铁木森林国家保护区生物调查 一般的植被 大约一半的纪念碑的植被(35,000公顷, 86,500英亩, 45%) is 亚利桑那州高地 subdivision (AZU) of the Sonoran Desert (Brown 1982). We classified most of the rest as 科罗拉多河下游河谷 subdivision (LCV), 尽管一些植物学家将其归类为AZU. There is an anomalous vegetation type near the summit of 银钟 Peak in which jojoba is the dominant plant and forms nearly continuous stands. 它也发生在图森山脉，在那里Rondeau等人. (1996)似乎把它包括在亚利桑那高地. 这种植物的面貌是 茂密的树丛 2022世界杯下注暂时把它归类为. 荷荷巴丛林占地648公顷(1600英亩).纪念碑面积的8%.
铁木森林 National Monument spans the transition between 亚利桑那州高地 and 科罗拉多河下游河谷. 亚利桑那州高地 is characterized by saguaros and legume trees growing on mountain slopes and bajadas (Shreve 1964). Intervening valleys are relatively narrow and also densely-vegetated for a desert, but ironwood trees and saguaros are uncommon because of killing winter frosts and excessively wet soils in rainy years. 亚利桑那州高地在罗斯克鲁奇地区很发达, 银钟, 衣衫褴褛的顶部, 和沃特曼山脉(见左栏的图库链接). Vegetation density and floral diversity are lower in the West 银钟 Mountains and still lower in the Sawtooth Mountains. 一些植被地图将锯齿树放在LCV中, but we labeled them marginal AZU because of the sparse cover of trees and saguaros on the slopes.
The hotter, more arid LCV is characterized by low, rocky mountain ranges separated by broad valleys. The slopes of the ranges are usually devoid of both trees and saguaros because of the extreme aridity. Saguaros and ironwood trees grow on the lower bajadas and valley floors that, 因为海拔较低, 比阿联的天气暖和吗. An additional reason is that the fine-grained soils hold more moisture than the rocky slopes. The trees in this hyperarid habitat are mostly restricted to drainages that concentrate runoff from watersheds. Avra山谷是LCV的最东端延伸，是非典型的. The valley floor is higher in elevation and is therefore both wetter and colder than other LCV valleys. Ironwood trees and saguaros are uncommon here; the washes are dominated by velvet mesquites and often contain blue palo verde trees. The Aguirre and Tat Momoli valleys on the west side of IFNM and the Santa Cruz Flats on the northern boundary are more typical LCV. 树, 包括铁木, are concentrated in washes and saguaros are sparsely distributed on the intervening flats. 详细的植被
重要的植被类型. 全尺寸图像包含图例. |
几个 优质或稀有的植被类型 都被详细地绘制出来了. See links to image galleries at left and in thumbnails with the text below.
1. 稠密的亚利桑那高地: The heart of IFNM has large areas of well-developed 亚利桑那州高地 that includes dense groves of ironwood trees. These areas also usually support above-average saguaro and foothill palo verde densities. Additional dense saguaro stands occur in otherwise ordinary AZU vegetation.
2. 科罗拉多河谷下游有大片的铁树林: The largest ironwood trees occur in drainages in the lower elevation valleys. Some are in braided washes or sheet-flooded areas that do not appear to be channelized on the ground.
3. 荷荷巴油茂密的树丛: Whether this is truly 茂密的树丛 or an odd association within 亚利桑那州高地, 它是IFNM中罕见的植被类型.
 4. 干旱林地:沙漠冲刷 are identical to wetter riparian areas as to ecological functions; the only difference is that washes only occasionally have surface water. 就像河流, 沙漠冲刷着收获的水, 营养物质, and seeds from watersheds and support greater densities of life than adjacent land. 较大的河流支撑着浓密的树带. LCV和AZU洗涤分别映射(项目2和5分别). In 亚利桑那州高地 the trees are mostly ironwood and blue palo verde with some mesquite. 少数AZU洗濯区有大量的大型铁木树. In 科罗拉多河下游河谷 Sonoran Desert the washes are more variable. 在有些地方，几乎所有的树都是菊科植物. Others are dominated by either blue palo verde or ironwood, or a mixture of all three trees. Desert willow (Chilopsis linearis) is also often present in LCV washes, but this species is conspicuously absent from 铁木森林 National Monument.
Washes are dispersal corridors for animals and plants (including exotic species). 陆龟大多生活在基岩高地, 但延伸到bajadas甚至沿着岩石冲刷的沙漠地面, especially those with caliche banks that readily form suitable shelters.
沙漠冲刷占据了沙漠栖息地的一小部分, and both plants and wildlife are concentrated along these narrow ribbons. 越干燥的地区，相对浓度越大. In the hyperarid desert of southeastern California as much as 90% of the biomass is restricted to washes No section of IFNM is that dry, 但无论如何，水塘都是极有价值的栖息地.
因为这里有更丰富的植物和野生动物, 欢迎遮阳的可用性, and the fact that they often provide convenient corridors for vehicle travel, 人们被洗涤所吸引. They are highly vulnerable to human disturbance despite the fact that they are regularly disturbed by flash floods. 车辆, 马, and people on foot trample plants that establish in wash channels between the infrequent scouring floods. Animals are also disturbed; nesting birds are probably the most vulnerable to reproductive failure from repeated disturbance.
5. 仙人掌和其他仙人掌的“森林”有几个地区有密集的菊科植物. The largest is in the Pan Quemado Mountains, where an intermittent band of chainfruit cholla (Cylindropuntia fulgida)几乎包围了整个山脉. Other thick cactus patches are documented in the gallery, especially the saguaro forests. 
6. 仙人掌沙丘 west of the Sawtooth Mountains: This small area is unique within 铁木森林 National Monument and rare elsewhere. 它大部分是平坦的, 宽松的, pinkish sand densely vegetated with several opuntioid and other cactus species. 仙人掌是与山麓植物共占主导地位的生命形式. Where a stabilized dune piles up against Wildcat Peak big galleta grass (Pleuraphis rigida)也很常见。. 据2022世界杯下注所知，唯一类似的地方是豪斯附近的仙人掌平原, AZ; that area has a much lower plant and cactus density and diversity.
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