Post Doctorate RA - Soil Microbiome Bioinformatics in RICHLAND, Washington
Post Doctorate RA - Soil Microbiome Bioinformatics in RICHLAND, Washington
Start Date: As soon as possible
Closing Date for Applications: midnight on Friday 16th September 2016
The Mezquital valley, 80 km north of the metropolitan area of Mexico City (MAMC), is an example of a low cost Soil-Aquifer-Treatment system, in which untreated sewage and surface runoff collected within the closed basin of Mexico, are used to irrigate mainly fodder crops and maize. The valley is at 2100 m asl, and has a temperate semi-arid climate. Natural vegetation corresponds to xerophytic shrublands, but irrigation has changed the natural hydrologic environment and the land cover. Today more than 90,000 ha are cultivated mainly with lucerne and maize cropped in rotation. The soil moisture regime has changed from ustic to udic, and there is an artificial groundwater recharge of 6 m3/s of the semi-confined upper aquifer. Supply water for more than 500,000 inhabitants of the valley is provided by this semi-confined aquifer.
Our working group manages a critical zone observatory in this area since 1990. The objective is to evaluate the impact of long-term irrigation on the soil, crop, groundwater and air quality in the region. We also collaborate in assessing the impact on human health. We do this following two main strategies:
We have repeatedly sampled fields irrigated for different lengths of time with untreated wastewater in 1990 and 2009, respectively. Fields are distributed among the dominant soil types, namely Leptosols, Phaeozems and Vertisols (Calciustolls and Pellusterts). In these fields we have sampled soils (by genetic horizon and also composite samples from the upper 30 cm) and crops, and have analyzed them for nutrients and pollutants as heavy metals, pharmaceuticals, detergents and salts. We have also studied the microbial communities and their activity.
Since 2008 we are monitoring critical zone processes during single irrigation events to follow groundwater recharge, nutrient and pollutant leaching as well as greenhouse gas emissions. This has been done along a transect crossing the extended piedmont of the valley. We have installed deep piezometers (30 and 25 m deep), observation wells (at 1, 2, 4 and 5 m depth) and suction cup lysimeters in the first 4 dm of the soil. We also installed gypsum blocks, TDR probes, tensiometers to follow moisture contents and water tension; Pt-electrodes to monitor redox potentials and static chambers to measure gas emissions.
We also have sampled fields and monitored processes in rain-fed agricultural fields as well as in plots covered by the natural vegetation for comparison.
Terrestrial materials exported from coastal watersheds influence marine food-webs and carbon budgets across the globe, yet much is unknown about the fundamental processes of land-sea carbon cycling or system response to climate change. On an outer-coast island near the center of the Pacific Coastal Temperate Rainforest (PCTR) in North America, the Hakai Institute has developed a long-term coastal margin observatory to examine the flux of terrestrial materials from land to sea – the origins, pathways, processes and food web consequences – in the context of long-term environmental change.
Our study area is Kwakshua Channel and all the land that drains into the channel (approximately 7000 hectares) - a natural laboratory well suited to the study of terrestrial-marine coupling in the hypermaritime coast of western North America. The terrestrial environment is ecologically and physically diverse, varying from bogs and forested wetlands to productive riparian forests. Streams are characterized by high levels of terrestrial organic matter, with concentrations varying across time and space. Kwakshua channel itself is a well-defined and accessible marine waterbody in which to observe physical mixing, microbial processing, food web uptake and ecological interactions.
Beginning in 2013, we established an integrated and multi-disciplinary study across the land-sea gradient. We are using LiDAR and other remote sensing data to examine landscape controls on terrestrial ecosystems and watershed exports. Focusing in on the sources of dissolved organic matter on land, we established a network of terrestrial ecosystem plots across a landscape gradient. Plots are used to examine community composition, stand dynamics, and soil processes, with a subset of plots outfitted for remote monitoring of soil dynamics with sensors. At stream outlets, we use a year-round sampling program and sensor network to quantify, at high temporal resolution, the amount and character of terrestrial exports from seven focal watersheds. Nearshore oceanographic conditions and plankton communities are also monitored year round, adjacent to stream outlets and at other nearshore stations within and outside the channel. Similarly, we conduct year-round sampling of microbial communities - including bacteria and protists - across the terrestrial, freshwater and marine sites.
The Critical Zone - from bedrock to tree-top - indeed plays a critical role in controlling the export of organic materials from coastal watersheds. Consequently, we use the framework of a critical zone observatory to study the watersheds of Calvert Island.
For more information, please visit our webpage.
The Caribou-Poker Creeks Research Watershed (CPCRW) is a 104 km2 basin near Chatanika, Alaska reserved for ecological, hydrological, and climatic research. It is owned jointly by the State of Alaska and the University of Alaska Fairbanks.
LTER — Bonanza Creek
Successional processes associated with wildfire and floodplains; facilitative and competitive interactions among plant species throughout succession; plant-mediated changes in resource and energy availability for decomposers; herbivorous control of plant species composition; hydrologic regime and stream ecology.
The Bonanza Creek Long Term Ecological Research program is located in the boreal forest of interior Alaska, USA. Our facilities are centered in the city of Fairbanks. Research at our LTER site focuses on improving our understanding of the long-term consequences of changing climate and disturbance regimes in the Alaskan boreal forest. Our overall objective is to document the major controls over forest dynamics, biogeochemistry, and disturbance and their interactions in the face of a changing climate. The site was established in Fairbanks, Alaska in 1987 as part of the National Science Foundation's Long-Term Ecological Research (LTER) Program Read More
The BNZ LTER program was established to study patterns and mechanisms of boreal forest succession following fluvial and fire disturbance, and for the first few decades, our monitoring program, long-term experiments and process studies focused on state factor and interactive controls over succession, trophic dynamics and ecosystem function of floodplain and upland chronosequences.
NEON — Caribou Creek - Poker Flats Watershed
Located 30 miles northeast of Fairbanks, this site is within the-managed Experimental Research Forest. The site is located within rolling boreal forest. There is no field housing provided at this site; all work is conducted via day trips from Fairbanks. Mosquitoes are abundant between June and early August and constitute the main challenge to working at Caribou Creek. Weather can also be unpredictable; precipitation in the form of rain or snow can occur any time of year, and average summer temperatures can vary from the 30s to mid-70s.
NEON Data (Core Terrestrial) from this site.