Treesearch

Tropical forest disturbance (such as selective logging and fire) along with deforestation have significant contributions to the carbon source due to land-use change and anthropogenic CO2 emissions, and thus envisioned by United Nation's REDD+ programme. In previous work, spaceborne single-pass InSAR phase-center height has been shown to have the capability of accurately monitoring the subtle height change due to forest growth and degradation (with meter or even sub-meter level RMSE about the regression curve fit to time). In this paper, a new approach using spaceborne SAR interferometry...

Foresters have long applied the principle of matching site with trees in forestry. Finding suitable sites for a tree species, or finding suitable tree species for a given site, have typically been achieved through comprehensive understanding of plant–soil relationships by observations or correlation analyses. A recent study offered an eye–opening approach of using site calcium supply potentials to evaluate the site quality for tree plantations. When tree growth demand for calcium equals to site calcium supply, the site is then suitable for the tree species. Deviation from this calcium...

The Regional Assessment Report on Biodiversity and Ecosystem Services for the Americas produced by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) provides a critical analysis of the state of knowledge regarding the importance, status, and trends of biodiversity and nature’s contributions to people. The assessment analyses the direct and underlying causes for the observed changes in biodiversity and in nature’s contributions to people, and the impact that these changes have on the quality of life of people. The assessment, finally, identifies a...

Clouds and cloud shadows block land surface information in optical satellite images. Accurate detection of clouds and cloud shadows can help exclude these contaminated pixels in further applications. Existing cloud screening methods are challenged by cloudy regions where most of satellite images are contaminated by clouds. To solve this problem for landscapes where the typical frequency of cloud-free observations of a pixel is too small to use existing methods to mask clouds and shadows, this study presents a new Automatic Time-Series Analysis (ATSA) method to screen clouds and cloud...

Recent droughts in Puerto Rico and throughout the Caribbean have emphasized the region's agricultural vulnerability to this hazard and the increasing need for adaptation mechanisms to support sustainable production. In this study, we assessed the geographic extent of agricultural conservation practices incentivized by US Department of Agriculture Natural Resources Conservation Service (NRCS) and evaluated their large-scale contribution to drought adaptability. We identified concentrations of drought-related practices (e.g. cover crops, ponds) applied between 2000 and 2016. Using information...

We studied the response to hurricanes of 2 Pinus caribaea Morelet var. hondurensis Barr. & Golf. (Honduran Pine) plantations and paired secondary forests over a period of 32 years (1982 to 2014). Plantations differed in age (38 and 53.5 years old), as did the paired secondary forests. The study included the passage of 2 hurricanes (1989 and 1998). The hurricanes altered forest structure by lowering the basal area and tree density, accelerated tree mortality to over 5% per year and ingrowth rate to over 200 stems/ha at the Cubuy plantation, caused variability and reduction in individual...

Tropical tree species have evolved under very narrow temperature ranges compared to temperate forest species. Studies suggest that tropical trees may be more vulnerable to continued warming compared to temperate species, as tropical trees have shown declines in growth and photosynthesis at elevated temperatures. However, regional and global vegetation models lack the data needed to accurately represent such physiological responses to increased temperatures, especially for tropical forests. To address this need, we compared instantaneous photosynthetic temperature responses of mature canopy...

NASA's Black Marble nighttime lights product suite (VNP46) is available at 500m resolution since January 2012 with data from the Visible Infrared Imaging Radiometer Suite (VIIRS) Day/Night Band (DNB) onboard the Suomi National Polar-orbiting Platform (SNPP). The retrieval algorithm, developed and implemented for routine global processing at NASA's Land Science Investigator-led Processing System (SIPS), utilizes all high-quality, cloud-free, atmospheric-, terrain-, vegetation-, snow-, lunar-, and stray light-corrected radiances to estimate daily nighttime lights (NTL) and other intrinsic...