CRB: Testing Enrichment Planting in Fragmented Tropical Landscapes

拟议的项目将通过实验测试蝙蝠和鸟类传播种子的效果，并与风传播种子的效果进行比较，以克服热带树木在墨西哥韦拉克鲁斯严重改变的农作物、牧场和森林残留物的农业马赛克中的传播限制。最近制定的选择在牧场环境中存活良好的后期演替树种的标准将被用于在距Los Tuxtlas森林(644公顷的生物保护区和3400公顷的毗连林)100至1000米处种植8个半公顷的后期演替树种(9种)和先锋树种(3种)，以及8个类似的后期演替树种(9种)和先锋动物散布树种。初始阶段将测试对保护区先锋和后期演替物种种子雨和幼苗建立的预测，作为与连续森林或较小残留物的距离、成熟植被的年龄以及种植的树木成熟后的扩散综合症(动物或风扩散)的函数。目标不是恢复热带森林生态系统；在可预见的未来，种植的混交林和现有残留物周围的土地仍将是密集管理的农业景观。最终目标是测试使用空中种子传播剂增加和保持种植林和残留物之间的连通性的方法，并在这样做的过程中找到在永久农业花叶中增加和保持动植物多样性的方法。这是一项具有更广泛影响的雄心勃勃的科学建议，通过培训和鼓励大量充满活力的本科生和研究生群体，可能会使直接的科学目标相形见绌。目标将是鼓励和培训学生设计方法来管理整个新热带地区的农业马赛克，应用和改进方法，在热带农业经济的现实中使用实验性恢复来保护和促进生物多样性。

The proposed project will experimentally test the efficacy of seed dispersal by bats and birds as compared with seed dispersal by wind in overcoming dispersal limitation of tropical trees in an intensively altered agricultural mosaic of crops, pastures, and forest remnants in Veracruz, Mexico. Recently-developed criteria for selecting late-successional species that survive well in pasture environments will be used to plant 8 half hectare (ha) grids of late-successional wind-dispersed (9 species) and pioneer (3 species) trees and 8 similar grids of late-successional (9 species) and pioneer (3 species) animal-dispersed trees at distances from the Los Tuxtlas forest (Biological Reserve of 644 ha and contiguous forest of 3400 ha) from 100 to 1000 m into the agricultural mosaic. The initial phase will test predictions of seed rain and seedling establishment of pioneer and late-successional species from the reserve as a function of distance from the continuous forest or smaller remnants, age of maturing vegetation, and dispersal syndrome (animal- or wind-dispersed) of planted trees as they mature. The objective is not to restore a tropical forest ecosystem; the land surrounding planted mixed stands and existing remnants will remain intensively managed agricultural landscapes for the foreseeable future. The ultimate objective is to test means of increasing and maintaining connectance among planted stands and remnants using airborne agents of seed dispersal, and in so doing find means of increasing and maintaining faunal and floral diversity within a permanent agricultural mosaic. This is an ambitious scientific proposal with wider implications that may dwarf direct scientific objectives through the training, encouragement of a large and energized undergraduate and graduate student body. The goal will be to encourage and train students to devise ways of managing agricultural mosaics throughout the Neotropics, applying and refining methods that preserve and promote biodiversity using experimental restoration within the reality of tropical agrarian economies.