BE/CNH: The Vulnerability and Adaptive Capacity of Coupled Human-Environment Systems in the Southern Yucatan Peninsular Region

土地变化和可持续性科学呼吁更多地关注人类与环境耦合系统在面对气候变化时，面对与人类需求增加相关的各种压力和扰动时的脆弱性和复原力。季节性热带森林生物群落需要特别注意，因为其中发生了大量的森林砍伐。自1997年以来，一个大型的跨学科项目一直在开发数据和分析，以了解森林砍伐的人类和生物物理动态，并对包括卡拉克穆尔生物圈保护区在内的尤卡坦南部的土地变化进行建模和规划。所获得的了解正在用于深入了解该区域土地利用和土地覆盖相结合的脆弱性和复原力，最终建立全面的脆弱性研究。该项目旨在确定与陆地系统持续的人类干扰和日益干旱（气候变化）有关的一些关键因素。它将完成现有的极其详细的森林覆盖分类及其准确性评估工作，并将通过ASTER图像使这项工作在2004年继续进行。该项目将建立一个AVHRR档案，最终解决以下问题：在现存的成熟森林中，标准化植被指数（NDVI）的测量值是否下降了？这是否与干旱加剧有关？这项研究还将利用现有数据和少量新数据来比较成熟森林和演替森林之间的凋落物，并检查土地历史对生物量积累的影响。该地区的碳储量估计将利用现有树木的测量数据以及凋落物和土壤的碳数据生成。将完成若干生物多样性数据集（样带捕获），以解决与森林砍伐引起的生境变化有关的生物多样性丧失问题。最后，将完成一项关于农民对最近的飓风伊西多尔的反应的调查，以确定不同家庭对飓风干扰的反应有多大差异。本研究建立在南尤卡坦半岛地区（SYPR）项目的基础上，该项目对任何地方进行的土地变化进行了最全面的评估之一，将生物物理和人类子系统动力学联系到几种不同类型的模型中，以解释和预测土地变化。从这个意义上说，它通过将自然科学、社会科学和空间科学联系起来，为新兴的土地变化科学提供了方法和分析方面的进步。土地变化科学现在转向系统对扰动和压力的反应问题，比如气候变化。SYPR项目也有能力在这方面发挥领导作用。这项研究将开始将项目过渡到美洲最重要的季节性热带森林之一的土地系统的脆弱性、复原力和可持续性问题。它开始提供以下问题的答案：森林类型和土地利用将如何应对一个更被占用、更频繁使用（砍伐和焚烧）、易受气候变化影响的景观？这些问题的答案对许多把这个地区称为家园的人以及位于该地区中心和中美洲生物走廊枢纽的卡拉克穆尔生物圈保护区都很重要。研究成果也将对在世界许多其他地区工作的学者和实践者具有更普遍的效用。

Land change and sustainability science calls for increased attention to the vulnerability and resilience of coupled human-environment systems to various stresses and perturbations tied to increased human demands in the face of climate change. Seasonal tropical forest biomes require special attention because of the amount of deforestation taking place in them. Since 1997, a large, interdisciplinary project has been developing data and analysis to understand the human and biophysical dynamics of deforestation, and to model and project land changes in the southern Yucatan, which includes the Calakmul Biosphere Reserve. The understanding gained is being used to develop insights about the vulnerability and resilience of coupled land uses and land covers in the region, ultimately building towards a full-blown vulnerability study. The project seeks to identify some of the critical factors linked to sustained human disturbance and increasing aridity (climate change) on the land systems. It will complete extant work on an extremely detailed forest-land cover classification and its accuracy assessment, and it will bring help make that work current into 2004, via ASTER imagery. The project will establish an AVHRR archive that will ultimately address the question: Have Normalized Difference Vegetation Index (NDVI) measurements decreased among the extant mature forests, and is this linked to increased aridity? The study will also use existing data and modest levels of new data to compare the litter between mature forests and successional forest and examine the impact of land history on biomass accumulation. A carbon stock estimate for the region will be generated using extant tree measurements as well as litter and soil carbon data. Several biodiversity data sets (transect captures) will be completed in order to address the question of biodiversity loss linked to habitat change from deforestation. Finally, a survey of farmer's responses to the recent hurricane Isidore will be completed to determine how differently endowed households respond to hurricane disturbances.The Southern Yucatan Peninsular Region (SYPR) project on which this study builds has laid out one of the most comprehensive assessments of land change undertaken anywhere, linking biophysical and human subsystem dynamics into several different kinds of models that explain and project land change. In this sense, it provides methodological and analytical advances for emerging land-change science by linking the natural, social, and spatial sciences. Land-change science now moves toward questions of system response to perturbations and stresses, such as climate change. The SYPR project has the capacity to take a leadership role in this effort as well. This research will begin the transition of the project to questions of vulnerability, resilience, and sustainability of land systems in one of the most important seasonal tropical forests remaining in the Americas. It begins to provide the answers to the question: How will forest types and land-uses respond to a more occupied, frequently used (cut and burned) landscape that is subject to climate change? The answers are important for the many people who call the region home as well as to the Calakmul Biosphere Reserve situated in the center of the region and pivotal the Mesoamerican Biological Corridor. Research results will have more general utility for scholars and practitioners working in many other parts of the world, too.