Challenges for Sustainable Use of the Fish Resources from Lake Balkhash, a Fragile Lake in an Arid Ecosystem

Waterbird guilds predict environmental attributes of inland saline aquatic ecosystems on multi-spatial scales

Inland saline waters in Central Asia constitute an important part of steppe ecosystems, providing considerable ecological functions and ecosystem services. Here we aim to present a multi-spatial scale analysis of nutrient cycling and transport waterbird guilds, and the environmental attributes of saline-soda aquatic ecosystems in Kazakhstan. The density, biomass, and diversity of waterbird guilds was determined in the case of three nutrient cycling and transport guilds: a) net-importer (IM), b) importer-exporter (IMEX), c) net-exporter (EX), according to the Boros's guild classification method, and for several traditional feeding guilds: carnivorous, herbivorous, invertebrate eater, omnivorous and piscivorous. Our results revealed that waterbird guilds, as predictors represented by the complete waterbird community, are in close relationship with several (N = 12) environmental attributes of inland saline waters through complex trophic linkages of waterbird populations on multi-spatial scales. The density and the biomass of the EX and IMEX guilds are strongly and positively correlated (i) with the productivity metrics of habitats (e.g., CHL, GPP), indicating their trophic position, and (ii) with water depth. We found significant correlations among guild density, biomass, diversity and environmental attributes on multi-spatial scales for IMEX and EX. Our results revealed that IMEX predicts the surrounding environment of aquatic habitats, whereas EX species are substantial environmental predictors of aquatic ecosystems. However, the diversity metric had valid models only with EX. The herbivorous and omnivorous guilds, that feed chiefly on plant materials consist mainly of IMEX and EX duck species, which were positively related to grassland coverage and the shoreline development index. As a methodological result, here we present a novel approach, the guild transport index, which has more robust relationships with environmental attributes than individual guilds, thus it provides a complex evaluation of the nutrient cycling by birds between aquatic and terrestrial environments on multi-spatial scales.

The Changing Dynamics of Kazakhstan’s Fisheries Sector: From the Early Soviet Era to the Twenty-First Century

Kazakhstan, a former Soviet republic that is now independent, lies near the center of arid Eurasia. Its sparse hydrographic network includes a small number of large rivers, lakes, and reservoirs, many ponds and smaller streams, as well as littoral zones bordering the Caspian Sea and the Aral Sea. A diverse fisheries sector, initially based on wild fish capture and later including aquaculture, developed in these waters during the Soviet era, when animal agriculture was unable to meet the protein needs of Soviet citizens. The sector, which was originally centered on the Volga–Caspian basin, was tightly managed by Moscow and benefitted from coordinated investments in research, infrastructure, and human resources, as well as policies to increase the consumption of fish products. Independence in 1991 administered a political and economic shock that disrupted these relationships. Kazakhstan’s wild fish harvests plummeted by more than two-thirds, and aquaculture collapsed to just 3% of its previous level. Per capita consumption of fish products also declined, as did processing capacity. Favorable recent policies to define fishing rights, incentivize investments, prevent illegal fishing, and make stocking more effective have helped to reverse these trends and stabilize the sector. Continued recovery will require additional steps to manage water resources sustainably, prioritize the use of water for fish habitats, and minimize the effects of climate change. This comprehensive assessment of Kazakhstan’s fisheries sector over the past century provides the basis to understand how long-term dynamic interactions of the environment with the political economy influence fisheries in Eurasia’s largest country.

Evolution of landscape pattern and the association with ecosystem services in the Ili-Balkhash Basin

The Ili-Balkhash Basin in Central Asia is an arid endorheic basin shared by China and Kazakhstan. Population growth, socio-economic development, ecological conservation measures, and climate change have spurred land use and land cover changes and ecosystem services variations. This study used the long-term dataset from 1992 to 2018 to detect the landscape pattern evolution and its association with ecosystem services. The landscape pattern was quantified using landscape metrics, and the GeoDetector model quantified the driving factors of landscape pattern evolution. The ecosystem service value was assessed using the benefit transfer method. The time series trend was identified by the linear regression analysis combined with the Mann-Kendall algorithm, and Pearson's correlation coefficient was used to confirm the correlation. The temporal dynamics of the landscape pattern indicated the significant conversion of bare land to grassland. Cropland and urban land expanded significantly at the expense of forestland, grassland, and bare land. Various landscape elements tended to be more uniformly distributed across the basin with more regular shape and higher aggregation. The ecosystem service value increased significantly, and its correlation with the landscape pattern varied according to land use and land cover (LULC) types. The weakened shape complexity, the strengthened aggregation degree, and the more uniform distribution of different LULC types helped elevate total ecosystem service value. The results advanced the understanding of landscape pattern evolution and provided the scientific reference for land management regarding ecosystem services. Given the watershed ecosystem's integrity, transboundary cooperation between China and Kazakhstan was suggested to reinforce watershed sustainability through integrated watershed land resource planning and the joint adaptive strategies to climate change.

Quality of Drinking Water in the Balkhash District of Kazakhstan’s Almaty Region

The thinly populated Balkhash District of Kazakhstan’s Almaty Region lies in the lower reaches of the Ili-Balkhash basin, which is shared by China and Kazakhstan. The district is arid and heavily dependent on inflows of surface water, which are threatened by the effects of upstream population growth, economic development, and climate change. The quality of drinking water from centralized water systems and tube wells in nine villages of the district was analyzed, and the organoleptic properties of water from these sources was also assessed by an expert and via surveys of local residents. Although most samples met governmental standards for the absence of chemical impurities, high concentrations of mineralization, chlorides, boron, iron, and/or uranium were present in some well water samples. Levels of these pollutants were as much as 4-fold higher than governmental maxima and as much as 16-fold higher than concentrations reported previously in surface water. All centralized water samples met standards for absence of microbial contamination, but total microbial counts in some well water samples exceeded standards. Organoleptic standards were met by all the water from five villages, but centralized water from one village and well water from four villages failed to meet standards based on expert judgment. Residents were, for the most part, more satisfied with centralized rather than well water, but there was no obvious relationship between the failure of water to meet standards and the locations or populations of the settlements. This is the first comprehensive assessment of groundwater used for drinking in the lower Ili-Balkhash basin, and although it relies on a limited number of samples, it nevertheless provides evidence of potentially serious groundwater contamination in the Balkhash District. It is thus imperative that additional and more detailed studies be undertaken.