Factors Influencing Vegetation Trends in Dryland Zones

土地退化是一个重大威胁，可能减少农业生产，给人类造成极大痛苦。干旱地区尤其如此，气候、土壤和人类活动相互作用，造成荒漠化，干旱和半干旱地区生态系统服务减少或丧失，对人、动物和植物产生不利影响。几乎整个美国西半部都被认为是旱地，我国1930年代的沙尘暴经常被引用为典型的大规模荒漠化例子。严重的干旱，不适当的农业实践和脆弱的土壤造成了广泛的沙尘暴和巨大的作物和牲畜损失在南部大平原。半干旱非洲和亚洲部分地区的严重干旱和随之而来的饥荒也与荒漠化有关。因为它影响到地球仪人口的很大一部分，所以1994年签署了《联合国防治荒漠化公约》。尽管有这些历史事件和全球关注，荒漠化仍然是一个人们知之甚少、往往有争议的环境过程。关于地方、区域和全球范围内艾滋病毒/艾滋病的发生率、范围和严重程度的基本问题经常在科学研究中得到审查，但很少得到明确的回答。其中最大的问题之一是，荒漠化一旦开始，是否能够扭转，如果能够，如何扭转？ 这项研究使用了一个测试案例，即1970年代和1980年代的干旱引发了广泛的荒漠化，最近的卫星图像显示植被增加的大规模集群，或可能反过来荒漠化。位于查佩尔山的北卡罗来纳州大学的Colin West博士和Aaron Moody博士将探讨是什么因素推动旱地地区绿化的植被趋势。这项研究将检验当地土地利用做法驱动区域植被趋势的假设。这项研究将在布基纳法索北方进行，其中一名研究人员自2002年以来一直在那里进行长期的人类学工作。在国家科学基金会先前的支持下，研究小组收集了一系列卫星图像，显示了绿化（荒漠化可能逆转）和布朗宁（荒漠化可能加速）的不同地区。以这些结果为指导，他们试图通过询问当地农民和牧民对环境变化的看法来确定这些模式。这位人类学家、他的研究生和当地合作者将利用高分辨率卫星图像在被认为是绿化、布朗宁和混合的地区举办研讨会。其他学生将使用遥感程序处理和分析这些图像，以测量这三个区域的植被数量。该研究预测，绿色区将有更多的树木比棕色区和混合区将是中间。研讨会将当地的资源使用者也将寻求他们的观点，如何气候，土地使用的做法，和土壤相互作用，以产生这些pattern.This奖项反映了NSF的法定使命，并已被认为是值得通过评估使用基金会的知识价值和更广泛的影响审查标准的支持。

Land degradation is a significant threat that can reduce agricultural production and cause extreme human suffering. This is particularly true in drylands where climate, soils, and human activities interact to produce desertification, the reduction or loss of ecosystem services in arid and semi-arid regions that negatively affect people, animals, and plants. Nearly the entire western half of the United States is considered a dryland and our country's Dust Bowl of the 1930s is often cited a classic large-scale example of desertification. Severe droughts, inappropriate agricultural practices, and fragile soils caused widespread dust storms and enormous crop and cattle losses in the southern Great Plains. Severe droughts and attending famines in semi-arid Africa and parts of Asia have also been linked to desertification. Because it affects a huge portion of the globe's population, there is a United Nations Convention to Combat Desertification (UNCCD), which was signed in 1994. Despite these historical events and global concern, desertification remains a poorly understood and often controversial environmental process. Basic questions concerning its rate, extent and severity at local, regional and global scales are frequently examined in scientific studies but rarely definitively answered. One of the largest of these questions concerns whether or not desertification, once started, can be reversed and, if so, how? This study uses a test case where droughts in the 1970s and 1980s initiated widespread desertification and where recent satellite images suggest large-scale clusters of increased vegetation, or potentially desertification in reverse. Dr. Colin West and Dr. Aaron Moody of the University of North Carolina at Chapel Hill will explore what factors drive vegetation trends in the greening of dryland zones. This study would test the hypothesis that local land-use practices drive regional vegetation trends. The research would take place in northern Burkina Faso, where one of the researchers has conducted long-term anthropological work since 2002. With previous support from the National Science Foundation, the research team has assembled a time series of satellite images that show distinct areas of both greening (where desertification may be in reverse) and browning (where desertification may be accelerating). Using these results as a guide, they seek to ground-truth these patterns by asking local farmers and herders about their perceptions of environmental change. The anthropologist, his graduate students, and local collaborators will conduct workshops using high-resolution satellite images in areas considered greening, browning and mixed. Using remote sensing procedures, other students will process and analyze these images to measure the amount of vegetation in the three zones. The study predicts that green zones will have more trees than brown zones and that the mixed zone will be intermediate. Workshops will local resource users will also seek their perspectives on how climate, land-use practices, and soils interact to produce these patterns.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.