Illinois Natural History Survey - University of Illinois

Biotic Inventory of Kyrgyz Grasslands

Temperate grasslands are the most threatened of the world's ecosystems. In Illinois less than 0.1% percent of our original native prairie vegetation remains and most of the loss has occurred within the last 150 years. Native grasslands harbor an enormous diversity of species, including the most important food plants of humans and domestic animals. Consequently, they also harbor the herbivorous insects that consume these plants, some of which are now considered agricultural pests, as well as the natural enemies of these pests. Thus, study of native grassland biotas is desirable not only because they are rapidly disappearing worldwide, but also because of the economic importance of grassland organisms.

Despite the importance of grasslands to human civilization, basic knowledge of the grassland biota is still very incomplete. New species, particularly of diverse groups such as insects, continue to be discovered, and the interactions among grassland plants and animals, such as the relationship between plants and their insect pollinators, remain poorly understood. The relationships among the floras and faunas of different grassland regions are also incompletely known. Such knowledge is crucial to an improved understanding of the factors that create and maintain native grasslands as functioning ecosystems. Globalization of the economy and the increasing impacts of non-native species provide additional impetus for the study of grassland biotas. Many North American grasslands are dominated by plant and animal species introduced from Eurasian grasslands, and accidental introductions of exotic species are becoming more frequent.

Although intensive study of the remaining Illinois prairies continues to be a top priority at the Illinois Natural History Survey, studies of grasslands in other parts of the world are also necessary to provide baseline data on poorly sampled regions and to help place the Illinois biota in a global perspective. Central Asia has some of the world's most extensive remaining temperate grasslands, most of which are encompassed within the borders of the former Soviet Union. The breakup of the Soviet Union has facilitated closer collaboration between U.S. and former Soviet scientists and provided opportunities for fieldwork in regions formerly off limits to U.S. researchers. Entomologists and botanists from INHS took advantage of this to conduct an inventory of the grassland vascular plants and arthropods of a former Soviet Republic, Kyrgyzstan, during the 1998-2000 field seasons.

Kyrgyzstan is a country about the size and latitude of South Dakota, situated to the northwest of China and bordering the other former Soviet central Asian republics of Tajikistan, Uzbekistan, and Kazakhstan. The main physiographic features of Kyrgyzstan are the Tien Shan, a mountain range consisting of a series of east-west trending ridges including numerous peaks over 5000 m tall, and Issyk-Kul, a large freshwater lake in the northeastern part of the country. Kyrgyzstan is an attractive place to study grasslands because it has a wide variety of grassland types arranged along relatively steep elevational and moisture gradients. Forests in Kyrgyzstan are almost entirely restricted to riverbanks and to the ridges surrounding Lake Issyk-Kul.

The goals of our project were: (1) to document the vascular flora and arthropod fauna of Kyrgyz grasslands, (2) to collect specimens of as many species as possible for use in basic systematic research, (3) to obtain quantitative data on arthropod and plant species richness and vegetative cover, (4) to document ecological interactions among arthropods and plants; and (5) to create a specimen-level relational database for the specimens collected.

Our sampling plan involved visiting as many sites as possible that represented a variety of grassland types and elevational classes during three month-long expeditions conducted over three years (1998-2000). Some sites were sampled repeatedly over the three years and some were visited only once. At 42 sites, we established 100-m transects for quantitative sampling of both plants and insects. Within these transects we sampled plants in 20 3/4-m² quadrats, recording species occurrence and percent cover. We sampled insects along these same transects using a sweep net and by vacuuming. We also made many additional collections of plants and insects by walking each site in an attempt to document the flora and fauna as thoroughly as possible.

Over the three years of the project, we sampled 119 sites and collected 579 insect samples containing approximately 100,000 individual insect specimens. We also collected about 2,300 plant specimens. The processing of these samples and identification of species have been the most time-consuming part of this work. We are currently distributing plant and insect specimens to specialists for identification and constructing a relational database that will include a record for each specimen collected linked to information on the locality. Eventually, we plan to incorporate our data and specimens into a variety of analyses. These analyses will include the estimation of species richness, diversity, and complimentarity; cladistic biogeographic study of Holarctic grasslands; study of community structure and its determinants using ordination; and basic systematic research including phylogenetic analysis and the description of new genera and species.

Chris Dietrich, Center for Biodiversity

Charlie Warwick, editor