麻豆app

Wil Wollheim (left, conducting research here in a wetter year with former postdoctoral researcher Richard Carey) wants to measure nutrients that flow from beaver ponds.

Bill McDowell wants to know how humans and climate change will affect the water quality of streams in southeastern New Hampshire. But as those streams become trickles or disappear altogether in the face of this summer鈥檚 drought, much of his fieldwork has come up dry.

鈥淭he drought is limiting our ability to sample streams 鈥� some have dried up completely 鈥� and the very low flow makes some experimental work impossible,鈥� says , Presidential Chair and professor of environmental science.

While most of us in the Northeast are feeling the effects of this hot, dry summer 鈥� from the seemingly endless stretch of sunny warmth to the watering bans that shrivel our gardens and crisp our lawns鈥� some researchers at UNH have found the record drought has changed the way they can conduct research.

McDowell鈥檚 research group is studying streams that feed into southeastern New Hampshire鈥檚 Lamprey River.

鈥淲e have sensors in these streams to monitor the chemical and physical parameters and flow has gotten so low in them that we have had to either pull the sensors or just had to do without data for blocks of time,鈥� says Jody Potter, lab manager of the McDowell leads.

Some streams for another project 鈥� a collaboration with the conservation group to restore trout habitat in streams by adding trees and logs 鈥� have also dried up. McDowell鈥檚 team has added the wood in anticipation of future flows, but monitoring for changing nutrient dynamics, the bulk of the UNH work, has been put on hold.

Associate professor , an aquatic ecosystem ecologist who like McDowell is in the department of natural resources and the environment and studies nearby freshwater, has similarly found some sampling sites dry. For one study, his hopes to measure the nutrients and sediments that flow into and out of beaver ponds.

Thirsty Forest

As New England鈥檚 climate changes, 鈥渆ven though we鈥檙e expected to have more total rainfall, we鈥檙e also expected to have more prolonged periods of drought,鈥� says Asbjornsen.

鈥淭he dry weather this summer has certainly amplified the drought we are aiming to simulate,鈥� says McIntire. Initial measurements in this first year of the study have shown that trees are responding to less water by adjusting their stomata, the pores through which moisture leaves a tree, reducing both transpiration 鈥� the evaporation of water from the trees鈥� leaves 鈥� and photosynthesis. 鈥淚 would be willing to bet that this will have a direct effect on tree growth as well, but we don't have that data yet,鈥� McIntire adds.

But this year, those streams are not flowing. 鈥淏ut the beaver pond is still there, so we are monitoring the response of processes in the pond to the drought,鈥� he says. 鈥淗opefully we can compare it with future years that are wetter.鈥�

Other researchers note the value of such comparisons: To a scientist, an unusual year can be a rich source of data, particularly as droughts like this summer鈥檚 are predicted to become more common as our climate changes.

鈥淚t can actually be beneficial to have a year that is really an outlier when we are doing multi-year studies, so that we can听see results that may differ in a dry versus a typical year,鈥� says Extension professor , a crop and sustainable agriculture specialist. On the at the edge of campus, she鈥檚 growing Brussels sprouts and table grapes outdoors as well as tomatoes, peppers and fall-bearing strawberries in high and low tunnels.

The lack of rain has some benefits as well. It鈥檚 made scouting future research sites easier, says Wollheim, because the type of surface 鈥� sand, mud, rock 鈥� on which the stream flows is an important consideration for his work. 鈥淲e can walk along entire stream channels to see what their substrates are,鈥� he says.

On Woodman Farm, Sideman鈥檚 crops have seen far less fungal disease than they do in typical years. 鈥淭his does, however, have a down side,鈥� she says. 鈥淲e often hope to see differences between treatments in susceptibility to diseases, and those differences aren鈥檛 visible in a dry year like this one.鈥�

听

These projects received funding from the (McDowell, Wollheim); (McDowell, Wollheim); (McDowell, Sideman, Asbjornsen, Wollheim); (McDowell); and UNH Facilities (Wollheim). Sideman鈥檚 work was also funded by , , , , and .