote conservation education by substantiating claims about its benefits. The Planning-Process-Product systems evaluation
model provides feedback needed for making decisions about the development, implementation, and outcome of a program. Planning
evaluation was useful in assessing the needs, goals, opportunities, and constraints of a number of programs in Costa Rica
and Belize, such as a forestry education project and a zoo outreach program. It provided a basis for making planning decisions
incorporating specific objectives, such as the reforestation of a region or a change in knowledge and attitudes in program
participants. Process evaluation provided a Costa Rican sustainable development program with feedback during its implementation
and enabled it to modify and improve its newsletter for local farmers and its ecology classes for school children. Product
evaluation assessed project accomplishments, such as the $700,000 raised by the Children's Rainforest group and the 20 miles
of riparian land under conservation management as part of the Belize Community Baboon Sanctuary project. Outcomes are compared
with the programs original monetary or land management objectives to determine the success of the programs and to provide
feedback for improvement. 相似文献
846.
M. D. Mattson P. J. Godfrey M. F. Walk P. A. Kerr O. T. Zajicek 《Journal of the American Water Resources Association》1992,28(6):1045-1056
ABSTRACT: We surveyed over 2000 lakes in the State of Massachusetts (1983–1984) to examine the spatial variations in their acid-base chemistry. Our survey differed from previous surveys by including small lakes and nonpristine urban lakes. For samples collected in October 1983 and 1984, the median acid neutralizing capacity (ANC) was 184 μeq L?1 and 5.9 percent were acidic (ANC≤O). Small lakes (<4 ha) were more likely to be acidic than large lakes. Generally, sulfate was the dominant acidifying agent, although organic anions were dominant in some of the lakes in the Cape Cod Region. The ionic composition of the lakes showed strong regional patterns which appear to be related to geology and human population density. An analysis of variance of ANC shows the six regional categories in the state explain 51 percent of the variance, while a combined general linear model of lake drainage type, color, elevation, size, silica, and hydrogen ion deposition could explain only 4.9 percent of the variation in ANC. Calcium rich, high ionic strength lakes were present in the marble bedrock in the west, and relatively dilute lakes dominated by sodium and chloride were found near the coast. Chloride concentrations were also related to population density, suggesting road salt as a likely contributing source. 相似文献
847.
Socioeconomic, demographic, and attitudinal factors likely to influence individual initiative to use control measures against
gypsy moth infestation in New Hampshire are examined. Data were acquired through a mail survey from 629 individuals in three
targeted towns: Bow, Conway, and Exeter. Using logit regression analysis, numerous variables are shown to be statistically
significant in influencing an individual's willingness to use control measures. The influencing factors include: the individual
knowing the difference between the gypsy moth caterpillar and the eastern tent caterpillar; the individual being a homeowner
rather than a renter; the number of acres of land accompanying the individual's dwelling; the number of trees on the individual's
property; the individual's gender; and the individual's level of income. Aesthetic damage and the nuisance caused by gypsy
moth infestation were the primary reasons for individuals to use control measures. The results from this study indicate that
the motivation behind an individual's initiative to use control measures is influenced by diverse and varying factors. The
models, methodology, and results as applied and presented here are exploratory in nature, yet could prove informative for
researchers seeking a greater understanding of the interaction between humans and insect pests. 相似文献
848.
The failure to anticipate the public's response to environmental problems can lead to expensive delays, bad public relations, and litigation, as well as environmental decisions that do not represent public values and preferences. This study examines the influence of conflict between management goals, perceived resource scarcity, and information bias on evaluations of the importance of management goals; the perception of conflicts among the goals; and the emotions evoked in an urban forest management problem. Environmental problem scenarios were systematically manipulated as to the level of conflict between development and natural preservation goals, the scarcity of urban nature, and the bias of the presented information. Evaluations of the importance of urban nature and economic development were susceptible to manipulations of scarcity. The importance of urban nature was also higher when information was biased toward pro-preservation issues. Negative emotions were associated with high conflict and scarcity and with the propreservation information bias. Both evaluations of goal importance and conflict among goals appeared to be based on an underlying economics-versus-amenity dimension. These results are similar to previous studies of environmental decision making with regard to nonurban environmental problems. This research offers a beginning in understanding and anticipating the way members of the public may respond to information about environmental problems. 相似文献
849.
Abstract: In developed countries dogs (Canis lupus familiaris) are permitted to accompany human visitors to many protected areas (e.g., >96% of protected lands in California, U.S.A.), and protected‐area management often focuses on regulating dogs due to concerns about predation, competition, or transmission of disease and conflicts with human visitors. In 2004 and 2005, we investigated whether carnivore species richness and abundance were associated with management of domestic dogs and recreational visitation in protected areas in northern California. We surveyed for mammalian carnivores and human visitors in 21 recreation areas in which dogs were allowed offleash or onleash or were excluded, and we compared our observations in the recreation areas with observations in seven reference sites that were not open to the public. Carnivore abundance and species richness did not differ among the three types of recreation areas, but native carnivore species richness was 1.7 times greater (p < 0.01) and the relative abundances of native coyotes (Canis latrans) and bobcats (Lynx rufus) were over four times greater (p < 0.01) in the reference sites. Abundances of bobcats and all carnivores declined as the number of visitors increased. The policy on domestic dogs did not appear to affect species richness and abundance of mammalian carnivores. But the number of dogs we observed was strongly associated with human visitation (R2= 0.54), so the key factors associated with recreational effects on carnivores appear to be the presence and number of human visitors to protected areas. 相似文献
850.