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91.
Conservation policy and practice is increasingly turning towards market-based interventions to reconcile the growing conflicts between environmental conservation and rural livelihood needs. This short introductory paper to the special issue on “market-oriented conservation governance” critically investigates the growing commitment to markets as a means of meeting conservation objectives and livelihood security. We distinguish market oriented conservation from neoliberal conservation and argue for a grounded, empirically rich investigation into the passive and active promotion of markets in conservation landscapes – analysis which pays attention to how and why certain markets are promoted by ENGOs, governments and private sector, as well as how rural people negotiate livelihoods and markets when adjusting to conservation pressures. Such an approach takes seriously how the particularities of place, from local harvests to trans-local trade, shape market-oriented conservation in practice and expose the messiness of such ventures. The range of papers in this special issue show how neither neoliberal nor market-based interventions in conservation are uniform in character, impact and outcome, and that while identifying the patterns and logic behind these processes remains crucial, the basis for understanding how markets inform conservation, must be done by drawing on empirical data that speaks clearly to how actors variously engage the logic of market-driven conservation in terms of their histories and contemporary realities. We argue that doing so makes it possible to understand not only what is ‘new’ about contemporary market-oriented conservation but also its continuities with earlier forms of command and control conservation.  相似文献   
92.
The third body perturbation of an orbiter of a planet or moon is considered. A very convenient form of the Lagrange equations is given allowing an easy derivation of the various terms of the expansion of the perturbed elements. A careful analysis of the order of magnitude of these terms indicates which ones are required for a consistent theory. It follows that in many practical cases the main term of the disturbing function has to be carried to the second order of the perturbation theory.Paper presented at the 1981 Oberwolfach Conference on Mathematical Methods in Celestial Mechanics.Dedicated to V. Szebehely on the occasion of his 60th birthday  相似文献   
93.
The extragalactic flux of protons is predicted to be suppressed above the famous Greisen–Zatsepin–Kuzmin cut-off at about EGZK  50 EeV due to the resonant photo-pion production with the cosmic microwave background. Current cosmic ray data do not give a conclusive confirmation of the GZK cut-off and the quest about the origin and the chemical composition of the highest energy cosmic rays is still open. Amongst other particles neutrinos are expected to add to the composition of the cosmic radiation at highest energies. We present an approach to simulate neutrino induced air showers by a full Monte Carlo simulation chain. Starting with neutrinos at the top of the atmosphere, the performed simulations take into account the details of the neutrino propagation inside the Earth and atmosphere as well as inside the surrounding mountains. The products of the interactions are input for air shower simulations. The mountains are modelled by means of a digital elevation map. To exemplify the potential and features of the developed tools we study the possibility to detect neutrino induced extensive air showers with the fluorescence detector set-up of the Pierre Auger Observatory. Both, down-going neutrinos and up-going neutrinos are simulated and their rates are determined. To evaluate the sensitivity, as a function of the incoming direction, the aperture, the acceptance and the total observable event rates are calculated for the Waxman–Bahcall (WB) bound.  相似文献   
94.
A statistical study using data from four geomagnetic recording stations with McIlwain parameters from L = 2.5 to 6.6, suggests that the general source location of Pc 1 micropulsations lies close to the plasmapause.For each station a contour plot of the number of Pc 1 events occurring at specific Kp, and LT intervals is constructed and a curve representing the plasmapause being overhead at this station is superimposed. The relative positions of the plasmapause curve and the contour maxima are taken to indicate the position of the Pc 1 source location.  相似文献   
95.
We describe a project to study the state of the ISM in ∼20 low redshift (z < 0.3) QSO host galaxies observed with the PMAS integral field spectrograph. We describe the development of the method to access the stellar and gas components of the spectrum without the strong nuclear emission, in order to access the host galaxy properties in the central region. It shows that integral field spectroscopy promises to be very efficient in studying the gas distribution and its velocity field, and also the spatially resolved stellar population in the host galaxies of luminous AGN. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
96.
The quantitative spectroscopy of stellar objects in complex environments is mainly limited by the ability of separating the object from the background. Standard slit spectroscopy, restricting the field of view to one dimension, is obviously not the proper technique in general. The emerging Integral Field (3D) technique with spatially resolved spectra of a two‐dimensional field of view provides a great potential for applying advanced subtraction methods. In this paper an image reconstruction algorithm to separate point sources and a smooth background is applied to 3D data. Several performance tests demonstrate the photometric quality of the method. The algorithm is applied to real 3D observations of a sample Planetary Nebula in M31, whose spectrum is contaminated by the bright and complex galaxy background. The ability of separating sources is also studied in a crowded field in M33. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
97.
98.
Arsenic Removal from Natural Groundwater Using Cupric Oxide   总被引:1,自引:0,他引:1  
Groundwater is a main source of drinking water for some rural areas. People in these rural areas are potentially at risk from elevated levels of arsenic (As) due to a lack of water treatment facilities. The objectives of this study were to (1) measure As concentrations in approximately 50 groundwater samples from rural domestic wells in the western United States, (2) explore the potential of cupric oxide (CuO) particles in removal of As from groundwater samples under natural conditions (i.e., without adding competing anions and adjusting the pH or oxidation state), and (3) determine the effects of As removal on the chemistry of groundwater samples. Forty‐six groundwater well samples from rural domestic areas were tested in this study. More than 50% of these samples exceeded the U.S. Environmental Protection Agency Maximum Contaminant Limit (US EPA MCL) of 10 µg/L for As. CuO particles effectively removed As from groundwater samples across a wide range of pH (7.11 and 8.95) and concentrations of competing anions including phosphate (<0.05 to 3.06 mg/L), silica (<1 to 54.5 mg/L), and sulfate (1.3 to 735 mg/L). Removal of As showed minor effects on the chemistry of groundwater samples, therefore most of the water quality parameters remained within the US EPA MCLs. Overall, results of this study could help develop a simple one‐step process to remove As from groundwater.  相似文献   
99.
Summary In the past, experimental investigations as well as theoretical considerations have shown that within fronts and inversions wind shear and vertical temperature gradient adjust in such a way that the Richardson number is at its critical value. Results from aircraft measurements now suggest that the shear within moving cold fronts, warm fronts and inversions shows different behaviour because of the different mechanisms controlling the Richardson numbers. This leads to higher Richardson numbers, and therefore to lower amounts of wind shear within moving cold fronts when compared to warm fronts and inversions.With 9 Figures  相似文献   
100.
Vu  Tam Bang  Noy  Ilan 《Natural Hazards》2014,75(2):111-126

We examine the effects of natural disasters on income and investment in China. Using macroeconomic province-level data and the provincial history of disaster exposure over the past two decades, we describe the relationship between disaster mortality and morbidity, disasters’ economic damages, government investment and regional economic activity, and infrastructure development. The Chinese government’s aggressive investment in post-disaster reconstruction is discussed, and the implications of this investment for post-disaster private sector economic activity are analyzed empirically. We further investigate the differential effects of natural disasters on economic activity in China’s diverse geographical regions.

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