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771.
In recent years, as part of its neoliberal development paradigm, the Government of the Philippines has engaged in efforts to encourage extraction of the nation's mineral resources. The Philippines is also a country where decentralization has devolved substantial powers to local governments. Concern over potentially adverse environmental effects has led to opposition to mining by some local governments in the Philippines. This opposition has led to the withholding of consent to mining projects by local governments and, in some cases, the implementation of moratoriums banning mining. Central to this opposition have been the activities of civil society groups, and their collaboration with local governments. This collaboration has involved the drafting of legislation prohibiting mining and support of candidates for office who are opposed to mining. Collectively, Filipino local governments and civil society groups are examples of the concept of governance, a dispersed process wherein society manages itself for the betterment of all its members. For mining companies seeking to implement projects, it is no longer sufficient to have the consent of the national Government — that of local governance forces must also be considered. 相似文献
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Daniel S. Papp 《Resources Policy》1979,5(1):51-60
The tenth Soviet five year plan projected increased extraction of mineral resources and improved utilization of those resources. Through 1976 and 1977, actual production closely parallelled planned production in most resources. Even so, 1978 was a critical year for Soviet resources production, and may determine whether the goals of the tenth plan are achieved. Other areas of Soviet resource policy which are discussed include the drive to accelerate Siberian and far eastern development, the effort to improve capital and manpower efficiency, the attempt to improve resource use and reduce non-essential consumption, and the effort to import advanced extractive technology and capital. The article concludes with the observation that with the difficulties facing the Soviet extractive industries, the tenth plan may be the last which projects and strives for a rapid expansion of the Soviet resource base. 相似文献
775.
Daniel Kamykowski 《Ecological modelling》1981,12(4):253-265
Temperature data obtained from NUC Tower, San Diego, California during May–June 1968 provide input to a three-wave period version of MOVER, a computer model that simulates organism diurnal vertical migration through an internal wave field. The locally characteristic wave periods are 21.50 h, 12.50 h and 0.42 h. The phase of the modeled interval wave spectrum matches the field observations for a 10-day period preceding and including a red tide. MOVER's output shows a rapid aggregation of representative phytoplankton under all modeled conditions. The aggregation or red tide occurs at the geographic location of NUC Tower under certain organism behavioral regimes. Whether these conditions actually occurred at NUC Tower in May 1968 is not certain from the available data. 相似文献
776.
Art Daniel Zhanhe Wu Bruce Bennetts Howard Slater Robert Osborn Julianne Jackson Vladimir Pupko John Nelson Geoff Watson Claire Cooke-Yarborough Christine Loo 《黑龙江环境通报》2001,21(12):1034-1048
The parental origin of triploidy in 19 cases was examined by inheritance of DNA microsatellites and by methylation patterns of SNRPN or PW71 (where parents' blood was unavailable). The fetal and placental morphology on these cases was reviewed. The phenotype of the fetuses with non-mosaic triploidy was assessed in relation to the two types described by McFadden and Kalousek. Of the diandric fetuses three of the six showed mild-to-moderate symmetrical growth retardation and the other three had growth characteristics in accordance with their gestational ages. This study would suggest the fetal triploid ‘Type 1’ definition be modified to ‘well grown to moderate symmetrical IUGR’ to allow for such variation. In the digynic fetuses (McFadden/Kalousek Type 2) there were poor growth characteristics with IUGR being more severe and asymmetrical. The diandric fetuses were as common as digynic fetuses in this series. The ratio of diandric to digynic specimens was 11:8 but if only fetal specimens (not embryos or mosaic children) were included the ratio was 6:5. Many diandric conceptions end as partial moles but later in gestation diandric fetuses may be well grown. It is proposed that there may be a survival barrier for diandric fetuses early in gestation (possibly based on the proportion of vascularised placental villi), although once this is passed the diandric fetuses are comparatively more viable and better grown than digynic fetuses. In the XXY triploid fetuses, 5/6 had hypoplastic or ambiguous external genitalia (two were recorded as of female phenotype) as has been reported previously. In these, the gonadal histology was testicular in all the diandrics but in the single digynic XXY case, sex reversal was complete with normal uterus and Fallopian tubes and the gonads were histologically ovaries. Two triploid/diploid mosaics were proven to be due to digyny. The probable cause is delayed incorporation of the second polar body into a blastomere and there was evidence of identical alleles from the same sperm being present in both diploid and triploid cells. In one of these triploid/diploid mosaics in which there was a termination of pregnancy (TOP) after prenatal karyotyping the diploid cell line had trisomy 16 which was not evident in the triploid line. This trisomy was probably of post-zygotic origin and we suggest the fetus was rescued by the prominence of the triploid line. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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778.
Seventeen different wastewater sludges were characterized using both chemical and organic matter fractionation methods (water extraction, Van Soest method, and acid hydrolysis) and 6-mo incubation studies to assess their decomposition in soil. Simple correlation and multiple factor analysis (MFA) were then performed to establish relationships between composition and C and N mineralization of sludges. Carbon and N concentrations covered a wide range of values, but organic carbon (C(o)) to organic nitrogen (N(o)) ratios were relatively low (from 5 to 19). Carbon and N were mainly distributed in the most soluble fractions of the Van Soest method and in the water-insoluble fraction at 100 degrees C. Carbon mineralization varied from 180 to 661 g C kg(-1) organic C added during the 168-d incubation. The addition of sludges led to different inorganic N dynamics: from -3.3 to +120.0 g N kg(-1) sludge organic C mineralized after the 168-d incubation. Fractionation studies showed that the most discriminating method was acid hydrolysis. Carbon mineralization was linked with the proportion of sludge N and C present in the lignin-like fraction (r = -0.68 and -0.65, respectively). Significant relationships were established between N mineralization and N(o) to C(o) ratio (0.88 < r < 0.95) and the C(o) to N(o) ratio of sludges, the C to N ratio of the soluble fraction obtained by the Van Soest method, the water-soluble fraction at 100 degrees C, and the C and N present in the acid-hydrolyzable fraction. Finally, multiple factor analysis also enabled establishing a sludge typology using five clusters based on composition and mineralization characteristics. 相似文献
779.
DeLaune PB Moore PA Carman DK Sharpley AN Haggard BE Daniel TC 《Journal of environmental quality》2004,33(6):2192-2200
A phosphorus (P) index for pastures was developed to write nutrient management plans that determine how much P can be applied to a given field. The objectives of this study were to (i) evaluate and compare the P index for pastures, particularly the P source component, and an environmental threshold soil test P level by conducting rainfall simulations on contrasting soils under various management scenarios; and (ii) evaluate the P index for pastures on field-scale watersheds. Poultry litter was applied to 12 small plots on each of six farms based on either an environmental threshold soil test P level or on the P index for pastures, and P runoff was evaluated using rainfall simulators. The P index was also evaluated from two small (0.405 ha) watersheds that had been fertilized annually with poultry litter since 1995. Results from the small plot study showed that soil test P alone was a poor predictor of P concentrations in runoff water following poultry litter applications. The relationship between P in runoff and the amount of soluble P applied was highly significant. Furthermore, P concentrations in runoff from plots with and without litter applications were significantly correlated to P index values. Studies on pastures receiving natural rainfall and annual poultry litter applications indicated that the P index for pastures predicted P loss accurately without calibration (y = 1.16x - 0.23, r(2) = 0.83). These data indicate that the P index for pastures can accurately assess the risk of P loss from fields receiving poultry litter applications in Arkansas and provide a more realistic risk assessment than threshold soil test P levels. 相似文献
780.
Development of a phosphorus index for pastures fertilized with poultry litter--factors affecting phosphorus runoff 总被引:1,自引:0,他引:1
DeLaune PB Moore PA Carman DK Sharpley AN Haggard BE Daniel TC 《Journal of environmental quality》2004,33(6):2183-2191
Currently, several state and federal agencies are proposing upper limits on soil test phosphorus (P), above which animal manures cannot be applied, based on the assumption that high P concentrations in runoff are due to high soil test P. Recent studies show that other factors are more indicative of P concentrations in runoff from areas where manure is being applied. The original P index was developed as an alternative P management tool incorporating factors affecting both the source and transport of P. The objective of this research was to evaluate the effects of multiple variables on P concentrations in runoff water and to construct a P source component of a P index for pastures that incorporates these effects. The evaluated variables were: (i) soil test P, (ii) soluble P in poultry litter, (iii) P in poultry diets, (iv) fertilizer type, and (v) poultry litter application rate. Field studies with simulated rainfall showed that P runoff was affected by the amount of soluble P applied in the fertilizer source. Before manure applications, soil test P was directly related to soluble P concentrations in runoff water. However, soil test P had little effect on P runoff after animal manure was applied. Unlike most other P indices, weighting factors of the P source components in the P index for pastures are based on results from runoff studies conducted under various management scenarios. As a result, weighting factors for the P source potential variables are well justified. A modification of the P index using scientific data should strengthen the ability of the P index concept to evaluate locations and management alternatives for P losses. 相似文献