A networking resource devoted to biological soil crusts and the researchers who study them. We will provide a means for international scientists to communicate, share their research, share important news and announcements, ask questions and find collaborators. We will also provide a space for informal writing on research, opinion, and ideas (now seeking posters!).

Friday, September 20, 2013

Biocrusts of Northern Arizona NAtional Monuments Post 4: Wupatki


This is the latest in a series, see here for a lichen key, here for a moss key, and here for a description of Walnut Canyon biocrusts.



Wupatki-Wupatki was the largest national monument examined. We found that in the case of potential biocrust abundance low to medium values were observed within the monument. All of our outputs suggest that the areas where biocrusts attain the greatest importance are the limestone flats above the Doney cliffs, including Antelope Prairie. This conclusion is deceptive because it does not take into account eolian reworked cinders. Surfaces covered by cinders are not available habitat for BSCs. We had no available spatial data on the extent of cinder deposits, therefore we generated a map of cinder cover based upon interpolation of our surface data (Figure 1). Amos et al. (1981) provide data on thicker cinder deposits, but do not address the thin eolian deposition of cinders that strongly influences western Wupatki. Because mapping cinder cover was outside the scope of our project, this data should be considered a rough approximation only. The cinder map reveals that a large proportion of Wupatki that otherwise could support BSCs likely does not because a large proportion of the available surface is covered with cinders (Figure 2a). There may however be less cinder deposition on the northern portions of the Doney Cliffs where our models predict high potential for BSC abundance, function and biodiversity.

Figure 1. Surface cinder cover in Wupatki National Monument, estimated by interpolation from non-systematic ground-based samples.

 
Overall, BSC cover is sparse in Wupatki, apparently due to several factors. The cinder deposits of the western portions virtually prohibit biocrust development because there is simply no soil at the surface, i.e. no available habitat. To the east, the Wupatki basin has less cinder deposition but is quite arid and hot, and is lacking in sandy soils which tend to support higher biocrust cover on the Colorado Plateau. This area consists mainly of highly eroded exposures of moenkopi shale, and alluvial terraces of various ages. Minor biocrust development was detected on some alluvial terraces, but was not clearly related to terrace age. Occasionally northern exposures (especially shrub mounds within such sites) supported some crust cover (Figure 2). It is possible, especially in the Wupatki Basin, that the landscape is not at its potential due to the legacy of disturbance both from livestock and the widespread prehistoric agriculture that occurred there. Calcareous sandy soils and non-bentonitic shale-derived soils in low disturbance conditions generally support greater biocrust cover than that observed in the Wupatki Basin.

Figure 2. Soil surfaces in Wupatki National Monument. a. A thin veneer of cinder deposition prohibits biocrust development due to little available habitat at the soil surface. b. A biocrust growing on the north side of a shrub mound on an alluvial terrace.


Thursday, September 12, 2013

Biocrusts of Northern Arizona National Monuments Post 3: Walnut Canyon



This is my third post on the theme of biocrusts in the National Monuments of Northern Arizona. Find a lichen key here, and a moss key here. Walnut Canyon, Wupatki, Sunset Crater, Montezuma Castle (& Well), and Tuzigoot were sampled.

Walnut Canyon- Of the National Monuments sampled above the Mogollon rim, Walnut Canyon is where BSCs are most consistently important.
We sampled intermediate precipitation portions of the Walnut Canyon rim that had been fenced since at least 1974. We also used surrogate sites with Kaibab limestone parent materials in range exclosures near Flagstaff, and on the south rim of the Grand Canyon to capture more variance in climate parameters. In general, we found that the entire canyon rim likely has potential for BSC cover . Even in sites known to have burned relatively recently, we were able to find some BSC development.
            We made the simplifying assumption that the canyon bottom was unavailable to BSCs due to flooding, and that the canyon walls were too steep to afford more than minimal available habitat. North facing slopes supporting Douglas fir stands were examined and found to contain very little BSC habitat. We did observe the mosses S. ruralis and Brachythecium sp., growing along with the lichen Cladonia fimbriata primarily growing in rock crevices and on organic matter. Because of the steep rocky terrain, very low available BSC habitat, and the low spatial extent of these habitats, we chose not to formally survey them.

The entire Walnut Canyon Rim has potential to support BSCs, regardless of the vegetation type. a)  A cyanobacterial-lichen BSC amidst ponderosa pine litter in a  ponderosa pine habitat (inset). b) A cyanobacterial-lichen BSC between Bouteloua gracilis, and surface rocks in an open grassy pinyon-juniper savannah (inset)

Sunday, September 1, 2013

Biocrusts of Northern Arizona National Monuments, Post 2: Moss key

This is my second post on biocrusts of National Monuments of Northern Arizona. See yesterdays post for a lichen key, here's a moss key. Liverworts were not observed by surveyors, but they are likely out there. The keys apply to Wupatki, Walnut Canyon, Sunset Crater, Montezuma Castle (& Well), and Tuzigoot National Monuments.


Field-based key to common biocrust mosses of National Monuments of the southern Colorado Plateau and Colorado Plateau-Sonoran Desert ecotone
1a) Upper leaves or entire plant white or silvery due to lack of chlorophyll; plants usually small (0.5 mm tall)................Bryum argenteum complex (may include B. argenteum, B. lanatum)
1b) Plants not whitish or silvery; plant sizes various............. 2
2a) Plants light green to yellowish, stems up to several cm long, frequently branched with a creeping growth form ……Brachythecium spp.
2b) Plants various colors, stems usually less than 1 cm, not branched or only sparingly branched and.….3
                        3a) Plants lacks awns (hair points on leaf tips), light green to black...4
4a) Plant light green, large (>1mm common) tongue shaped leaves (may be contorted when dry) with mucro at apex, Almost always bearing straight, erect sporophytes (~1-2.5 cm tall); older sporophytes exhibit cylindrical capsules topped with a characteristic white column ....................................Tortula inermis          
4b) Plant forest green above and reddish brown below when dry, shorter plants with linear-lanceolate leaves (sometimes contorted, sometimes ~ imbricate); if present mature sporophytes red with inclined capsule .............................................Ceratodon purpureus
                        3b) Plants with awns (usually whitish and toothed); colors various..5
5a) White awns longer than plant height; often giving appearance of white fuzzy tuft because plant is buried or inconspicuous ............Pterygoneurum spp. (Almost always P. ovatum but can’t be keyed in field without sporophyte)**
5b)White or yellowish awn length less than plant height; plants are generally above ground and easy to see .....6
6a) Awn is a yellowish extension of an acuminate leaf tip, wider at base; plant yellowish green or golden, mostly < 1mm tall .......................7
7a) Plant yellowish green, rarely in dense cushions; arid regions....Bryum kunzei 
7b) Plant golden yellow with a magenta colored stem (view wet), frequently in dense cushions; prefers shrub canopies in higher elevation areas.....Bryum caespiticium
6b) Awn is white and ~ same width along its entire length, plants light green, or darker (not yellow).....8
8a) Plants tall, often > 3mm height; plants lime green-dark green at top, reddish at base; leaves slightly twisted around stem when dry squarrose-recurved (curling back > 90º back from stem) when wet, costa frequently red …………...Syntrichia ruralis
8b) Plants small-med, usually less than 3mm tall: plants dark green-blackish at top, brown at base; leaves not twisted around stem when dry, patent (not curling back > 90º), costa never red…....Syntrichia caninervis

** If sporophyte is present:
5aa) Due to a short seta, the sporophyte capsule is immersed in leaves or barely sticking out, calyptra splits in 2 or more places, plants about 1mm high and green......Pterygoneurum subsessile
5bb) Seta a few mm long, sporophyte capsule exerted, calyptra splits along a single seam, plants very small and awns are much more more visible...............................Pterygoneurum ovatum

Saturday, August 31, 2013

Biocrusts of Northern Arizona National Monuments, Post 1

Preface: I was looking through some old files the other day, and ran across a report I had written on an old research project. The goal of the research was to model the potential abundance of biocrusts in Wupatki, Sunset Crater, Walnut Canyon, Montezuma's Castle (and Well), and Tuzigoot National Monuments in Northern Arizona. The first three are near Flagstaff on the Southern Colorado Plateau. The others are in the Verde River watershed which has more Sonoran Desert vegetation elements.

I never published this, because frankly, the models just were not very exciting. I completely forgot that as peripheral matter, I created species lists, keys, and verbal descriptions and photos of the biocrusts in these National Monuments. It seems a shame for them to just be in a report which only a few people have, so I have decided to share them here in a series of posts. Here's a key to biocrust lichens in the area. (Please note that the Sedona area was not part of sampling and that many more biocrust species would be found there).

Field-based key to common Biocrust lichens of National Monuments in the southern Colorado Plateau and Colorado Plateau-Sonoran Desert ecotone

1a) Thallus crustose, subfoliose, foliose, fruticose or gelatinous...................2

2a) Thallus erect-fruticose, tan to olive green, with white dots (pseudocyphellae) ……………………………………………………………………….Aspicilia hispida
2b) Thallus crustose, subfoliose, foliose or gelatinous, various colors ………..…….3

3a) Thallus foliose, large (usually > 5cm dia.), gray to grayish brown or brown, with felt-like texture on upper surface, commonly with large red apothecia at margins ………………………………………………....Peltigera rufesence
3b) Thallus crustose or gelatinous ………………………………………..….…4

4a) Thallus some shade of yellow or orange ..................................5

5a) Thallus crustose with distinctly lobate margins; lemon yellow usually with some white showing underneath (rarely all white); often with 1mm dia. rust colored apothecia ………....................................Fulgensia desertorum
5b) Thallus inconspicuous, but densely covered with orange apothecia ………….Caloplaca jungermanii

4b) Thallus colored otherwise ........................................................6

6a) Thallus crustose, white to beige, usually with dark gray to black apothecia ………….……Diploschistes muscorum
6b) Thallus gelatinous; usually black but occasionally dark green or brownish, apothecia often lacking ........................7       

7a) Thallus clearly standing up from substrate, thallus margins appear fringed due to finger-shaped isidia ………………………………..Leptogium sp.
7b) Usually very well covered in isidia (look like black balls); colony often forms a small hemispherical mound; if not isidiate, may be somewhat erect (standing up from substrate) ..............................................Collema coccophorum
7c) May or may not be isidiate, lobes of thallus margins usually visible and somewhat swollen; colony tends to form a flat, adnate rosette; marginal thallus lobes may curl up slightly but are generally adnate to soil .....................................Collema tenax

1b) Thallus squamulose ....................................................................................................8

8a) Thallus consisting of gray-green basal squamules, and sometimes erect columns (podetia), found at middle to upper elevations ………………….….....9

9a) Podetia narrow and trumpet shaped …………...….Cladonia fimbriata
9b) Podetia lack cup at top, finger shaped, may have brown apothecia near top of podetia ……. ………………………………….….Cladonia cariosa

8b) Squamules not gray-green, podetia always lacking, various
elevations…………………………………………………………………...…..10

10a) Squamules some shade of brown, tan, or drab olive green ………..11

11a) Squamules drab olive, tan, or chocolate brown, mostly ~1mm dia.; if present fruiting bodies are apothecia .................................12

12a) Squamules olive or tan, if present apothecia are red  …………………………………………………………....13

13a) Flat squamules, mostly round or oval; often dimpled with a slightly darker rim; red apothecia uncommon in the center of the squamule …….................................................Peltula patellata
13b) Undulating small to large squamules (0.5 - > 1 cm), often with lobate margins; large red apothecia (sometimes more than one) usually found in center of squamule ………….Heppia conchiloba

12b) Convex, crowded squamules, chocolate brown, rim not differently colored, black hemispherical apothecia very common ……………………………….….Psora globifera

11b) Squamules mostly > 1mm, cream to light brown to almost black;
perithecia or apothecia may be present (but are not red)......................13

13a) Squamules white-rimmed, convex dark apothecia (~ 1mm dia.) on squamules often observed ................................................14

14a) Squamules chocolate brown, regular and imbricate like ascending shingles ………………...Psora himalayana
14b) Squamules light to chocolate brown, less regular….. ………………………………………...Psora tuckermannii

13b) Squamules not white-rimmed (some taxa may have some sparse pruina around edges though), if present ascocarps are perithecia .......................................................................................15

15a) Squamules solitary or sparsely scattered with an irregular
 margin; Several perithecia always evident as upraised black
 dots with a hole in the middle ...............Endocarpon pusillum
15b) Squamules usually several, sometimes crowded or overlapping, margins regular to lobate; if present, perithecia are difficult to see without a hand lens .............Placidium spp.

10b) Squamules not brown; Apothecia may be present...............................16

16a) Squamules pink to brick red with a white margin; apothecia
marginal and convex ......................................................Psora decipiens
16b) Squamules not pink or red, pruinose on most of upper surface ..17

17a) Squamules light green, entire or lobate, tan apotecia with white rim usually present (most common on rocks but occasionally on soil)…………………………………………..Lecanora muralis
17b) Squamules not as above …………………………………...18

18a) Small squamules (< 2 mm) green to gray with blue-gray pruina, strongly convex without white margins; apothecia black, borne between squamules …........Toninia sedifolia
18b) Large squamules (>2mm), white due to dense pruina……………………………....19

19a) Large squamules, not strongly lobate with downturned margins, small hemispherical apothecia green to black, born between squamules, forming hemispherical brain-like colonies; especially common on calcareous soils ............Psora cerebriformis
19b) Very large squamules (up to 2 cm), not lobate with conspicuous depression in center on squamule, small balck apothecia borne on rim of squamule ……………………………………….Psora crenata