Regional Assessment of the Virtual Water of Sheep and Goats in Arid Areas

Ke Zhang

doi:10.11648/j.avs.20180604.12

Abstract

The increased consumption of livestock products is likely to put further pressure on the world’s freshwater resources, an agricultural virtual water strategy will alleviate the water resources pressure of livestock husbandry, especially in arid areas. The research on the virtual water requirement of living animals is still blank in China. Most of the researches on the virtual water of animal products in China adopt foreign data and there is some error with the actual situation in China. In this study, the virtual water requirements of sheep and goats (n=80) in North China were evaluated and validated. Factors that affect animals’ virtual water requirements and the water supply for sheep and goat management were analyzed. We found that the virtual water productivity in sheep at five growth stages (40-day-old [D40], 6-month [M6], 12-month-old [M12], 24-month-old [M24], and 36-month-old [M36]) was lower than that in goats. The amount of virtual water requirements was 496.07 m3 from birth to M36 in sheep and was 217.14 m3 in goats. The water consumes were estimated to be 9 019.4 m3 /t in sheep and 4 825.3m3 /t in goats. The virtual water requirement for feed accounted for more than 99% of the total water consumption. Daily water consumption in rams is larger than that in ewes. We found that the crop type and yield, the proportion of high water consumption feed raw material in complete diet pellets, as well as the flock structure are the three major factors influencing virtual water demand in animals. Our results provided strategies to reduce water consumption in animal husbandry industries in arid areas, and further show that the crop import trade strategies can be used to increase the import of high water-consuming crops, instead of the virtual water consumption of the sheep and goat industry output, thereby alleviating the pressure on local water resources.

Highlights

Freshwater is a renewable resource, but the world's total groundwater supplies are declining with population growth, with the most common water losses occurring in Asia and North America [1]
The results showed that the complete diet pellets virtual water content is highest of sheep at 12 months of ages (Figure 3B), the reason is that the complete diet pellets have the highest proportion of cereals. the feed raw material virtual water content and percent is different in the complete diet pellets, which makes the different levels of complete diet pellets virtual water content at difference age group
The average water content was 5 234 m3/t. These results showed that the virtual water content of goats was 4 825.3 m3 / t, which was lower than the global average [13], but the low degree of modernization in China's sheep and goat industry adds to water consumption and waste

Summary

Introduction

Freshwater is a renewable resource, but the world's total groundwater supplies are declining with population growth, with the most common water losses occurring in Asia and North America [1]. The concept of virtual water was first proposed in 1993 by Professor Allan of King's College London, which led to the field of virtual water research [3, 4]. Research on virtual water has focused on agricultural and livestock products. These products consume large amounts of water in processing primary raw materials. In China, previous study investigated the virtual water flows in the international trade of agricultural products, the result found that the trend that China exported virtual water per year was on the decline while the imported was on a rising trend. From a strategic point of view, there is a lack of evidence for the actual needs and arguments on the maturity of China's regional virtual water trade conditions

Methods

Results

Discussion

Conclusion