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281.
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283.
Samuel A. Bamberg Herbert N. Friesen 《Journal of the American Water Resources Association》1972,8(6):1108-1119
A technique is presented for developing an isohyet map for the Hualapai Valley, a closed hydrologic basin of about 315 square miles in the northwestern Great Basin in Nevada. In this basin there is practically no climatic data, and in the northwest Great Basin there are too few stations for determination of rainfall on a detailed basis. Using a vegetational typing to represent a range in elevation and precipitation, an initial mean annual rainfall is determined for selected points on a grid pattern. This rainfall is then modified by using topographic parameters of slope, orientation, exposure, and rainfall shadow effect. The resulting point determinations of mean annual rainfall are then smoothed using a trend surface analysis, and an isohyetal map is drawn from the smoothed points. The technique provides an estimated accuracy of one inch of mean annual precipitation and one mile of resolution on isohyets. 相似文献
284.
Alfredo Mahar Lagmay Jerico Mendoz Fatima Cipriano Patricia Anne Delmendo Micah Nieves Lacsaman Marc Anthony Moises Nicanor Pellejera III Kenneth Ni?o Punay Glenn Sabio Laurize Santos Jonathan Serrano Herbert James Taniz Neil Eneri Tingin 《环境科学学报(英文版)》2017,29(9):39-47
Urban floods from thunderstorms cause severe problems in Metro Manila due to road traffic. Using Light Detection and Ranging (LiDAR)-derived topography, flood simulations and anecdotal reports, the root of surface flood problems in Metro Manila is identified. Majority of flood-prone areas are along the intersection of creeks and streets located in topographic lows. When creeks overflow or when rapidly accumulated street flood does not drain fast enough to the nearest stream channel, the intersecting road also gets flooded. Possible solutions include the elevation of roads or construction of well-designed drainage structures leading to the creeks. Proposed solutions to the flood problem of Metro Manila may avoid paralyzing traffic problems due to short-lived rain events, which according to Japan International Cooperation Agency (JICA) cost the Philippine economy 2.4 billion pesos/day. 相似文献
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286.
Bhatnagar YV Wangchuk R Prins HH Van Wieren SE Mishra C 《Environmental management》2006,38(6):934-941
An emerging conflict with Trans-Himalayan pastoral communities in Ladakh’s Changthang Plateau threatens the conservation prospects
of the kiang (Equus kiang) in India. It is locally believed that Changthang’s rangelands are overstocked with kiang, resulting in forage competition
with livestock. Here, we provide a review and preliminary data on the causes of this conflict. Erosion of people’s tolerance
of the kiang can be attributed to factors such as the loss of traditional pastures during an Indo-Chinese war fought in 1962,
immigration of refugees from Tibet, doubling of the livestock population in about 20 years, and increasing commercialization
of cashmere (pashmina) production. The perception of kiang overstocking appears misplaced, because our range-wide density estimate of 0.24 kiang
km−2 (± 0.44, 95% CL) is comparable to kiang densities reported from Tibet. A catastrophic decline during the war and subsequent
recovery of the kiang population apparently led to the overstocking perception in Ladakh. In the Hanle Valley, an important
area for the kiang, its density was higher (0.56 km−2) although even here, we estimated the total forage consumed by kiang to be only 3–4% compared to 96–97% consumed by the large
livestock population (78 km−2). Our analysis nevertheless suggests that at a localized scale, some herders do face serious forage competition from kiang
in key areas such as moist sedge meadows, and thus management strategies also need to be devised at this scale. In-depth socioeconomic
surveys are needed to understand the full extent of the conflicts, and herder-centered participatory resolution needs to be
facilitated to ensure that a sustainable solution for livelihoods and kiang conservation is achieved. 相似文献